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engine plans #3279769
01/01/25 05:43 PM
01/01/25 05:43 PM
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Michigan
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cha1lenger Offline OP
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I have experience racing big block and small block mopar, but my next endeavor is exploring the Gen 3 hemi. I have nearly no experience with this platform. I love that the BGE block is so strong, to get a race block for B/RB or SB is soooo cost prohibitive.

My goals:
650+ horsepower naturally aspirated and bulletproof reliability for bracket racing
7000 RPM, maybe 7500 max? I don't want to make valvetrain a reliability concern

Tentatively figuring on BGE block, 426 stroker kit, AFR heads?, drag pak intake.

I am unsure on the heads, if an aftermarket head is money well spent. I am unsure on the valvetrain, I can't believe what Jesel or T&D ask for rocker arms. I am also tentatively leaning toward carburetor but could be swayed either way. Also, not sure if someone has experience with a cam choice for this target.

Essentially, I am looking for advice on what pieces it will take to get to my goals. I don't want to cheap out, but like anybody I want to maximize bang for the buck.

Last edited by cha1lenger; 01/01/25 05:49 PM.
Re: engine plans [Re: cha1lenger] #3279826
01/01/25 08:51 PM
01/01/25 08:51 PM
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Kalispell Mt.
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HotRodDave Offline
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Originally Posted by cha1lenger
I have experience racing big block and small block mopar, but my next endeavor is exploring the Gen 3 hemi. I have nearly no experience with this platform. I love that the BGE block is so strong, to get a race block for B/RB or SB is soooo cost prohibitive.

My goals:
650+ horsepower naturally aspirated and bulletproof reliability for bracket racing
7000 RPM, maybe 7500 max? I don't want to make valvetrain a reliability concern

Tentatively figuring on BGE block, 426 stroker kit, AFR heads?, drag pak intake.

I am unsure on the heads, if an aftermarket head is money well spent. I am unsure on the valvetrain, I can't believe what Jesel or T&D ask for rocker arms. I am also tentatively leaning toward carburetor but could be swayed either way. Also, not sure if someone has experience with a cam choice for this target.

Essentially, I am looking for advice on what pieces it will take to get to my goals. I don't want to cheap out, but like anybody I want to maximize bang for the buck.



At only 650 HP you don't even need to port the 6.4 heads, they flow similar to a fully ported W2 SB head. A fully ported 6.4 or BGE head can work to 800hp probably more in the right hands. Aftermarket heads are a huge waste of money on a 650HP 426. I would stick to the 426CID because the longer stroke requires such a short piston, keeping some amount of piston height is good for longevity. The stock rockers and even the factory hydraulic lifters are fine at 7000 or even 7500RPM. I wouldn't consider any other intake for carb or EFI if I could make room for a drag pack. Buying a BGE long block from a JY is like buying a R3 block, Indy 360 heads, good ductile iron non adjustable W2 rockers and a crank you can sell for $600, a $200 cam, a set of pistons you can get a couple hundred out of and if it has an intake you can make another $400 on it.


I am not causing global warming, I am just trying to hold off a impending Ice Age!



Re: engine plans [Re: HotRodDave] #3279931
01/02/25 11:31 AM
01/02/25 11:31 AM
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cha1lenger Offline OP
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Originally Posted by HotRodDave
At only 650 HP you don't even need to port the 6.4 heads, they flow similar to a fully ported W2 SB head. A fully ported 6.4 or BGE head can work to 800hp probably more in the right hands. Aftermarket heads are a huge waste of money on a 650HP 426. I would stick to the 426CID because the longer stroke requires such a short piston, keeping some amount of piston height is good for longevity. The stock rockers and even the factory hydraulic lifters are fine at 7000 or even 7500RPM. I wouldn't consider any other intake for carb or EFI if I could make room for a drag pack. Buying a BGE long block from a JY is like buying a R3 block, Indy 360 heads, good ductile iron non adjustable W2 rockers and a crank you can sell for $600, a $200 cam, a set of pistons you can get a couple hundred out of and if it has an intake you can make another $400 on it.


Thanks for the reply!!

Follow up question, what would it take N/A to get more horsepower? 650 was just a number I pulled from nowhere. I agree with you I don't want to stroke past 426 even though it would be tempting.

And 6.4 in junkyard seems like nearly impossible to find for under $5k. Considering I wouldn't use the rotating assembly, it seems like the math makes sense to buy a new block and start from scratch. And I was looking at porting stock heads, by the time you buy them and send them for porting it seems to start adding up fast in cost. I certainly hadn't considered what it would 'earn' to sell off the pieces that aren't re-used.

Re: engine plans [Re: cha1lenger] #3279942
01/02/25 11:52 AM
01/02/25 11:52 AM
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RTSE4ME Offline
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Finding a JY engine is the way to go unless you have all the small parts laying around.
Once you get passed around 650 HP on a n/a GEN3 prices get stupid better off with boost. I think there some decent turbo headers available now at reasonable prices.
I bought complete jJY BGE engine last year for under a grand too bad it hurt the block.

Re: engine plans [Re: cha1lenger] #3279953
01/02/25 12:33 PM
01/02/25 12:33 PM
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Tulsa OK
Bad340fish Offline
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Originally Posted by cha1lenger
Originally Posted by HotRodDave
At only 650 HP you don't even need to port the 6.4 heads, they flow similar to a fully ported W2 SB head. A fully ported 6.4 or BGE head can work to 800hp probably more in the right hands. Aftermarket heads are a huge waste of money on a 650HP 426. I would stick to the 426CID because the longer stroke requires such a short piston, keeping some amount of piston height is good for longevity. The stock rockers and even the factory hydraulic lifters are fine at 7000 or even 7500RPM. I wouldn't consider any other intake for carb or EFI if I could make room for a drag pack. Buying a BGE long block from a JY is like buying a R3 block, Indy 360 heads, good ductile iron non adjustable W2 rockers and a crank you can sell for $600, a $200 cam, a set of pistons you can get a couple hundred out of and if it has an intake you can make another $400 on it.


Thanks for the reply!!

Follow up question, what would it take N/A to get more horsepower? 650 was just a number I pulled from nowhere. I agree with you I don't want to stroke past 426 even though it would be tempting.

