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Old school 500 cubic inch on the cheap? #208582
01/30/09 12:29 PM
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2boltmain Offline OP
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Before affordable stroker kits mopar guys could..If I recall correctly buy a stroker crank or have a 440 crank welded/regound, use oem 440 rods and smogger off the shelf cast pistons in an RB block. This made 500 cubes. Heavy rotating assembly (compared to current stuff) and not recommended beyond 5500 RPM but a big torquer none the less. My question: Could a cheap stroker (reliable street only engine) be made now with a new stroker crank (under $400) and then oem rods and off the shelf cheap cast low compression 440 pistons? Would the pan rail need clearencing? Bouchillion Performance in the early 90s advertised a stroker kit this way. They recommended the mopar 484 cam and no bigger. Specifically said the 509 made no more power.


Keep old mopars alive.
Re: Old school 500 cubic inch on the cheap? [Re: 2boltmain] #208583
01/30/09 12:40 PM
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I've been on this myself. definitely want cast pistons & I had checked out some 403 olds pistons. 4.351" bore/1.585 CH. they're on eGay for cheap. I'd prefer a B block & I'd have to fab an external oiling system. I haven't found the right combo yet


live every 24 hour block of time like it's your last day on earth
Re: Old school 500 cubic inch on the cheap? [Re: 2boltmain] #208584
01/30/09 02:05 PM
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I don't think you can get parts for less money than a 440Source stroker kit. Maybe if you find a cast piston that works but I'm not so sure there are any. KB might have a cast piston for stroker motors so you could start there.

Re: Old school 500 cubic inch on the cheap? [Re: AndyF] #208585
01/30/09 02:17 PM
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Quote:

I don't think you can get parts for less money than a 440Source stroker kit. Maybe if you find a cast piston that works but I'm not so sure there are any. KB might have a cast piston for stroker motors so you could start there.




Actually Indy is selling a kit right now for LESS and if you look on ebay they are available

Re: Old school 500 cubic inch on the cheap? [Re: JohnRR] #208586
01/30/09 03:35 PM
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The original old school 500 inch was to
get an old caddy 500" engine

logan426

Re: Old school 500 cubic inch on the cheap? [Re: MLR426] #208587
01/30/09 03:37 PM
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Quote:


The original old school 500 inch was to
get an old caddy 500" engine

logan426





Re: Old school 500 cubic inch on the cheap? [Re: 2boltmain] #208588
01/30/09 04:46 PM
01/30/09 04:46 PM
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Manitoba, Canada
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Quote:

Before affordable stroker kits mopar guys could..If I recall correctly buy a stroker crank or have a 440 crank welded/regound, use oem 440 rods and smogger off the shelf cast pistons in an RB block. This made 500 cubes. Heavy rotating assembly (compared to current stuff) and not recommended beyond 5500 RPM but a big torquer none the less. My question: Could a cheap stroker (reliable street only engine) be made now with a new stroker crank (under $400) and then oem rods and off the shelf cheap cast low compression 440 pistons?




Smogger 440 pistons have a higher compression height than your typical stroker piston for a 4.15" stroke crank. They'd be around .020 or so above deck. No problem there, just use a little bit thicker head gasket and you are good to go. Problem is they've got no valve reliefs so I don't think you could really run much of a cam. Yeah you can buy a jig to cut valve reliefs but by the time you've gone through all that BS you might as well have just dropped the $440 for a set of forged KB pistons for that stroker combo.

BTW, where do you get a stroker crank for under 400 bucks?

Re: Old school 500 cubic inch on the cheap? [Re: DaytonaTurbo] #208589
01/30/09 05:05 PM
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With a final balanced kit with H beam rods $1897!! why would you even think of trying to coble something together????? It's the new millennium Man!!!!
That said you can use this piston
400 - Comp / Dist - 1.817 (Set of 8)
We stock STD. / .030 over, all other sizes need to be special ordered
$303.95
SEA406AP
4.15 crank and stock 6.76 rods and be .070 down the hole and with a 86 cc head be at 9.8 to 1 compression about!!

Re: Old school 500 cubic inch on the cheap? [Re: 2boltmain] #208590
01/30/09 07:00 PM
01/30/09 07:00 PM

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We used to use a welded stroker crank, stock rods and 400 pistons.
All you would save now is maybe $100 by using cast 400 pistons. You'll be much better off using a new crank (for less than we used to pay to have them welded) and specific pistons with valve reliefs and the correct deck height. Nothing to be saved here.

Sheldon

Re: Old school 500 cubic inch on the cheap? #208591
01/30/09 08:28 PM
01/30/09 08:28 PM
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Its unreal the torture some people put themselves through !!!

