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498 cid 440 stroker build formula
Posted By: torqueaddict
498 cid 440 stroker build formula - 06/28/12 03:09 AM
Hey guys, heres my build I wanna see what you guys think. I am building a 498 stroker from a 440 made by hughes engines. The kit is 4.15 stroke with I beam rods. Flat top pistons. I am using the 440 source stealth heads in theyre standard form, they have an 80cc. The cam I have is the Lunati 60303 cam. Here is the specs:Advertised Duration (Int/Exh): 268/276
Duration @ .050 (Int/Exh): 226/234
Gross Valve Lift (Int/Exh): .494/.513
LSA/ICL: 110/106
Valve Lash (Int/Exh): Hyd/Hyd
RPM Range: 1800-6200
I am running a 727 trans with a 2400 stall and 323 gears. I am really concerned that my compression will be far to high. I am trying to run on pumped gas without detonation. The guy from Hughes said I can run pumped gas with this really huge cam. I want a steady idle and dont want to sound like my car is dying out. What do you guys think? I have the option of sending the flat tops back along with the crank to get dish pistons and have it all balanced. I am a little upset because I told him I want a pump gas motor and he sent me flat top pistons anyway. Maybe you guys have some ideas on how to lower my compression and make this thing work without sending it back. Thanks in advance for the help guys.
Posted By: ahy
Re: 498 cid 440 stroker build formula - 06/28/12 03:25 AM
There are lots of variables in figuring compression and more in estimating detonation potential... but in your case I'd say no way on pump gas.
With 80'ish cc heads and 4.15+ stroke you will just about always need a decent size dish piston for pump gas. As a guess, you are around 11.5 CR with the flat top. With a smaller performance cam, you should be at 10 or maybe less depending on quench for pump gas.
I'd send it back and get the dish piston. If you have measurements on your engine - deck height, rod length - and know the piston specs - compression height and dish or valve relief volume - CR can be calculated more accuratly.
Bottom line, flat top on a stroker is normally a race gas only setup.
Posted By: Dcuda69
Re: 498 cid 440 stroker build formula - 06/28/12 03:30 AM
Quote:
There are lots of variables in figuring compression and more in estimating detonation potential... but in your case I'd say no way on pump gas.
With 80'ish cc heads and 4.15+ stroke you will just about always need a decent size dish piston for pump gas. As a guess, you are around 11.5 CR with the flat top. With a smaller performance cam, you should be at 10 or maybe less depending on quench for pump gas.
I'd send it back and get the dish piston. If you have measurements on your engine - deck height, rod length - and know the piston specs - compression height and dish or valve relief volume - CR can be calculated more accuratly.
Bottom line, flat top on a stroker is normally a race gas only setup.
I have a dish in my Diamonds in a 470"(low deck) with Eddy heads at 84cc...puts me at 10.2:1 which works great on pump swill. 
Posted By: moparmojo
Re: 498 cid 440 stroker build formula - 06/28/12 03:31 AM
Is 11:1 too high with aluminium heads?
Posted By: DaytonaTurbo
Re: 498 cid 440 stroker build formula - 06/28/12 03:37 AM
I ran the 60303, it's not an aggressive cam for a 440. Tiny for a 493. I'd be looking more at the 60305.
Posted By: Dcuda69
Re: 498 cid 440 stroker build formula - 06/28/12 03:38 AM
"Is 11:1 too high with aluminium heads?"
I think that depends on what your plans are. I wanted to make sure I can ALWAYS be able to buy fuel so I went pretty conservative(mine runs fine on 89, found that out by an oops
)If your plans are always being able to run race gas or premium fuel(or any type of combo)you can be more aggressive. I have no idea what pump swill will be in the years to come, so I stayed conservative.
Posted By: 300by500
Re: 498 cid 440 stroker build formula - 06/28/12 04:13 AM
My 4.15 crank / .040 over 498 RB has relieved pistons at zero deck, and it will be about 11:1 with 84cc Edelbrocks. It has a Hughes 246/250 duration hydraulic cam (.614 / .610 lift with the 1.6 Harland Sharps)
If you have 80cc heads and your pistons are near the top of the bore, I'd guess you'll be over 11:1 compression, which is about as high as you want to go with 93 octane.
Posted By: torqueaddict
Re: 498 cid 440 stroker build formula - 06/28/12 04:19 AM
Quote:
My 4.15 crank / .040 over 498 RB has relieved pistons at zero deck, and it will be about 11:1 with 84cc Edelbrocks. It has a Hughes 246/250 duration hydraulic cam (.614 / .610 lift with the 1.6 Harland Sharps)
If you have 80cc heads and your pistons are near the top of the bore, I'd guess you'll be over 11:1 compression, which is about as high as you want to go with 93 octane.