And 6.4 in junkyard seems like nearly impossible to find for under $5k. Considering I wouldn't use the rotating assembly, it seems like the math makes sense to buy a new block and start from scratch. And I was looking at porting stock heads, by the time you buy them and send them for porting it seems to start adding up fast in cost. I certainly hadn't considered what it would 'earn' to sell off the pieces that aren't re-used.


If you happen to find one I am in the market for a good 6.4 crank. I bought a cheap 6.4 off of eBay that I knew might need a crank and it turns out it does. I am in zero rush.

I had the same thoughts as you on building from new but with a junkyard engine you get all those little parts and nuts and bolts that add up really fast when it comes to replacement. I paid a low enough price that if nothing below the heads turns out usable I still did OK just not great.


68 Barracuda Formula S 340
Re: engine plans [Re: RTSE4ME] #3279961
01/02/25 12:48 PM
01/02/25 12:48 PM
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cha1lenger Offline OP
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Originally Posted by RTSE4ME
Finding a JY engine is the way to go unless you have all the small parts laying around.
Once you get passed around 650 HP on a n/a GEN3 prices get stupid better off with boost. I think there some decent turbo headers available now at reasonable prices.
I bought complete jJY BGE engine last year for under a grand too bad it hurt the block.


Can I ask how you found the engine? I am having like zero luck.

Re: engine plans [Re: cha1lenger] #3279994
01/02/25 02:56 PM
01/02/25 02:56 PM
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RTSE4ME Offline
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Facebook MP, it was cheap enough to take a chance. Only reason I bought it like most junk on Facebook.
I sold the cam , exhaust manifolds and other bits off it to get my money back. Still have block,crank & heads.
This was my 4th Gen3 engine I have bought... locked up. First 6.4 though.

Re: engine plans [Re: RTSE4ME] #3280039
01/02/25 06:03 PM
01/02/25 06:03 PM
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Pattison Texas
CSK Offline
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a new BGE block is only 2k


1968 Charger COLD A/C Hilborn EFI
512ci 9.7 compression, Stealth heads, 4.10 gear A518 ODtrans 4100lb,10.93 full street car trim
2020 T/A 392 Stock 11.79 @ 114.5

Re: engine plans [Re: CSK] #3280046
01/02/25 06:24 PM
01/02/25 06:24 PM
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Dart 500 Offline
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A stock SRT 392 will spin over 500 on an engine dyno, so just go from there. If built to RPM you may not need to go all the way to 426 for another 150hp

Re: engine plans [Re: Bad340fish] #3280097
01/02/25 10:34 PM
01/02/25 10:34 PM
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Kalispell Mt.
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HotRodDave Offline
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Originally Posted by Bad340fish
Originally Posted by cha1lenger
Originally Posted by HotRodDave
At only 650 HP you don't even need to port the 6.4 heads, they flow similar to a fully ported W2 SB head. A fully ported 6.4 or BGE head can work to 800hp probably more in the right hands. Aftermarket heads are a huge waste of money on a 650HP 426. I would stick to the 426CID because the longer stroke requires such a short piston, keeping some amount of piston height is good for longevity. The stock rockers and even the factory hydraulic lifters are fine at 7000 or even 7500RPM. I wouldn't consider any other intake for carb or EFI if I could make room for a drag pack. Buying a BGE long block from a JY is like buying a R3 block, Indy 360 heads, good ductile iron non adjustable W2 rockers and a crank you can sell for $600, a $200 cam, a set of pistons you can get a couple hundred out of and if it has an intake you can make another $400 on it.


Thanks for the reply!!

Follow up question, what would it take N/A to get more horsepower? 650 was just a number I pulled from nowhere. I agree with you I don't want to stroke past 426 even though it would be tempting.

And 6.4 in junkyard seems like nearly impossible to find for under $5k. Considering I wouldn't use the rotating assembly, it seems like the math makes sense to buy a new block and start from scratch. And I was looking at porting stock heads, by the time you buy them and send them for porting it seems to start adding up fast in cost. I certainly hadn't considered what it would 'earn' to sell off the pieces that aren't re-used.


If you happen to find one I am in the market for a good 6.4 crank. I bought a cheap 6.4 off of eBay that I knew might need a crank and it turns out it does. I am in zero rush.

I had the same thoughts as you on building from new but with a junkyard engine you get all those little parts and nuts and bolts that add up really fast when it comes to replacement. I paid a low enough price that if nothing below the heads turns out usable I still did OK just not great.



I have one from a 2022 6.4 that was in a fire, I bought in 2023 so almost no miles. I also have another that needs turned down. Where are you located?


I am not causing global warming, I am just trying to hold off a impending Ice Age!



Re: engine plans [Re: HotRodDave] #3280178
01/03/25 11:26 AM
01/03/25 11:26 AM
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Tulsa OK
Bad340fish Offline
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Originally Posted by HotRodDave



I have one from a 2022 6.4 that was in a fire, I bought in 2023 so almost no miles. I also have another that needs turned down. Where are you located?


I am in Tulsa Oklahoma


68 Barracuda Formula S 340
Re: engine plans [Re: Bad340fish] #3280240
01/03/25 02:29 PM
01/03/25 02:29 PM
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With a stroker 6.4, 650 HP should be easy peasy with stock heads and the right cam and compression.

A JY is going to want a premium for any 6.4, but there are deals out there.

I gave $2400 for the following package deal from a guy's abandoned project -

*Stock bore BGE 6.4 complete short block (supposedly 18K miles from a cab fire in a service truck and the block sure looked low mileage)
*Stock BGE complete heads w/rockers
*SRT front cover
*Manley 4.08 crank
*Manley Rods
*Billet main caps
*ATI balancer

The stroker stuff was originally used in a 6.1 block, so I would have had to buy mix/match new rods/pistons and deal with the crank snout/front cover situation AND this 6.4 block was one of the blocks with the "short" cylinders that are difficult to put a stroker crank in.

I sold all of the used stroker stuff for $1600 and that paid for machine work (hone and balance), NEW replacement SRT 6.4 pistons/rods, head work, rod and main bearings, and all new bolts. Polished the OE 6.4 crank (forged) and the short block is done.

$$$$....