Re: Old school 500 cubic inch on the cheap? [Re: 2boltmain] #208592
01/30/09 10:53 PM
01/30/09 10:53 PM
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Mr.Yuck Offline
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I priced out a few stroker options before I got my 440. Really it is hard to beat the pre-fab kits sold. It saves time and money. Oh and don't use either 484 or 509, their are much better grinds available today...easpecially if you're going to run 500 cubes.

Re: Old school 500 cubic inch on the cheap? [Re: Mr.Yuck] #208593
01/30/09 11:07 PM
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Streetwize Offline
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Actually the "on the Cheap" was to reuse your 400 pistons (Longer CH 440's won't work) and bore your 440 block to 4.342" (.022 over) and then (IIRC) use the 4.15 crank and the 440 LY rod and you get ~491 cubes.

You might need to check my math but I think that's right...at least it's feasible.

It'll be heavy and I think the slug still winds up down in the hole but the bottom end will lighter than a stock 440 and it'll be cheap (the cost of the crank and balancing).

I mocked one up that way with spare parts but I never built it...you'll be limited on cam lift due to no eyebrows inthe slug but if you want a low buck torque motor I'll bet a MP 528 solid would clear.

But I could see a very low buck "junkyard" torque motor turning high 11's or lower pretty easy.

Last edited by Streetwize; 01/30/09 11:23 PM.

WIZE

World's Quickest Diahatsu Rocky (??) 414" Stroker Small block Mopar Powered. 10.84 @ 123...and gettin' quicker!

https://www.youtube.com/watch?v=-mWzLma3YGI

In Car:

https://www.youtube.com/watch?v=PjXcf95e6v0
Re: Old school 500 cubic inch on the cheap? [Re: Streetwize] #208594
01/31/09 12:01 AM
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Quote:

Actually the "on the Cheap" was to reuse your 400 pistons (Longer CH 440's won't work) and bore your 440 block to 4.342" (.022 over) and then (IIRC) use the 4.15 crank and the 440 LY rod and you get ~491 cubes.

You might need to check my math but I think that's right...at least it's feasible.

It'll be heavy and I think the slug still winds up down in the hole but the bottom end will lighter than a stock 440 and it'll be cheap (the cost of the crank and balancing).

I mocked one up that way with spare parts but I never built it...you'll be limited on cam lift due to no eyebrows inthe slug but if you want a low buck torque motor I'll bet a MP 528 solid would clear.

But I could see a very low buck "junkyard" torque motor turning high 11's or lower pretty easy.




Again, even if it was doable, why would you not run the KB forged piston for the 4.15" stroke based 440's? Summit lists those pistons for $441.00. At least with those you can build a zero-deck quench engine or a domed piston build. Last time I checked, a new set of cast 400 or 440 pistons listed for $350. For the extra 90 dollars I think it's worth it to just get the proper pistons. Really, when doing a stroker build like that, the crank is the biggest expense.

Re: Old school 500 cubic inch on the cheap? [Re: DaytonaTurbo] #208595
01/31/09 01:35 AM
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The welded stock crank 4.15/LY/Ross piston combo is still alive and well in my Mirada. I did run the heavy 400 slugs for one year with home ported 906 heads. Ran low 11's with a MP .557 cam.

Same short block with Ross pistons, Stage VI heads, UD NF69 cam has gone a best of 10.04 @ 135.

Re: Old school 500 cubic inch on the cheap? [Re: RapidRobert] #208596
01/31/09 05:23 AM
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Quote:

I've been on this myself. definitely want cast pistons & I had checked out some 403 olds pistons. 4.351" bore/1.585 CH. they're on eGay for cheap. I'd prefer a B block & I'd have to fab an external oiling system. I haven't found the right combo yet




A couple of Q's here on the pistons .....

The 403 Olds ? ... did you use them bone-stock? .. no mods to the piston deck or pins ?

The KB's that were mentioned ... these are forged ? ...

