KS91Z28

my engine has too many miles on it for a supercharger. I had it on the Dyno tonight and the best it could do was 284hp at 8psi boost. I think it actually made the engine worse. I have a ton of blowby, (which is 10 times worse now). The question is now what do I do? I could rebuild the engine back to stock for probably around $1,000 or I could buy a crate engine for around $2,100. I want the bottom end to be tough enough to handle whatever I throw at it in the future. I need your guy's advice.

NTChrist

ZZ4! Forged bottom end!
Except for those iffy hyper pistons...
Of course, there are a lot of 4th gens running boost/nitrous with hypers.
If you're not going too radical, I'd go ZZ4 shortblock, and probably be able to swap a lot of your current parts over to save some money.

89ProchargedROC

just freshen your stock motor

take it apart and re-ring it and throw in some cheap TRW pistons

TheWraith

i second that. If you're on a budget you can't beat that.

zz4 or a crate motor is not worth the money.

KS91Z28

Will the TRW pistons hold up to a little abuse?
I figured while I have it apart, I'll put in a fresh cam and lifters, oil pump and have the heads reworked.
I also thought about getting a new set of injectors. Would you guys recommend going through the dealer and getting the stock ones, or is there something or somebody better that you guys would recommend?
BTW, I really appreciate your guy's advice. :hail:

89ProchargedROC

Well i was very tired when i posted that last night

YES TRW's will hold up to a ton of abuse, i know people who are funning in the 9s on them

But the problem is that they only make them in .030 overbore and not stock bore size i believe

so you would have to bore your motor over

also TRW doesn't make the pistons anymore, you have to buy them through Speedpro

KS91Z28

So I guess I'll just have to wait and see how bad of shape the cylinders are in and go from there. If I don't need to bore it, what are some good pistons to put in at the stock size?

89ProchargedROC

believe it or not you could use some keith black hyperutectics and dont boost the crap out of them until you are ready to step up to a better piston

they are pretty cheap

KS91Z28

I plan on boosting the crap out of this thing later on down the road, (within reason), so I'd actually rather buy what I need right now so the engine will be ready for whatever I throw at it. Aren't forged pistons supposed to be good for boost applications?

TTA850

Yeah forged pistons are the best for boosted applications,but they are not cheap.I paid over $700 for the custom JE Pistons designed for 30 pounds of boost in my V6,and you need 8

The only thing I can tell you is get a good set of forged pistons,stay away from the Keith Black hyper-whatever pistons as they are more suited for mild n/a motors.

Steve

KS91Z28

I don't think I'll ever go up to 30 pounds of boost.

How about rings, cam and lifters?
Is there a certain type of ring I should get?
Would there be anything wrong with going back with a Crane cam? Should I stick with the stock specs on the cam?

B4Ctom1

the TRW 350 lower compression forged piston is one of the cheapest performance pistons anywhere.

PETE

iTrader: (1)

if you know anyone at a gm dealership you can possibly get a replacement crank that comes in their 383 crate it is a cast steel crank with a 3.80 stroke should hold up to the abuse you intend.you can use hyper pistons and get some longevity out of them but keep in mind tuning is everything.one big detonation is all it takes,but if you go on the safe side with boost and octane you'll do fine..030 over 350 with that crank should give you around 388.i've heard that these stump pullers are seriously mean pulling somewhere around 450 lb/ft when modded and about 375hp with only a mild cleanup on heads and a better cam than that rv/truck crap that they throw in it.
good luck

Pete89Z

Now wouldn't stroking a motor increase the compression, and increasing the compression increase the chance of detonation? Keep in mind that if you boost your engine you want to keep the compression down or even lower it. Just be sure to do research about the subject and it wouldn't hurt to buy a book on the subject.

poncho9789

Stroking the engine won't raise or lower the compression of the engine that is deterimined by the piston cc and heigth from the piston to the block deck,combustion chamber cc, and head gasket thickness combination you choose. I am also shure that he knows he needs to keep the compression down on his engine.

I would get a new gm forged steel gm crank good rods (powdered metal with arp wavelock bolts) and low compression trw forged pistons that would give you a good setup to run as much boost as you want to (within reason). Speed pro pistons are made by federal mogul and not over priced but not anywere near the cheepness of the old trw if they haven't raised their prices. If you want a bullet proof bottom end you will have to pay for it. You might also check into the summit forged cranks, PAW forged steel cranks and the eagle cranks they are cheep for what you get.