$2400 short block and head work
$150 oil pump
$400 ATI balancer
$400 head work
$480 cam
$500 lifters
$180 pushrods
$350 springs/retainers/locks
$350 oil pan and pick up
$650 carb intake (OUCH)
$350 gaskets

Less than $6500 intake to pan, not including the cheesy valve covers. (Stock VC's would work just fine) CR is a measured/calculated 10.93:1. Heads FLOW! Fresh VJ on the BGE heads, showed us 336 cfm @ .600" Then 6 hours ($400) worth of massaging by my cylinder head guy got us 362/248 cfm @ .600"

Will it make 700 HP? No way. 650? Nope, but should be north of 600 on pump gas.

So yea, as HRDave said, I have the equivalent to a 392 small block, R3 Block, ported Indy heads, and Indy intake...LOL Fun fact: On the flow bench that Prefix intake was a ZERO loss when bolted to the head.

hemi.jpg
Last edited by cudadoug; 01/03/25 04:27 PM.
Re: engine plans [Re: cha1lenger] #3280269
01/03/25 04:44 PM
01/03/25 04:44 PM
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Quakertown PA
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Tay Offline
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426ci/650HP , is not hard with a G3 , Hell ,depending on the engine management system , Blueprint crate 426 makes a legit 610hp/520Tq with a crappy rip off job of Holley’s old G3 Sniper intake , 90mm Throttle body ,Stock Apache heads 2.14X8mm 1.645X8mm valves …. Cam they come with is 614/.614 lift ,230/255@ .050 115 LSA cam and 10.40 to 1 compression, on good 93oct and some creative timing, it’ll make as much as 625/540.
We’ve run them with a bench mount Ram1500 2014 PCM, hit 615hp and called it a day. With a Holley Terminator system 620 is not out of the question, just plug and go.
We had one (BluePrint426) on the dyno new year’s day made 650@ 6500, 585 @5600 with a Drag pak Intake , out of the box Holley Ulitmit XP 950 carb and MSD Hemi-6, same engine with Comp Cams 201-337-17 .635/.635 229/241 @ .050 117LSA made 675hp @ 6800 &610Tq @ 5800.
Hughes Engines did 720HP (then re-did the dyno sheet to say 740) back in late 2016 maybe 17 , with a 6.1 based 426 (4.08X4.08) If I remember they claimed Compression was 13.1 to 1 They used the pre Eagle head with 2.10 and 1.625 valves, heads were flowing 330@ 650 lift Intake was a Ritter drag pak copy, carb was a 950 Holley, MSD hemi 6 box, cam was .640/.640 250/255 @/050 110 lsa, Peak HP was 7100-7500. Depending on which copy of the dyno sheet was posted, I’ve seen that “package” done a few times, and 700hp with 12 to 1 is attainable and more along what I’ve done and have seen.
I’ve built that “Hughes combo” 6 times with 6.1 blocks, all ranging between 421 and 428ci, once was 4.055X 4.08 (421CI) with a set of Pre Eagle heads done by Performance Injection out of Delaware, intake manifold started out as a pair of R5P7 Mopar that were cut up, welded ,mangled, re-welded, re-mangled, 950 Holley, compression was 11.8 to 1 ,Cam was Howards 786965-13 .625/.600 237/237 @ .050 113 lsa , made 680ishHP @ 7000 ,620ish Tq at 5800 on 93 oct, at the track in a 71 duster, 3k race weight , ran 9.80s 138-145mph at Atco(RIP Atco) 3 of the other builds were with Eagle heads, 2.125/1.625 valves , same Howards 786965-13 cam, roughly 690/700 ish hp, same TQ results, the other 2 versions of this combo were with MMX ported Apache/BGE heads , one was 4.08X4.08(426) the other was 4.075X 4.05(422) roughly 700ish HP, but both of these made peak Tq above 6k.
I like Eagle heads Vs Apache/BGE heads for the street type builds, the smaller Exhaust valve keeps TQ peak lower and seems to carry the TQ band 500RPMs longer.
AFR and the New BlackBird heads , those are for those who have money to spend on special lifters/ custom cams and 4k+ rocker gear, let’s face it , What good are heads that flow over 400cfm @ 700lift if the biggest practical cam you can buy is .640(+/- .010) the OEM style lifter and cam core limits the G3 to about .660 lift, besides most people don’t spin these G3s high enough to utilize the 375CFM that the average port job on an Apache/BGE yields.
Stock rockers will spin to 8k with some prep work, Lash caps are your HIGH rpm friend MAKE sure the Ends of the rocker are even , no casting high spots , Banana grove the shafts, the top side of the shaft has 2 oling holes, one for “rest” the other for “max Lift” issue is the Max lift hole gets blocked once you go over .550(gross) lift, hence the reason a lot of people complain about burnt tips. The bottom side of the shaft has one hole which is a constant feed. Rocker shafts hold downs like the ones Stanke sells, are a preference thing, I spin my 380CI G3 to mid 7kRPMs with stock oem hold downs,(and stock oil pump) but…I do have rocker shaft collars to keep the rockers from shifting back and forth.
Lifter Trays, AAD performance has a Billet Aluminum one that is worth the $220(as of this posting) , it’s great piece of mind ,nothing says Crap like one of the OEM plastic lifter trays cracking…Granted , it’s rarity for those OEM trays to break but they do.
Best option, find a 392SRT or 6.4l truck engine, either buy a stroker kit, or DIY a kit. Eagle, Manley, Scat, Molnar, K1 all have 4.05 cranks, doesn’t matter which one you buy, they’ll all take a 700HP beating. Rods that’s your choice. DSS pistons are worth looking into, good price, part# 1-6817-4090 is a +4 dome STD bore 1.12 pin height, it’s for a 4.05 crank with 6.125 Rods, with Apache/BGE head this piston is 12.1 to 1, I’m building a 427(4.10X4.05) next week with this piston DSS piston,
One of great things about the G3 is ,you can run as high as 12 to 1 on the street with 93oct. with aftermarket pistons.
Next best deal is a OEM 392, there are a lot of builds out there with “drop in forge piston and rods” 600 street able HP” the stock 392 crank is good for 750-800hp and mid 7k rpms , they don’t start to “jump rope” till high 7k.
Intake , For EFI the Edelbrock Victor will get you to 7kRPMs , but that’s about it’s high point, the OEM intakes are good for mid 6kRPMs,
Holley HI-Ram is best all purpose option, Go EFI, use one top, Change over to Carb, go buy a different top, in a carb application, the Dual 4150 top is max effort , and fueling is very even.
All out Carb, the Drag pak is within a few HP of the twin 4150 top HI Ram…for single carb , Drag pak is the best option…. if you don’t mind the Carb sticking through the hood, Ritter single plane has some fueling issues, mostly 5/7 passage, but fixable, it will not out power the Drag pak, Prefix has a good carb Intake , broad Tq ,works well between mid 4k to 7k RPM, I like to think of it as the old B/RB Holley street dominator intake.