The 440source stealth heads claim to have 80cc heads, I hope not. If they dont that will help my issue.
Posted By: torqueaddict
Re: 498 cid 440 stroker build formula - 06/28/12 04:23 AM
Quote:
I ran the 60303, it's not an aggressive cam for a 440. Tiny for a 493. I'd be looking more at the 60305.
Will that 60305 cam give me a smooth idle with lots of low end torque?
Posted By: torqueaddict
Re: 498 cid 440 stroker build formula - 06/28/12 04:30 AM
Quote:
There are lots of variables in figuring compression and more in estimating detonation potential... but in your case I'd say no way on pump gas.
With 80'ish cc heads and 4.15+ stroke you will just about always need a decent size dish piston for pump gas. As a guess, you are around 11.5 CR with the flat top. With a smaller performance cam, you should be at 10 or maybe less depending on quench for pump gas.
I'd send it back and get the dish piston. If you have measurements on your engine - deck height, rod length - and know the piston specs - compression height and dish or valve relief volume - CR can be calculated more accuratly.
Bottom line, flat top on a stroker is normally a race gas only setup.
The machine shop is going to measure out everything and see where we are at. After that I will make a decision. I am upset about the extra cost because he sent me the wrong stuff. This really sucks.
Posted By: 2fast4yourBrain
Re: 498 cid 440 stroker build formula - 06/28/12 04:54 AM
Stupid question, but can you install a super thick head gasket to lower compression ratio? Or will that screw up quench?
Posted By: torqueaddict
Re: 498 cid 440 stroker build formula - 06/28/12 05:35 AM
Quote:
Stupid question, but can you install a super thick head gasket to lower compression ratio? Or will that screw up quench?
Im not sure but I think your correct. Thats what my buddy told me.
Posted By: BIG-MIKE-500 ci
Re: 498 cid 440 stroker build formula - 06/28/12 08:23 AM
Hi Anthony. That cam is far too small for those cubes. I have a 493ci Stroker. I use "Diamond Piston" part#52415 which has an effective dish of -12:5cc. I have a deck clearence of 2 thou; & using Comp Cams 294S which is
248@050" & with the cam installed straight-up, has a cranking pressure of 185 lbs. On pump gas this is close to as much pressure that you want to go.
I use Stealth Heads(standard)it idles at 800rpm & with 2:75 gears in an Aussie Charger with myself & fuel weighs in at near 4000lbs, with 4-speed New-Process does 12:00-12:30@ 117-118mph in the 1/4 & 92mph at the 1/8 mile mark.
I also get 17mpg Imperial(approx 15US). 2260 revs @ 62mph.
I believe you will have regrets with a cam that small. It is even small in a 440 so it will just starve a 493ci.
Mike in New Zealand
Posted By: 300by500
Re: 498 cid 440 stroker build formula - 06/28/12 11:35 AM
Quote:
Hi Anthony. That cam is far too small for those cubes. I have a 493ci Stroker. I use "Diamond Piston" part#52415 which has an effective dish of -12:5cc. I have a deck clearence of 2 thou; & using Comp Cams 294S which is [Email]248@050"[/Email] & with the cam installed straight-up, has a cranking pressure of 185 lbs. On pump gas this is close to as much pressure that you want to go.
I use Stealth Heads(standard)it idles at 800rpm & with 2:75 gears in an Aussie Charger with myself & fuel weighs in at near 4000lbs, with 4-speed New-Process does 12:00-12:30@ 117-118mph in the 1/4 & 92mph at the 1/8 mile mark.
I also get 17mpg Imperial(approx 15US). 2260 revs @ 62mph.
I believe you will have regrets with a cam that small. It is even small in a 440 so it will just starve a 493ci.
Mike in New Zealand
12 flat quarters in a 4000 lb car with 2.75 gears! THAT is why I love strokers!
You're right about the cam...
Posted By: J_BODY
Re: 498 cid 440 stroker build formula - 06/28/12 02:01 PM
If you have a set of stock LY rods laying around I wouldn't be the least worried about using them at the power level you are shooting for. The stock rods are still alive and well in my old car and it's running low 10's.