Now on the top ring location vs top of piston ? .... what is the minimum spec? (no spray or boost)

Re: Old school 500 cubic inch on the cheap? [Re: dOc !] #208597
01/31/09 11:01 AM
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Quote:

The 403 Olds ? ... did you use them bone-stock? .. no mods to the piston deck or pins ?
The KB's that were mentioned ... these are forged ? ...
Now on the top ring location vs top of piston ? .... what is the minimum spec? (no spray or boost)


Nothing yet it's just on paper(& in my head ). I am a quench fanatic & I cant get it with all the combo's I dreamed up so using the olds piston my be out & they are a dished piston so I'd have to machine the outer perimeter down. the pins are .9804" another problem, then buy the cutter & notch for valve clearance but maybe not needed as I had plannd on a stock cam. Sometimes I thrive on misery & as mentioned this might be one of these occaisions but I cant see $1899 for a 440 source kit when I just want to throw together a BB for a daily driver 65 dart(hence the cast pistons) plus their kits MAY or may not need more work. I didn't catch the KB ones you mentioned but they are probably hypers & it'd be on their site to easily access. standard ring gap would be ~.004" per inch of bore dia(top ring) unless it's a KB hyper then maybe .0065" per inch but check their chart and .003" per inch of bore dia on the 2nd ring. EDIT oh you asked about location as in if you'd mill the tops? I dont know the ans on that.

Last edited by RapidRobert; 01/31/09 11:03 AM.

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Re: Old school 500 cubic inch on the cheap? [Re: RapidRobert] #208598
01/31/09 11:05 AM
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Quote:

Quote:

The 403 Olds ? ... did you use them bone-stock? .. no mods to the piston deck or pins ?
The KB's that were mentioned ... these are forged ? ...
Now on the top ring location vs top of piston ? .... what is the minimum spec? (no spray or boost)


Nothing yet it's just on paper(& in my head ). I am a quench fanatic & I cant get it with all the combo's I dreamed up so using the olds piston my be out & they are a dished piston so I'd have to machine the outer perimeter down. the pins are .9804" another problem, then buy the cutter & notch for valve clearance but maybe not needed as I had plannd on a stock cam. Sometimes I thrive on misery & as mentioned this might be one of these occaisions but I cant see $1899 for a 440 source kit when I just want to throw together a BB for a daily driver 65 dart(hence the cast pistons) plus their kits MAY or may not need more work. I didn't catch the KB ones you mentioned but they are probably hypers & it'd be on their site to easily access. standard ring gap would be ~.004" per inch of bore dia(top ring) unless it's a KB hyper then maybe .0065" per inch but check their chart and .003" per inch of bore dia on the 2nd ring.




that would be correct , it's going to cost MORE in time and money to make that combo work , if it's even possible , you'd be better off with a cast 400 piston .

check ebarf for hawksracing , he sells stroker cranks for 495ish , use stock rods and 400 pistons . but yes KB has a shelf piston that will be eaiser to work with I'm pretty sure in both forged , but definitely hyper .

Re: Old school 500 cubic inch on the cheap? [Re: RapidRobert] #208599
01/31/09 11:12 AM
01/31/09 11:12 AM
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Here's a thought...why not just build a 440? any year will work, bore it .060 That gives you what???? 453ish cubes??? Then call Summit and order a set of pistons for it. Not sure what heads you are going to use. I'd guess depending on the rest of your set-up, stall rear gear and such you could pick a cam. For street use those extra cubes will probably just blow the tires up. You can go old scholl and get a 400, use a 440 crank and chevy rods for a 451, those run good. The problem I see is there really is no "cheap" engine build. Especially when a machine shop is involved. Some body here uses this as their tag line and it is true
"cheap, fast or reliable" pick 2 because you can't have all 3".

Re: Old school 500 cubic inch on the cheap? [Re: JohnRR] #208600
01/31/09 11:23 AM
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Quote:


check ebarf for hawksracing , he sells stroker cranks for 495ish , use stock rods and 400 pistons


Thank you John, I will


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Re: Old school 500 cubic inch on the cheap? [Re: RapidRobert] #208601
01/31/09 11:36 AM
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buy a cheap crank, use kb251 pistons with open chamber heads; instant 87 octane 493.

Re: Old school 500 cubic inch on the cheap? [Re: lewtot184] #208602
01/31/09 12:04 PM
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Cast pistons ring pack won't last long with those piston speeds...thing will be leaking 25% in a month or so with a 4.150 arm in it

Re: Old school 500 cubic inch on the cheap? [Re: lewtot184] #208603
01/31/09 12:30 PM
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2boltmain Offline OP
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The idea was that with the re use of existing oem parts the only real major expense was the cost of the crank. Here is what I observed: New stroker crank $600. New KB smog pistons on ebay right now- $120 plus $30 shippping. Reuse existing rods. So thats $750 so far. Thats what I was looking at. Obviously if there is another grand in machining and what not its not feasible over a modern kit. Someone mentioned piston to valve clearance is an issue- I assume this is why the old Bouchillion kit recommended the mopar 484 cam. Anyway the thought was an econmical 500" motor with stamped steel rocker arms and a long duration hyd flat tappet cam. The traditional chevy grind cams for mopar dont have a lot of lift for their duration and PAW used to have their in house name brand cam/lifters for under $125.