Holley Single plane.......For Carb...LOL , it's a Joke it's only value is for those who don't want to cut a hole in their hood.....For EFI , it's actually not bad, More for the Stocker types who want more power above 6k but don't want to buy a Prefix or Drag pak.

The Odd ball intake, Indy Mod man, not bad for EFI, not going to set any track records either, Last but not least in the carb application is OCperformance Dual plane, Think of it as the Performer RPM for the G3.

Last edited by Tay; 01/03/25 04:56 PM.
Re: engine plans [Re: cudadoug] #3280273
01/03/25 04:58 PM
01/03/25 04:58 PM
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Quakertown PA
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Tay Offline
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Originally Posted by cudadoug
With a stroker 6.4, 650 HP should be easy peasy with stock heads and the right cam and compression.

A JY is going to want a premium for any 6.4, but there are deals out there.

I gave $2400 for the following package deal from a guy's abandoned project -

*Stock bore BGE 6.4 complete short block (supposedly 18K miles from a cab fire in a service truck and the block sure looked low mileage)
*Stock BGE complete heads w/rockers
*SRT front cover
*Manley 4.08 crank
*Manley Rods
*Billet main caps
*ATI balancer

The stroker stuff was originally used in a 6.1 block, so I would have had to buy mix/match new rods/pistons and deal with the crank snout/front cover situation AND this 6.4 block was one of the blocks with the "short" cylinders that are difficult to put a stroker crank in.

I sold all of the used stroker stuff for $1600 and that paid for machine work (hone and balance), NEW replacement SRT 6.4 pistons/rods, head work, rod and main bearings, and all new bolts. Polished the OE 6.4 crank (forged) and the short block is done.

$$$$....

$2400 short block and head work
$150 oil pump
$400 ATI balancer
$400 head work
$480 cam
$500 lifters
$180 pushrods
$350 springs/retainers/locks
$350 oil pan and pick up
$650 carb intake (OUCH)
$350 gaskets

Less than $6500 intake to pan, not including the cheesy valve covers. (Stock VC's would work just fine) CR is a measured/calculated 10.93:1. Heads FLOW! Fresh VJ on the BGE heads, showed us 336 cfm @ .600" Then 6 hours ($400) worth of massaging by my cylinder head guy got us 362/248 cfm @ .600"

Will it make 700 HP? No way. 650? Nope, but should be north of 600 on pump gas.

So yea, as HRDave said, I have the equivalent to a 392 small block, R3 Block, ported Indy heads, and Indy intake...LOL Fun fact: On the flow bench that Prefix intake was a ZERO loss when bolted to the head.


Hey I like those cheesy Valve cover.

Prefix's intake was designed for CASCAR, lots of R&D went in to it......it realy is the best all round/multy purpose intake, both EFI and Carb.

Re: engine plans [Re: Tay] #3280293
01/03/25 06:47 PM
01/03/25 06:47 PM
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cudadoug Offline
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[
[/quote]

Hey I like those cheesy Valve cover.

Prefix's intake was designed for CASCAR, lots of R&D went in to it......it realy is the best all round/multy purpose intake, both EFI and Carb. [/quote]

Lol... they are better than the FUGLY OE covers. At $399, a better option (for me) than the $1000-up billet covers, or even the sheet metal versions.

Yes, I learned about that Prefix intake several years ago. Once we had it in our hands and on the flow bench, wow! Plus...I don't have the hood clearance for a DP intake

Re: engine plans [Re: cha1lenger] #3280523
01/04/25 06:51 PM
01/04/25 06:51 PM
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Deland, Florida
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426 with 13.1 comp I'm assuming race fuel is not an isssue if it's a bracket car 6.4 heads with good valve job and the right cam with the rest of the package you have will make 650 pretty easy. Don't cheap out on the oiling system good pan windage tray spend some time detailing that.

Re: engine plans [Re: cha1lenger] #3280649
01/05/25 12:05 PM
01/05/25 12:05 PM
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Trumbauersville PA
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I have a lot to say on this subject, so I'm going to make 3 separate posts.

Heads:
, here is why I say AFR heads are not a bad option, but are not for every one.
If you don't have a set of Apache(BGE) heads to start with , you can find them on eBay between $500 and $1800 , there's at least 1 set every week, Facebook Market place there's always a set depending on where you live , here in Pa/NJ/NY/MD/DE there's 2 to 3 sets a month .(I picked up a set in Nj for $800 yesterday).
So now I have some core heads, I could send them to Katech(one of the better services) for their CNC port job roughly $1200, in return I get 375/230CFM @.650 lift. ,total of $2k plus shipping, now keep in mind they use stock valves and springs on this package, stainless valves and good springs will add another $5-$700 to the cost( New total $2700) I could send these off to MMX get there same results port job for $2300(total $3100), upgraded parts $4100(yeap 4100 , those valves better be titanium for that added cost) Total now is $4900.. you could go to HHP and spend $2200 and get the same flow #s (total$3000) and you do get better than stock springs and valves.

Generally speaking here and I don't care who does the port work, 375CFM is highest CFM you'll get with a 2.14 Intake valve(nothing to sneeze at I know) , 2.18 valve gets a few more, 2.20 with a 6mm stem will go 400CFM @.650 lift.
AFR Black Hawk 224CC , $3600 bare ,$4400 assembled with all the cool parts, No Core charge, no searching for cores you get 385/255CFM @ .650 lift.
The AFR heads have better Cross sectional area to work with, and there is more material under the valve spring pocket, which will support as much as 550lbs open load, OEM head will crack at that load rating.