Posted By: torqueaddict
Re: 498 cid 440 stroker build formula - 06/28/12 03:09 PM
Quote:
Hi Anthony. That cam is far too small for those cubes. I have a 493ci Stroker. I use "Diamond Piston" part#52415 which has an effective dish of -12:5cc. I have a deck clearence of 2 thou; & using Comp Cams 294S which is [Email]248@050"[/Email] & with the cam installed straight-up, has a cranking pressure of 185 lbs. On pump gas this is close to as much pressure that you want to go.
I use Stealth Heads(standard)it idles at 800rpm & with 2:75 gears in an Aussie Charger with myself & fuel weighs in at near 4000lbs, with 4-speed New-Process does 12:00-12:30@ 117-118mph in the 1/4 & 92mph at the 1/8 mile mark.
I also get 17mpg Imperial(approx 15US). 2260 revs @ 62mph.
I believe you will have regrets with a cam that small. It is even small in a 440 so it will just starve a 493ci.
Mike in New Zealand
One of the members from cuda challenger uses that cam. He says he really likes the cam. I changed it and went a step up just to be safe. He said my compression would be too high even if I bring it below 11:1. So I went with the next one up. I am not sure where the piston sits in the hole however I think I am just going to send them back and get the dished pistons.
Posted By: Silver70
Re: 498 cid 440 stroker build formula - 06/28/12 06:01 PM
I had a 499, edelbrock heads, mp 590 cam, 11 to 1 compression and it ran fine on 93 octance.
Posted By: torqueaddict
Re: 498 cid 440 stroker build formula - 06/28/12 07:01 PM
I live in California, we dont have 93 octane. And I think the stealth heads have smaller cc so I would actually be closer to 11 1/2 to one. I already shipped back the crank and the pistons in favor of dish pistons.
Posted By: BIG-MIKE-500 ci
Re: 498 cid 440 stroker build formula - 06/28/12 08:11 PM
Mike in New Zealand here.
Anthony, here is a run-down of my set-up.
I run a Comp Cams solid,248@050"; 76 overlap on 110 centers. RB Stroker 496;10:8-1 with 187 lbs cranking pressure. I've champhered the top of the bore beside the inlet valve down to top of top ring.(I believe it helps Cylinder filling)
Stock 440 Source Stealth Heads; 1-7/8" Headers; Weiand Xcelerator with 850 Holley(4781).
It idles at 800rpm.
My car is an Australian Charger weighing with myself & fuel a nudge over 4000lbs.
I have New-Process 4-Speed with 2:75 geared 9inch out back.
It runs 12:00-12:25@117-118:50mph 1/4 mile & 91-92mph 1/8th mile with 2:0sec 60ft every run.
I use a 650(4777)Holley on the street & get 17 mpg Imperial. Thats probably about 15 mpg to a US Gallon.
Also; on a chassis dyno the 650 was only 13 HP down on the 850.
I suspect this is because the cam reads quite small in the stroker versus the 440.
Another thing also; the Cam! A 110 Lobe Seperation is probably better for you as well. Better drivability & I have 12 inches vacumn at idle & 18 inches @ 75mph.
I shift at 6000 as it's laying down by 5800 due to the cam being small for the engine size.
Also, all parts except the short block, including the cam, I use to run in a 440 prior to this build.
It went 13:00 @ 113mph. It also did 160mph measured in a Car Club Flying 1/4 Mile.
Incidentily; one day I arrived late for one of these flying 1/4's so did my first run with the 650 & it run through at 160 MPH & next run with the 850 did exactly the same speed.
The jets in the 850 are 77's as I had to lean it down from standard 80's to up the exhaust temps in the header probes. I have sensor plugs on each header about 4 inches from exhaust ports.
Probably because the rod ratio is more like a Big-Block Chev & creates more draw as the piston goes away from TDC faster I suspect why it needed leaning out.
I took a guess on what I could get away with on this combo so as to just run ordinary pump gas & because my "quench" is damn good,it is close to the limits of cylinder pressure.
Slightly big in cam choice would likely give more power, but being to small,& you might lose the engine because of detonation.
In the near future I'm going to get a set of Stealth CNC'ed Heads & up the cam to mid 250's@ 050 with over 0:600 lift as they seem to really up the Torque & Power.
Because it's mainly a street car is why I'm chasing Torque & good fuel consumption & not "all out 1/4 times.
My 2:75 gears only slow the first 60 to 80ft on launch & then it's long gears & great fun.
Hope this is of help & interest.
Posted By: 72blubird
Re: 498 cid 440 stroker build formula - 06/28/12 08:16 PM
Big Mike what kind of vacuum pressure do you have?