Keep old mopars alive.
Re: Old school 500 cubic inch on the cheap? [Re: 2boltmain] #208604
01/31/09 12:59 PM
01/31/09 12:59 PM
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I used the Summit 488 in a stock 9:1 440 good cam. The 484 will bleed compression and you will need a 3000 stall and at least 3.91's. Summit cam kits were on sale a month or so ago for $62! w/ lifters.
Why not look around? somebody is probaly selling a used stroked short block you can get for 1/2 what it costs to build.

Re: Old school 500 cubic inch on the cheap? [Re: Mr.Yuck] #208605
01/31/09 01:59 PM
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There's some pretty good points made here, a well built lighter bobweight 440 with custom slugs might be a better bet overall. Pretty easy to run 11's with an old school 500 hp 440, even on pump gas. Plus if you build it with decent compression flat tops you can upgrade the heads to closed chamber E-heads/stealths or SR's later on and probably pick up another 40-50hp and 500-700 more RPM which would morethan close the gap on a stock cast heavy slug 490....

What body is it going in? depending on the weight and gearing sometimes it's a better overall fit (in terms of real world ET) to trade cubes for RPM. A dollar in the heads can be worth 3 in the short block. Most stroker guys do both but I can see certain apps where a freight train torque motor can be cheap and fun. A good example is a 500 caddy in a 78-88 GM A body, it's all done by 5000 rpm but man it's fun getting there.

Last edited by Streetwize; 01/31/09 01:59 PM.

WIZE

World's Quickest Diahatsu Rocky (??) 414" Stroker Small block Mopar Powered. 10.84 @ 123...and gettin' quicker!

https://www.youtube.com/watch?v=-mWzLma3YGI

In Car:

https://www.youtube.com/watch?v=PjXcf95e6v0
Re: Old school 500 cubic inch on the cheap? [Re: Streetwize] #208606
01/31/09 02:36 PM
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What about the old school 3/8s offset ground stock crank,chevy 7.1 rod,custom piston = approx 470 CI. No welding req and around 2375 bobweight. That was one of the old school combos built in the 90s by a local builder here in VA and may be cheap to build today IF you could still get the pistons and the crank work for a fair price. Its kinda hard to beat the price of avail kits these days.

Re: Old school 500 cubic inch on the cheap? [Re: THESHAKERPROJECT] #208607
01/31/09 03:54 PM
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I am not building this engine. It was just a thought. I have a 71 Demon in storage. I can tell you that when I was active in the car hobby I drove my car 5 months out of the year- under 1500 miles in that time. No strip time just fun street blasts, cruises and errands. Thats why a poor mans stroker is appealing to me. I read the smog pistons are perfectly fine for max 5,500RPM. The chevy grind cam- like a Comp Cams magnum 290 has a lift of only 501 but duration of around 245. Goal would not be to run 10s or 11s but a super torquey RELIABLE beast of a STREET ONLY engine. I live 40 minutes from Martin Dragway but even when I was driving a car I just never made it there. (Demon is in storage until 12 year old daughter turns 18 and some money is freed up)


Keep old mopars alive.
Re: Old school 500 cubic inch on the cheap? [Re: RobR] #208608
02/01/09 09:36 AM
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Quote:

Cast pistons ring pack won't last long with those piston speeds...thing will be leaking 25% in a month or so with a 4.150 arm in it




And the reason for this is ...?

Re: Old school 500 cubic inch on the cheap? [Re: dOc !] #208609
02/01/09 11:41 AM
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I remeber seeing a number of people selling stock cast 440/400 pistons on ebay for cheap. Been some time since I searched, but they were like $18-$20 each.

I looked into building a 400 block/440 cast crank stroker with oem cast 440 pistons. Wont achieve 500 cubes, but its probably the lowest $ stroker you could build. With cheap ebay pistons, and stock crank and rods, the biggest costs would be piston reworking (valve reliefs and cam clearance) and your general machine work and balancing.

Read here: http://www3.sympatico.ca/big-d/460.htm

I ended up with some 440s so I went that direction instead.