If the end user is one of those 1 in 20 people who wants the MAX, squeeze every last drop, Cam tunnel, Dry sump/External oil system, 8K+ Rpm build.....the AFR are the best cost effective option * that are on the market at this time*

Considering you only need 320 CFM to make 650HP, and all of the Aftermarket G3 heads exceed the capabilities of the available off the shelf cams ......... off the shelf Apache(BGE) has you covered ,

Eagle head advantage, is the 65CC chamber, with 2.125X6mm intake valve and great port job, 365/370CFM @ .650 lift is achievable...but not cheep,
Pre-Eagle heads can get up in the 330CFM area , but there's no decent Intake manifold to take advantage of the flow.

Side note ,
DRS sells the Drag pak head for $5k bare , but they do flow 400/260CFM @ .650 lift. BlackBird Cast heads are $3500 and they claim same Flow #s same as DSR ,

Only you know what you are willing to spend.


Truth has no agenda, but those with an agenda make their own truth.
Some of us are so open minded they only see their View



Re: engine plans [Re: ric3xrt] #3280712
01/05/25 01:44 PM
01/05/25 01:44 PM
Joined: Jan 2006
Posts: 1,405
Trumbauersville PA
ric3xrt Offline
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ric3xrt  Offline
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Trumbauersville PA
Back in 2020 like every one else I had a lot of spare time on my hands, built four different "426" combos and the advantage of owning my own 902Dyno I kept myself busy. these were all built and dyno'd in April.
1) 5.7 block, 4.00X4.25(427.257) 12.3 to 1 , HP610@6200TQ600@4800
2) 6.1 block, 4.08X4.08(426.738) 12.1 to 1 HP645@6800TQ585@5400
3) 6.1 block, 4.09X4.05(425.679) 12.2 to 1 HP640@6900TQ580@5400
4) 6.1 block ,4.165X3.9(425.084) 12.3 to 1 HP660@7000TQ570@5600(w/Darton MID sleeves)
All 4 used the same heads/cam/Intake manifold Holley 950 mech secondary carb, after each dyno session, the top end was removed and used on the next short block ,cam removed and re-degreed in each different short block.
heads, were Apache, port matched to a Prefix single plane intake, Manley stainless stock size valves, PSI 1516 spring, new valve job, spring ht and loads were all matched
Cam was .620/.640 250/260 110LSA.

All Results are an average of 10 pulls. #1 had the best BSFC ,and made peak TQ with just 18^ of timing.

I've a done a few 4.125X4.00(427.64) BGE block builds, last one was back in Sep of this year , out of the box AFR 224CC Blackhawk heads, Comp Cams 112-337-11 .635/.635 229/241@.50 117 LSA , made 660@6500 585@5000
Holley Hi-Ram with a 105mmTB its in a 2013 Challenger M6 car stock PCM(with tune)


Truth has no agenda, but those with an agenda make their own truth.
Some of us are so open minded they only see their View



Re: engine plans [Re: ric3xrt] #3280721
01/05/25 02:04 PM
01/05/25 02:04 PM
Joined: Jan 2006
Posts: 1,405
Trumbauersville PA
ric3xrt Offline
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ric3xrt  Offline
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a Well built 392(BGE) build will get you to low 600's with off the shelf parts and ported heads, expect to spend about 7k and 8k for a 426ci build.
12.5 to 1 is about the highest compression for 93oct. with the 4.09+ bore.
All of the 4.05 cranks out there will take 700hp ,
DSS/Manley/Diamond all have good track recorded with the G3 pistons, one thing to avoid are 8cc+ Dome pistons, they need a lot of reshaping to work with out detonation issues.

I'm doing a Dart block build next week, the owner wants to do 4.25X3.75, Crank is a SRT392 offset ground to 3.75 ,2.0 Rod journal, 6.30 in rods Pistons are 1.12 pin height., right now the plan is to use a set of BGE heads that were done by HHP , Cam is a copy of the old Racer Brown STX22.


Truth has no agenda, but those with an agenda make their own truth.
Some of us are so open minded they only see their View



Re: engine plans [Re: ric3xrt] #3280983
01/06/25 03:14 PM
01/06/25 03:14 PM
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Canada
WO23Coronet Offline
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Originally Posted by ric3xrt
Back in 2020 like every one else I had a lot of spare time on my hands, built four different "426" combos and the advantage of owning my own 902Dyno I kept myself busy. these were all built and dyno'd in April.
1) 5.7 block, 4.00X4.25(427.257) 12.3 to 1 , HP610@6200TQ600@4800
2) 6.1 block, 4.08X4.08(426.738) 12.1 to 1 HP645@6800TQ585@5400
3) 6.1 block, 4.09X4.05(425.679) 12.2 to 1 HP640@6900TQ580@5400
4) 6.1 block ,4.165X3.9(425.084) 12.3 to 1 HP660@7000TQ570@5600(w/Darton MID sleeves)
All 4 used the same heads/cam/Intake manifold Holley 950 mech secondary carb, after each dyno session, the top end was removed and used on the next short block ,cam removed and re-degreed in each different short block.
heads, were Apache, port matched to a Prefix single plane intake, Manley stainless stock size valves, PSI 1516 spring, new valve job, spring ht and loads were all matched
Cam was .620/.640 250/260 110LSA.

All Results are an average of 10 pulls. #1 had the best BSFC ,and made peak TQ with just 18^ of timing.

I've a done a few 4.125X4.00(427.64) BGE block builds, last one was back in Sep of this year , out of the box AFR 224CC Blackhawk heads, Comp Cams 112-337-11 .635/.635 229/241@.50 117 LSA , made 660@6500 585@5000
Holley Hi-Ram with a 105mmTB its in a 2013 Challenger M6 car stock PCM(with tune)









Why did the 5.7 based "426" make so much less hp? due to the smaller bore?