Also does anyone know what the stealth head CCs really are? Tried to measure them but the syringe used was not the best and am not sure.
You can definitely use different thickness of head gaskets for compression change.
Posted By: BIG-MIKE-500 ci
Re: 498 cid 440 stroker build formula - 06/28/12 08:31 PM
Reading back through my previous post,I feel the "Head Flow" is probably more a limit to more power & revs with this cam than the size of the Cam itself.
I have my distributor set-up with a light spring. It has 20 degrees initial for starting & instantly goes to 36 once running. In top gear I can go to full-throttle once I'm up to about 1800 without getting the "clatters"(pinking).
Posted By: jose jones
Re: 498 cid 440 stroker build formula - 06/28/12 08:41 PM
In 1996 I built my first 496 from a 440 block, 4.15 crank, eagle H-beam rods,wiseco pistons with a 10.1 compression ratio and B&B lightweight wrist pins (155 grams)instead of about 235 for other pins. The cam was a hydralic 540 something lift Comp cam,Holley 850 DP, I had Mopar Performance stage 1 heads with a set of stamped steel rocker arms and a Carter high volume fuel pump. 6 quart Hemi oil pan,high volume MP oil pump, with 3 inch full exhaust,I drove it a bunch on the street and at the track it ran 11.7 @117 MPH on pump gas and never broke in 15 years of abuse, it also would rev like a 340. I would suggest on your motor Harland Sharp rockers and Indy ported SR-295 Heads they work great and flow good numbers, a light rotating assembly is the key, the guy that now owns the motor is still running it today, I went to the finals racing it at Mopars at the Strip and the semi finals at the Mopar Nationals it was even features in Car Craft in Mar 2003 I have also built 572 stroker motors this 496 is your best bang for the buck, the car ran great on super unleaded it is a red 69 Road Runner with a 727 2500 stall converter 354 gears in a Dana 60
Posted By: BIG-MIKE-500 ci
Re: 498 cid 440 stroker build formula - 06/28/12 08:43 PM
72blubird: Hi Glen.
That is the one thing I can't remember. I do belive to be 80cc's. It's a few years since I put this motor together.
Vacumn is 12 inches at 800. Plenty for the brake booster.
Any question's, just ask.
Mike
Posted By: 72blubird
Re: 498 cid 440 stroker build formula - 06/28/12 09:29 PM
Sorry op not trying to hijack thread. Reason I asked about vacuum is I am building 470ci 400 block stealth heads 440 source .035 stroker kit. hoping vacuum will be enough hearing your combo is encouraging. Also you said it was a four speed what rpm did you leave the line at?
I will also be at close to 4000lbs with driver using 3.23 gears and a 4 speed. using Comp Cams Xtreme Energy High Lift XE285HL hydraulic flat tappet camAdvertised Duration .285 int .297 ex/Dur @.050; .241 in .247 ex/ Lift .545 in. 545 ex with 1.5 rockers. Lobe Separation Angle 110.
Posted By: 383man
Re: 498 cid 440 stroker build formula - 06/28/12 11:47 PM
Thats a very small cam for a 496. I would go with more cam and it will help keep the cyl pressure down to make it pump gas friendly. I use dished pistons in my 493 and I have 10.6 comp with quench and healthy flat tappet cam that is 264 & 270 @ .050 with .630 lift using 1.6 rockers. I run fine on 92 pump as I only run pump gas. Here is a pic of my dished pistons. Ron
Posted By: gch
Re: 498 cid 440 stroker build formula - 06/29/12 12:15 AM
Add about 10 degrees of duration to that cam and you will have a nice idle with lots of torque everywhere.It will feed the low end and midrange which is where you will need to be with those heads in stock form.
Remember sucking in hot under hood air will put you in detonation much sooner than air from outside the engine compartment.
You can play with timing and rate of advance but something in the 10-10.5-1 range with the added duration will give you a nice mild mannered fun to drive car that will turn into Dr Jekyl when you hammer the gas.
Posted By: torqueaddict
Re: 498 cid 440 stroker build formula - 06/29/12 03:36 AM
Well guys this is the cam chose in this:Hydraulic. Hot Street cam, likes 2800 converter, Hi-Rise type dual plane intake with 850cfm carb, headers, 10:1 compression and 3.73 gears. Likes up to 200HP nitrous.