I used to care but....... things have changed
Re: Old school 500 cubic inch on the cheap? [Re: NTOLERANCE] #208610
02/01/09 01:42 PM
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There are reasons for everything... simply sticking misc part designed for stock stuff into a hole they will fit in is not always the best course of action. In the case of pistons... some numbers that might clarify.
stock 400 stroke (3.38"):
mean (average) piston speed at 4K= 2253feet per minute At 5500rpm= 3098FPM
Max piston speed at 4K= 3648FPM At 5500rpm= 5016FPM

4.15 stroke:
mean piston speed at 4K= 2756FPM at 5500= 3804FPM

Max piston speed at 4K= 4500FPM at 5500= 6200FPM

The reason cast pistons are not part of stroker kits is because they simply are not designed to withstand high acceleration and deceleration rates the longer strokes create. almost 25% more max speed, but accelerated and slowed down in the same distance. The pistons will simply flex for a while, then either the rings begin to lose seal as the ring lands deform, or the pin rips offf the domes. You can help the mean average speed by keeping the peak rpms down. But you can't drastically affect the rate of acceleration because of the stroke. So, you have a package that limits lift because of valve reliefs, and rpm due to materials. I understand the "do it because I think I can" mentality. But truthfully, I dont see why someone would want to unless you have a full machine shop to play in for free. Then it might be fun to see what could be done.


Well, art is art, isn't it? Still, on the other hand, water is water! And east is east and west is west and if you take cranberries and stew them like applesauce they taste much more like prunes than rhubarb does. Now, uh... Now you tell me what you know.
Re: Old school 500 cubic inch on the cheap? [Re: NTOLERANCE] #208611
02/01/09 01:58 PM
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Posts: 4,761
Holland MI Ottawa
Sometimes I like to ponder a possible buildup for my Demon. Not having spare money means a purchase here and there with parts put in storage till the day arrives it can all be put together. The new kits are the way to go and are a great value. 15 years ago the cost was more than double to do a stroker than it is now. The poor mans stroker is not cheaper if there is oddball overboring/machining required to the block and pistons. The interest to me is the concept of buying new $600 stroker crank - $135 new pistons, inspect parts and assemble. Comp Cams magnum 290 (244dur 501 lift) stamped steel rockers, new valve springs, Torker intake and big holley. Engine assembled with already owned parts and parts available used. Stock but sound OEM iron heads with the goal of stealth heads in the future.


Keep old mopars alive.
Re: Old school 500 cubic inch on the cheap? [Re: moper] #208612
02/01/09 02:08 PM
02/01/09 02:08 PM
Joined: Jan 2003
Posts: 9,870
Weddington, N.C.
Streetwize Offline
master
Streetwize  Offline
master

Joined: Jan 2003
Posts: 9,870
Weddington, N.C.
Good point about the piston speed, if I were doing a low buck torque motor I would open up the bores about 1/2 a thou (.0005) to compenstae for the extra heat generated from the higher than normal piston speeds and then cam/port the motor to limit the motor to about a 4800-5000RPM power peak with a redline of about 5300-5500rpm. I'd also shorten the factory pressed pins about 1/2 inch to save about 50 grams. A 400 piston is about 80-90Grams lighter than the 440 and the skirt and ring supports are roughly the same, in terms of bobweight my combo on paper comes out a good bit lighter than a 440 Magnum and lots of those got spun to 6200-6500. But remember (and a lot of people don't realize this) the cylinder pressure stresses actually drop off as the VE plummeted with the old heads that were already spent, even though the Frictional HP losses continue to move upward with RPM. All in, I think a low buck 490 built this way could safely operate to 5500, but again you want to 'build-in' your rev (piston speed) limiters to minimize the potential for sealing losses, and building to make sure the VE drops off like a rock at a moderate RPM is really a good way to do that. The motor will continue to accelerate but the RATE of Acceleration drops off because the pumping efficiency is spent. I can think of a lot of apps where a motor like this could be a lot of fun on the street....but Like Clint Eastwood says "you gotta know your limitations!"

Last edited by Streetwize; 02/01/09 02:11 PM.

WIZE

World's Quickest Diahatsu Rocky (??) 414" Stroker Small block Mopar Powered. 10.84 @ 123...and gettin' quicker!

https://www.youtube.com/watch?v=-mWzLma3YGI

In Car:

https://www.youtube.com/watch?v=PjXcf95e6v0
Re: Old school 500 cubic inch on the cheap? [Re: moper] #208613
02/01/09 02:36 PM
02/01/09 02:36 PM
Joined: Jul 2008
Posts: 30,424
Florida STAYcation
dOc ! Offline
The village idiot's idiot
dOc !  Offline
The village idiot's idiot

Joined: Jul 2008
Posts: 30,424
Florida STAYcation
Quote:




The pistons will simply flex for a while, then either the rings begin to lose seal as the ring lands deform, or the pin rips offf the domes.







I am no metallurgist .... but isn't a cast piston much less prone to "flex" than a forged piece ? ...... it is a harder and more "brittle" part than forged. The pin ripping off the dome IS a valid observation. But that concern could be limited by reducing the weight of the piston/pin combo.

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