Last edited by WO23Coronet; 01/06/25 03:15 PM.
Re: engine plans [Re: ric3xrt] #3280985
01/06/25 03:21 PM
01/06/25 03:21 PM
Joined: Jan 2008
Posts: 4,290
Canada
WO23Coronet Offline
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WO23Coronet  Offline
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Canada
Originally Posted by ric3xrt
Back in 2020 like every one else I had a lot of spare time on my hands, built four different "426" combos and the advantage of owning my own 902Dyno I kept myself busy. these were all built and dyno'd in April.
1) 5.7 block, 4.00X4.25(427.257) 12.3 to 1 , HP610@6200TQ600@4800
2) 6.1 block, 4.08X4.08(426.738) 12.1 to 1 HP645@6800TQ585@5400
3) 6.1 block, 4.09X4.05(425.679) 12.2 to 1 HP640@6900TQ580@5400
4) 6.1 block ,4.165X3.9(425.084) 12.3 to 1 HP660@7000TQ570@5600(w/Darton MID sleeves)
All 4 used the same heads/cam/Intake manifold Holley 950 mech secondary carb, after each dyno session, the top end was removed and used on the next short block ,cam removed and re-degreed in each different short block.
heads, were Apache, port matched to a Prefix single plane intake, Manley stainless stock size valves, PSI 1516 spring, new valve job, spring ht and loads were all matched
Cam was .620/.640 250/260 110LSA.

All Results are an average of 10 pulls. #1 had the best BSFC ,and made peak TQ with just 18^ of timing.

I've a done a few 4.125X4.00(427.64) BGE block builds, last one was back in Sep of this year , out of the box AFR 224CC Blackhawk heads, Comp Cams 112-337-11 .635/.635 229/241@.50 117 LSA , made 660@6500 585@5000
Holley Hi-Ram with a 105mmTB its in a 2013 Challenger M6 car stock PCM(with tune)






I see LSA's all over the place for the Gen3's. The SBE cams seem to use a wider LSA for P to V clearance. What do these engines like? I know the more efficient the heads are the less they need to rely on a tight LSA and the pulling of the exhaust on overlap for cylinder filling. In two of your examples,, one uses a 110 LSA, while another uses 117, with similar hp outputs

Re: engine plans [Re: WO23Coronet] #3281011
01/06/25 06:19 PM
01/06/25 06:19 PM
Joined: Jan 2005
Posts: 12,554
Kalispell Mt.
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HotRodDave Offline
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Kalispell Mt.
Originally Posted by WO23Coronet
Originally Posted by ric3xrt
Back in 2020 like every one else I had a lot of spare time on my hands, built four different "426" combos and the advantage of owning my own 902Dyno I kept myself busy. these were all built and dyno'd in April.
1) 5.7 block, 4.00X4.25(427.257) 12.3 to 1 , HP610@6200TQ600@4800
2) 6.1 block, 4.08X4.08(426.738) 12.1 to 1 HP645@6800TQ585@5400
3) 6.1 block, 4.09X4.05(425.679) 12.2 to 1 HP640@6900TQ580@5400
4) 6.1 block ,4.165X3.9(425.084) 12.3 to 1 HP660@7000TQ570@5600(w/Darton MID sleeves)
All 4 used the same heads/cam/Intake manifold Holley 950 mech secondary carb, after each dyno session, the top end was removed and used on the next short block ,cam removed and re-degreed in each different short block.
heads, were Apache, port matched to a Prefix single plane intake, Manley stainless stock size valves, PSI 1516 spring, new valve job, spring ht and loads were all matched
Cam was .620/.640 250/260 110LSA.

All Results are an average of 10 pulls. #1 had the best BSFC ,and made peak TQ with just 18^ of timing.

I've a done a few 4.125X4.00(427.64) BGE block builds, last one was back in Sep of this year , out of the box AFR 224CC Blackhawk heads, Comp Cams 112-337-11 .635/.635 229/241@.50 117 LSA , made 660@6500 585@5000
Holley Hi-Ram with a 105mmTB its in a 2013 Challenger M6 car stock PCM(with tune)


The factory valves in the BGE, Apache and hellcat heads are very close to the bore at low lift on a 5.7 block and definitely reduce flow down low. They also cause a lot of turbulance and are probably why the TQ is higher number and lower RPM in that combo.









Why did the 5.7 based "426" make so much less hp? due to the smaller bore?


I am not causing global warming, I am just trying to hold off a impending Ice Age!



Re: engine plans [Re: cha1lenger] #3281091
01/07/25 09:14 AM
01/07/25 09:14 AM
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maryland
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mhead Offline
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I have the same questions about the gen3 as the op.

I'm a bracket racer racing small blocks for a long time 30 plus years.My son and I both run two bracket style points programs at our local track.I have the same questions.
I'm only interested in na builds.

Why doesn't anyone make higher lift cams with a head that flows this much?Are the valves too short to get higher lifts?

I would think with the head flow these engines should make more na power.

Re: engine plans [Re: mhead] #3281155
01/07/25 12:59 PM
01/07/25 12:59 PM
Joined: Jan 2003
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RTSE4ME Offline
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With oem lifter .650 is the highest you can go on lift.
ric3xrt did a good & informative video on rocker motion.
Jesel makes nice lifters and rockers for an all out n/a build.

Re: engine plans [Re: mhead] #3281212
01/07/25 04:35 PM
01/07/25 04:35 PM
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Posts: 4,290
Canada
WO23Coronet Offline
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WO23Coronet  Offline
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Rockers get funky when you approach .650" of lift. As said, you can get higher capability rockers but it's pricey

Re: engine plans [Re: WO23Coronet] #3281261
01/07/25 07:17 PM
01/07/25 07:17 PM
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Michigan
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cha1lenger Offline OP
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Michigan
Wow I get back from vacation and see a bunch of amazing replies to this!

I plan to be running methanol fuel, some people had asked that. I plan to run higher compression like 11 or 12:1. Nothing too crazy but should still be very mild with alcohol.

Cams have come up several times. I am most familiar with small block Mopar. They very routinely have cams with LSA 107, 108 in a higher performance application. For gen 3, there is almost none below 112. I am wondering why that is, why they still sound good and rev with what would be a truck cam in a small block from a LSA perspective. I know theres a ton to the cam equation and I am not a cam guru by any shape or form.