• Advertised Duration (Int/Exh): 276/284 e
• Duration @ .050 (Int/Exh): 234/242
• Gross Valve Lift (Int/Exh): .513/.533
• LSA/ICL: 110/106
• Valve Lash (Int/Exh): Hyd/Hyd
• RPM Range: 2200-6400
• Includes:
This is slightly bigger than the big last one. I understand many people like big cam, I am just not one of those guys. I want my car to be a sleeper. I also have elected to send the pistons back to Hughes and get the dished pistons with a 13cc in the piston. This should put me at 10.5. I will be happy with that, I think I will enjoty this combo alot. I will have my local engine shop balance the kit using all needed parts. I have one question tho, can I use my 383 harmonic balancer or will I need one specifically for my 440? Thanks guys in advance.
Posted By: rbstroker
Re: 498 cid 440 stroker build formula - 06/29/12 01:39 PM
Sounds like we have similar goals for our strokers. I have mentioned this is another thread. I am going to freshen my 496 stroker this upcoming winter by keeping 500CID Cadillac engine cam specs in mind. I really want max torque down low thinking that it will be a lot more fun to drive on the street with my 4 speed and 3.23 gear. Might even be able to swap to 2.94 or 2.76's. Probably time to swap out my Koffel prepped 906's for Eddy's also. My current setup is a lot of fun, but really more suited for the track than the street.
Posted By: BIG-MIKE-500 ci
Re: 498 cid 440 stroker build formula - 06/29/12 02:13 PM
72bluebird: Glen; I don't like the stress that would go through drive-train with loading the revs & dumping the clutch, so I just sorta hit the peddle from about 1200 revs & do a double bounce on the clutch to launch out without bogging. At one meeting I did 17 runs & every 60ft time was 2:0-2:06 sec's, so I'm very consistant.
Clutch is a Center-Force Dual-Friction which lasted three years of pretty hard launching. Ram Twin-Plate next time for me.
Posted By: BIG-MIKE-500 ci
Re: 498 cid 440 stroker build formula - 06/29/12 02:26 PM
Anthony; I would suggest you opt for having your piston very close to flush with block deck. You "will" make some pretty high pressure with that cam, especially installed advanced 4 degrees.
You will have a better/safer engine with a higher cylinder pressure,if quench is 40-45thou.(ie:Distance between closed chamber face & top of piston). If you go more than this I feel a slightly larger cam may be a safer option.
Pump gas,with good matching of all parts, will support up to 200 lbs Compression. Get the quench wrong & you may need to drop 20 lbs.
Posted By: 72blubird
Re: 498 cid 440 stroker build formula - 06/29/12 03:02 PM
Mike that 60 ft is very good. If I could be that consistent I will be thrilled. Your rpm is right where I was thinking. Had thoughts of trying 1500 but may try a bit lower. What kind of tires do you run? If I get through this and can still afford it I want to get a centerforce clutch have a mcleod now. My brother has a center force and loves it.
Posted By: gch
Re: 498 cid 440 stroker build formula - 06/30/12 02:42 PM
Quote:
Well guys this is the cam chose in this:Hydraulic. Hot Street cam, likes 2800 converter, Hi-Rise type dual plane intake with 850cfm carb, headers, 10:1 compression and 3.73 gears. Likes up to 200HP nitrous.
• Advertised Duration (Int/Exh): 276/284 e
• Duration @ .050 (Int/Exh): 234/242
• Gross Valve Lift (Int/Exh): .513/.533
• LSA/ICL: 110/106
• Valve Lash (Int/Exh): Hyd/Hyd
• RPM Range: 2200-6400
• Includes:
This is slightly bigger than the big last one. I understand many people like big cam, I am just not one of those guys. I want my car to be a sleeper. I also have elected to send the pistons back to Hughes and get the dished pistons with a 13cc in the piston. This should put me at 10.5. I will be happy with that, I think I will enjoty this combo alot. I will have my local engine shop balance the kit using all needed parts. I have one question tho, can I use my 383 harmonic balancer or will I need one specifically for my 440? Thanks guys in advance.
As long as you have an internal balance 383 you can use the same balancer.
That cam will make a mean low end/mid range motor that will probably like to shift in the 5500rpm range.
Think of a stock 440 magnum with headers and now add 100ft lbs.
Posted By: BIG-MIKE-500 ci
Re: 498 cid 440 stroker build formula - 06/30/12 04:37 PM
Glen; I use M/T Streets @ the strip. Hell! On street tires I use to do 200 yard power slides. The crowd loved it! Had no traction so just had some fun for the crowd. Cars beside me were a bit intimidated though! Ha!Ha!
Mike