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View Full Version : question about 502 for the gurus out here



StreetGliderX
07-02-2012, 04:33 PM
i have a 98 k3500 that is about 250k miles in and the motor is still goin strong,... but when it does go i want to research my options,.... what i want to know is can i order a 502 short block and have my heads worked and use them and my intake to make my old chevy a 502 beast? all while looking really stock as it sits in the frame rails? i realize some ecm tuning will be in order but that can be handled. i just really like this old truck and i hate to have to start over and buy a new truck,... i could do an engine cheaper than a new rig.

thanks in advance fellas

PonyKiller87
07-03-2012, 07:45 AM
Short answer is yes, it would all bolt up and yes it would make more power than the stock 454.

But, based on all of the info on here and other places, the stock heads are really going to hold back the engine. Its going to make a ton of low end power, but it will be just like the stocker where the power is all done at 4000-5000 rpm. If your going to do this I would look at some different heads to go with it.

Also if you were to do this, I would make sure you get the fuel injected version of the short block, I would imagine it would come with the reluctor wheel for the crank sensor and the proper balancer. Other wise you may have to have a little of the balancer snout milled off to make room for the reluctor wheel.

StreetGliderX
07-04-2012, 01:51 PM
well low end power is where i want it. my rig weighs in at 11,200 lbs loaded and its loaded 99.9% of the time. i rarely run over 3k rpms in my old rig and it has the 5spd nv4500 trans. good great gobs of stump pulling power is what i desire. thanks for the input. but if i did decide to change heads what do i need to look for and will i be able to bolt all my factory MPFI vortec intake and all my goodies on it? i dont mind going headers and also eliminating any emission crap as well

so Gm has a short block for the 502 designed for the fuel injected vehicles?

FordeatinZ71
07-04-2012, 02:08 PM
Lee! What's up bud? I think a 502 would make you a very happy customer...heck, with enough port work I think they'd flow fine on that 502. And boy would she pull a load!

PonyKiller87
07-05-2012, 08:44 AM
With the heads, I'm not sure what would be a good one for you, there are heads out there that would be a direct fit, just a matter of if they will make the power where you want it. Don't waste your money having the stock heads ported, there is a ton of stuff out there that shows that even with a ton of work the gains are very small on these heads.

GM does have a Ram Jet 454, 502 and 572 which come with all the fuel injection stuff, so they should have some type of crank sensor, and I would imagine you could get them as a short block only.

That brings up another point, if your looking at a 502, might as well look at the price jump to the 572.

Busted Knuckles
07-11-2012, 10:04 AM
As long as you're not revving over 4K,stockers will be fine. You might find someone to knock the swirl ramp down in the intake ports to help them flow a bit better.
Torque is king, so big ports ain't in the picture. I think a peanut port head will feed it and with a good valve job and a little bit of bowl work, they would probably be as good or better than the stock L29's.
It would be easier and cheaper to find a bare block and stroke it with a Scat cast crank. That's what I'm planning for my '98.

99urbansuburban
07-11-2012, 10:38 AM
As long as you're not revving over 4K,stockers will be fine. You might find someone to knock the swirl ramp down in the intake ports to help them flow a bit better.
Torque is king, so big ports ain't in the picture. I think a peanut port head will feed it and with a good valve job and a little bit of bowl work, they would probably be as good or better than the stock L29's.
It would be easier and cheaper to find a bare block and stroke it with a Scat cast crank. That's what I'm planning for my '98.

I thought l29 heads are the ovalports, not the peanutports. I could be wrong

Busted Knuckles
07-11-2012, 01:16 PM
I thought l29 heads are the ovalports, not the peanutports. I could be wrong

They are, but the vane in the intake restricts flow plus the vane part of the kidney shaped chamber does, too. You'll have better velocity with ample runner size with a peanut port head if all you're after is 4500 - 5000. You'll also have a better compression ratio, you'll be too high for towing with the L29 head and flat top pistons. Port match the peanut port heads to the Gen 6 intake and clean up the bowls and get a good valve job. As long as the runners are big enough to feed the engine at desired RPM's, the smaller runners will have higher port velocity and will do a superior job of filling the cylinders...plus it's more efficient since the fuel/air mixture is swirled more and mixed better.
You'll either move what you're hooked to or pull the hitch off of it.
My '98 is a 4WD with the big honkin' 4401 transfer case, low gear of 2.63:1. Combine that with a high torque stroker engine with peanut port heads and I will be able to tear some $hit up!!!

oldred93
07-11-2012, 01:46 PM
with the 502 you could do this :aniteef: http://www.youtube.com/watch?v=WCrgvxwFMLs

StreetGliderX
08-27-2012, 10:10 PM
Thanks fellas! She still kickin but I need to be exploring options!