I know the beauty of gen 3 hemis (apart from the incredible BGE block) is how great the heads are stock. My issue is by the time I buy cores for $1200-1500, have them gone thru, replace valves and springs, its getting close to what aftermarket ones run. for $3500 Blackbird is claiming to have turn key heads ready to go that I would expect are stronger and better than the already incredible 6.4 heads. A lot to consider, for sure!!! There isn't a ton of literature out on this engine, compared to older Mopar and certainly GM especially LS which is a contemporary. I do predict gen 3 hemi will take off and the aftermarket support is ratcheting up exponentially. I appreciate all the wisdom shared thus far!

Last edited by cha1lenger; 01/07/25 07:19 PM.
Re: engine plans [Re: RTSE4ME] #3281362
01/08/25 10:10 AM
01/08/25 10:10 AM
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Quakertown PA
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Tay Offline
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Originally Posted by RTSE4ME
With oem lifter .650 is the highest you can go on lift.
ric3xrt did a good & informative video on rocker motion.
Jesel makes nice lifters and rockers for an all out n/a build.


https://www.youtube.com/watch?v=O_jkrntaJ3I is the video he's referencing

Re: engine plans [Re: mhead] #3281367
01/08/25 10:29 AM
01/08/25 10:29 AM
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Quakertown PA
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Tay Offline
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Originally Posted by mhead
I have the same questions about the gen3 as the op.

I'm a bracket racer racing small blocks for a long time 30 plus years.My son and I both run two bracket style points programs at our local track.I have the same questions.
I'm only interested in na builds.

Why doesn't anyone make higher lift cams with a head that flows this much?Are the valves too short to get higher lifts?

I would think with the head flow these engines should make more na power.




Lift is limited for two reasons , one is the length OEM lifter bore and lifter , if you have a cam base circle smaller than( don't quote me been a awhile) 1.56 the lifters will fall out of the plastic tray/retainer. on the other end of it is the location of the shafts and the tip of the valve , the arc of motion at .670 Gross lift loses contact with the head of the valve , Lash caps can only add so much to the contact area.
the other issue and it's more of a If you get there here's the next hill to climb , The OEM heads will only support 450lbs of spring pressure,

When we run the pedestal mount Jesel rocker system, we can add a spacer under the valve spring (and longer Valves) and you can go as high as .800 lift....Keep in mind you just added 5k for the rocker system and a minimum 2k-3k in specialty lifters.

Re: engine plans [Re: HotRodDave] #3281377
01/08/25 10:50 AM
01/08/25 10:50 AM
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Quakertown PA
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Originally Posted by HotRodDave
Originally Posted by WO23Coronet
Originally Posted by ric3xrt
Back in 2020 like every one else I had a lot of spare time on my hands, built four different "426" combos and the advantage of owning my own 902Dyno I kept myself busy. these were all built and dyno'd in April.
1) 5.7 block, 4.00X4.25(427.257) 12.3 to 1 , HP610@6200TQ600@4800
2) 6.1 block, 4.08X4.08(426.738) 12.1 to 1 HP645@6800TQ585@5400
3) 6.1 block, 4.09X4.05(425.679) 12.2 to 1 HP640@6900TQ580@5400
4) 6.1 block ,4.165X3.9(425.084) 12.3 to 1 HP660@7000TQ570@5600(w/Darton MID sleeves)
All 4 used the same heads/cam/Intake manifold Holley 950 mech secondary carb, after each dyno session, the top end was removed and used on the next short block ,cam removed and re-degreed in each different short block.
heads, were Apache, port matched to a Prefix single plane intake, Manley stainless stock size valves, PSI 1516 spring, new valve job, spring ht and loads were all matched
Cam was .620/.640 250/260 110LSA.

All Results are an average of 10 pulls. #1 had the best BSFC ,and made peak TQ with just 18^ of timing.

I've a done a few 4.125X4.00(427.64) BGE block builds, last one was back in Sep of this year , out of the box AFR 224CC Blackhawk heads, Comp Cams 112-337-11 .635/.635 229/241@.50 117 LSA , made 660@6500 585@5000
Holley Hi-Ram with a 105mmTB its in a 2013 Challenger M6 car stock PCM(with tune)


The factory valves in the BGE, Apache and hellcat heads are very close to the bore at low lift on a 5.7 block and definitely reduce flow down low. They also cause a lot of turbulance and are probably why the TQ is higher number and lower RPM in that combo.









Why did the 5.7 based "426" make so much less hp? due to the smaller bore?


Dave's partially correct, the other factor is it's an "under Square" bore/stroke combination , you'll see it also 3.9xx X 4.05 (5.7 Block) 39X CI Builds compared to 4.09/4.10X3.72(6.4 block) 39X CI builds with the same heads and camshaft.

For example ,3.937X4.05 = 394ci, while 4.10X3.72 =393ci , with Eagle heads on both , the 393 Peak HP will be roughly 10hp more at a higher RPM, Apache/BGE heads it'll be a difference of roughly 15 Hp , again this is example not absolute.

Re: engine plans [Re: WO23Coronet] #3281383
01/08/25 11:21 AM
01/08/25 11:21 AM
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Tay Offline
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A comment on why All G3 cams have wide LSA ,

All of the current Cam offerings are geared towards Computer controlled engine management systems, tight LSA is hard to tune on the OEM systems.

Hughes Engines was the only one to offer new Non-EFI cams , some of their high lift cams had LSA's around 108-110, they stopped selling their G3 cams a few years ago, I guess they just didn't sell well. there's a guy on Ebay that sells reground Non-VVT cams , some of his grinds work great in carburetor applications.

The narrower LSA and large Exhaust valve pulls enough intake charge out at higher RPMs to effect how I tune an EFI G3 especially a OEM ECU/PCM , the NGC3(&4) is less effected but the GPEC(s) have more hidden emissions tables that don't like excess unburnt fuel........ while a Carb/MSD Hemi-6 doesn't seem to care. One of the G3 advantages over the G2 is the shallower valve angles don't pull as hard on the Intake charge coming in when you get above 65000RPMs , but it still pulls harder one the intake charge than a SBM or BBM , it's about the same as a 351C 4V , some of the more aggressive 351C roller cam profiles transfer over well to the G3 platform.....(just saying)

I've said before I prefer Eagle heads to Apache(in a NA build) this is one of the reasons, If I build a 392 for a 2014 Challenger, I can make more overall Power/Tq with 340CFM Eagles then I can 340CFM Apache/BGE

Re: engine plans [Re: Tay] #3281506
01/08/25 06:17 PM
01/08/25 06:17 PM
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maryland
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mhead Offline
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This is all great info gentlemen.

