ok so I've been doing a lot of home work for the last 3 years (since i got the camaro) I am currently building my engine and here is what i have so far........

350 4-bolt main one piece rear main seal
eagle h-beam rods
GM Forged steal crank stock stroke
Keith black hyper pistons flat top
seal power file to fit rings
speed pro rod and main barings
melling high volume oil pump and moly drive shaft (pump shaft)


The plan is to run 8.5:1 compression and some after market aluminum heads with 74 cc chambers
probly roller valve train
and the Holley Stealth Ram intake and management system

the question is about my cam sellection

I want to build the motor and install it in my car this winter so i need to sellect a cam that will work well (I would like to see 300+ RWHP) on NA power...... The turbo kit will be the project for next winter..... so the goal is good na power and a good cam that will match a turbo aplication....

i know this is alot and there are a million posts on this topic but no one is planing this kind of build,, (that i have read) i pulled out all the stops on the bottom end when i decided to go to the turbo in the future.. so i fugured spend the money now or later when i break the stuff u know??? any insight would be excelent

 

Keith black "hyper" pistons flat top would work but are a bad choice for a forced induction engine. Go with a quality forged piston instead!

 

well i went with the hyperutectic pistons because they are equaly strong as the forged with minimum growth under heat.... there for when the engine is cold no piston slap and under heat good sealing... the kieth black pistons are a good quality piston by many standards... thanks for the input

 

Do more research then. you shouldn't be using a hyper piston.

 

just got off the phone with keithblack (the company) and talked to a couple of tech guys that are running the hyper piston.... one guy is running 16 psi and a 175 shot with hyperutectic pistons, ran 280 drag passes with out killing the pistons... im looking to run between 7-14 psi.... intercooled with an intercooler sprayer... the tech guy says that with the correct fuel and spark set up the piston will live.....

on another note if some one who knows the technical or scientific reason why a forged piston would be so much better... (not just because "Forged is the only way to go" then ill take a listen... im not trying to be a dick but Thats all i hear from people who arnt doing the same thing i am......... so sorry for the arguement but i would really like a more technical answer to why the pistons i chose are not good enough

 

I believe 83 Crossfire TA and someone else already explained it. Do a search for hyper AND "turbo". You can read the scientific part about it. If you really cared, then you would search.

Like the tech guy said.......correct fuel and spark........don't rattle it and all will be fine. Good enough is always a matter of opinion. If you are better than most at tuning then you can probably get away with cheaper parts.

As for the title you chose "......., it just takes money right?". Yeah, half true. A lot of times having the right info beats the need for money. Sometimes money wins and sometimes smarts beats money. Anyway, if you are smart about tuning it, then you probably won't need money for forged.

J

 

yup hypers are actually stronger than forged pistsons

but they are so rigid that detonation actualy shakes them apart, there's no give.

a forged piston can deform a bit if you run into detonation problems, and that extra give means the pistons don't shatter...as easily atleast.

I'm glad you were just off the phone with keith black, he told you there are lots of people running hypers in boost applications...yup there are, i'm going to be doing it myself. but if you are putting together a nice rotating assembly, why would you deal with the problems that hypers bring along with them.

you can't jump on people this quickly on the boards man. I suggested you did more research on the piston issue. I wasn't going to spoon feed you some pretty easily looked up information. Instead, you just got confirmation that other people use hypers in these applications...what's the point, use the best parts especially since they aren't very muhc more money. Its a safety margin that is very nice to have. I say this because its sounds like you have this engine planned, and not built. If it's already built, then run with it and err on the very safe side of the line.

 

im sorry for being short with every one i have just been getting alot of "subject matter experts" i didnt think of the Extra strong design as a bad thing.. now that u mention it a little give sounds like a good thing....... I have most of the parts purchased but i havent assembled the bottom end yet..

I just thought that the pistons would be strong enough and if the motor was properly tuned then detonation would not be an issue... ill look a little harder at the forged piston avenue before i finalize the assembly

 

Why would you buy pistons before heads anyway?

 

whats the difference if u have a goal in mind and a plan... i wanted to get 8.5:1 compression and an effective combustion chamber so i went with a flat top piston with 7cc valve reliefs witht the idea in mind that i would use a 72 cc head to acheive my compression ratio (with the proper head gasket and deck hight) the only research i need to do is on the matching of the intake and exhaust runner size compaired to my cam.... so in all i dont think it matters what u buy first. if i went i got some dome top pistons and thought i was gonna get the results i want after the fact then i would be stupid lol......

 

It doesn't matter what you buy first. The odds are that you might find a better deal on used heads vs. pistons. That would be the only reason for getting heads first. If you are going with new stuff then it doesn't matter.

The KBlack site has a good compression calculator. Your setup kind of sounds like mine in terms of compression. I have 7cc KB pistons, 4.030" bore, 76cc heads, .028" head gaskets, and the pistons sit in the hole about .028" (stock block-not decked). It yields about 8.6:1. Your static compression will be higher.
Your can check your dynamic compression also. I think mine comes about to about 7.8:1 with the cam I am using.

 

well i thought about what im doing and a 400 horse NA motor sounds like more fun, more reliable, and cheaper than the 600 horse motor i was wanting, i realize the KB pistons are a bad choice for the application and i am gonna save this idea in the old memory banks for another project down the road.,,,,,.... so im letting the compression go to 9.5:1 and matching the cam and heads, so i think i should be able to get400 out of it right??

 

How's this:
https://www.thirdgen.org/techbb2/sho...=hypereutectic

or this:
https://www.thirdgen.org/techbb2/sho...=hypereutectic

or do a search and you'll find dozens more.

 

i did all the reading u guys suggested and learned alot about the stuff im trying to do and here is my conclusion............



gonna build a screamin NA motor...... make around 400 horse NA power and sit on the turbo idea for another car..... may be getting a 96 fire bird that me and the old man are gonna make into a pourpose built race car..... dont know what were doing yet but forced induction might be in the cards for this one lol

so thanks for every thing and ill keep every one posted with the results of the motor build