My LT1 is ready to come out for a forged 355 rebuild. I've bought a 6-8 PSI nonintercooled kit. The cam I've got for it is a 224/230 XE. The heads will be mildly ported. My question is, what compression should I set this thing up for? Also what head gaskets should I go with? Emissions are not a concern if, if that matters. A compression change comes by way of piston selection, correct? Or is there something else involved?

 

Congrats on the purchase. You will be fine with compression anywhere between 8:1-9:1. Since you are staying with the shorter stroke of the 350 finding a pistons for that low of compression will not be a problem. With 8lbs of boost you don't need to have it O-ringed and copper gaskets, just a good quality gasket will keep it sealed.

 

Thanks 1994B4C. Any sugestions on what brand of pistons to look at or others I should stay away from.
I've been N2O and I'm pretty pumped about changing to the boost.

 

I would get a 2618 forged piston. There are several quality piston companies, Ross, Venolia, Probe, JE, etc...I personally bought Ross for the car I am trying to sell now.

 

In my 357 I am running JE's 9:6.1 on around 15 psi pushed by a t-trim. So far so good.
Scott

 

I went for a JE 8:1 as I consistantly move to places that sell terrible fuel (colorado 91). JE is a good name with a good price.

 

what kinda of blower is it? I ASSUME an s-trim (juding by the way you worded it). if you plan to only run "6-8psi" I would keep the compression up around 10:1.

If you are going to run more boost(which you should) say around 12-13psi, run between 9:1 and 9.5:1

 

You should do fine with the Fel-Pro #1074, which is the gasket most people are using. Held up fine on mine with 17psi of boost plus some nitrous. I am going to try the Cometics this year, but the extra $$$ is clearly not warranted for what you have in mind.

As Jordan said, CR and boost are related as is the cam. Also, you need to take into account the fuel you plan to use. I hope you aren't disappointed. 6-8psi on an LT1 with mildly worked heads may not be as fast as you want. If you are building a stout shortblock, I would say go for lower CR and more boost. What blower is it?

There are other good pistons out there for sure. But I would like to put in a vote for JE. Their "Extreme Duty" blower piston is a nice piece, though a little on the heavy side.

Rich Krause

 

Thanks for the info guys. It's a paxton kit that I bought from one of the guys on this board. Yes, I'm aware of the problems that can go along with the GSS style. If it fails I'll swap it for a newer gear driven style. So for a street set-up, can I leave the CR at stock with the cam I intend to use? If that's the case then it makes things a whole lot simpler. I was just concerned with how the cam might affect things in this set-up. I have 93 octane available just around the corner from me, which I run only anyway.

 

you will make more power with lower CR and more boost than you will with higher CR and less boost. If your not into making a ton of boost, I'd do what Jordan suggests.

 

JUst my 2 cents but sell the Paxton and get a ATI or a Vortech. That paxton won't last long.