The prefix intake in a 4500 flange has me interested in carb form.To me if the heads are flowing 400 cfm the 4500 flange would be beneficial.I also run e85 that's available from the pump that always test good.

Keep the info coming so we all can learn please.

Re: engine plans [Re: mhead] #3281810
01/10/25 08:04 AM
01/10/25 08:04 AM
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STEFF Offline
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Here are some simple tips/things I've learned since building my first NA Gen 3 Hemi in 2010.

1. Blocks, all the G3 Hemi blocks can handle anything you want to throw at it for an NA combo. 5.7, 6.1, 6.4 Scat Pack, BGE or Hellcat. One of the motors I have is a carbed 357" 5.7 based motor with ported BGE heads on Nitrous that with a .036 jet fogger, is making about 1100hp. So don't get hung up on having to have a BGE block.

2. Heads, Ported Eagle, Apache or BGE heads work fantastic. I've been using Craig Thibeau, who owns Thitek for my cylinder head needs for a decade. He was the first in the Gen 3 market to develop his own aftermarket head called the Big Bear, about 2012?, which I own a pair and have been fantastic and make great power. But, I also have used his ported factory offerings and they all have been great. Eagles have a 2.10 dia. intake valve. Apache's and BGE's have a 2.14 dia. intake valve. You can also have larger valves put in the stock castings too, if needed. My ported BGE's have 2.18 dia. intakes in them. The aftermarket offerings are all pretty good, but again I'm partial to Thitek and they have various port/valve size versions to suit many applications. Feel free to reach out to me if you want contact info for him.

3. Rockers, bang for the buck, the stock valve train is very stable and reliable for what you want to do. They even have proven to handle plenty of power thru 1500-1600hp with power adder builds. I'd never talk anyone out of going T & D or Jesel for adjustable rockers, but they are a few bucks.

3. Camshafts, don't get caught on lobe center numbers, they are a resultant of the valve events design, not a design criteria. All the cams I've had were 112 or greater, for my NA combos. Keep the lobe lift to .400 /.410 max, which is about .650 lift. The stock rockers can't really handle much more than that with the sweep of the stock rocker. Pick your cam company you are most comfortable with and ride with them. Gen 3's are not magic, they're just another motor and any competent cam company can supply you a cam that fits the application.

4. Lifters, do yourself a favor and get the Johnson Short travel lifters with axle oiling #ST2356. They are the BEST hydraulic roller lifter for the Gen 3. BUT, when using short travel lifters, you need to measure every pushrod position for the length as the preload is only .030" +/- .005". And don't be shocked by having to order various different length pushrods. The last motor I just finished up had 6 different lengths needed, I use Manton for my Custom length pushrods.

5. Every NA comb I've had, at minimum peak HP was 7000 for my mildest combo to 7600 for my wildest combo. For a 700-750 combo, it'll probably be around 7200-7400 range. Shift at 75-7700 and you're rocking!

6. Intake manifold, depends on if you plan carb or EFI. The Ritter or Prefix Drag Pack Intake with a Dominator carb flange is my go-to 100% of the time. Unless you build enough motor and to want to venture into a tunnel ram, The Holley Hi-Ram is a great piece.

7. Crankshafts, I try to never go past 4" max on the stroke. Even at 4" stroke, due to the cylinder wall length, the piston skirts take a beating and there is nothing you can do about it, due to the piston sticking out of the bore at the bottom of the piston crank travel. Callies Compstar and Molnar Technologies are both great products.

8. Rods, any good H-Beam works well. Just like the crank, Callies and Molnar are my go to's.

9. Pistons, I'm a Diamond guy, but all the piston companies offer nice pieces. Pick your poison. If you plan on running alcohol, I'd go 14:1 easily on compression, On my gas applications, street / strip combos, I usually go 12-12.5:1. Run 93 on the street (when driving sane) and race fuel at the track and on the street (when beating on it). On race only gas applications, 14-15:1 compression.

10. Oil Pumps. Melling has plenty of offerings that work well.

Off the top of my head, these basics should help you. Enjoy!!




Last edited by STEFF; 01/10/25 08:12 AM.
Re: engine plans [Re: WO23Coronet] #3281846
01/10/25 11:32 AM
01/10/25 11:32 AM
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Kalispell Mt.
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HotRodDave Offline
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Originally Posted by WO23Coronet
Rockers get funky when you approach .650" of lift. As said, you can get higher capability rockers but it's pricey



The bright side of the soft .650 lift limit (I call it a soft limit because you can do more but it gets really expensive really fast) is it is less critical than other engine platforms because the hemi flow at lower lifts is insane, there is nothing that can flow as much at .300 and .400 so what you are used to needing on other engines for a certain power don't apply here. An LS3 is the best readily available chevy LS head for example it has about 50 CFM on it at just .300 lift and .400 lift the hemi is outflowing it by 285 to 265 and even at .600 still has it by 10 CFM so if you had the same cam the hemi will start accelerating the air charge into the chamber at lower lift and that inertia will help the head flow more at peak lift in a real world dynamic situation. The common everyday BGE truck head still flows more than the LS7 factory CNC ported head and is about the same at higher lift and those only came in a few Corvette and Camaros. The low lift flow is one reason the LSA is wider than wedges, no point in flowing so much air into the chamber while the exhaust port is still open. The big tuning problem with MPFI is the fuel is the first thing in the chamber when the valve opens because the fuel is squirted on the back of the closed intake valve and if the exhaust is open the fuel flows (not all of it but a significant portion) out the exhaust then the ex valve closes and traps a lean mix in it but the exhaust O2 reading is still gonna show a normal A/F ratio, you mitigate this with wider LSA, same thing happens on a wedge but it is more dramatic in a hemi with it's great low lift flow.


I am not causing global warming, I am just trying to hold off a impending Ice Age!



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