Well I have posted recently about my engine buildup. i bought aggiez28's rotating assy and block. Here are the components again:

Cola 3.75 crank
Eagle H beam 5.7: rods
JE/SRP -31cc pistons
Oliver Billet Splayed 4 bolt mains
214/224 .565/.605 114LSA (I am buying that seperate)

My heads are currently running 55cc chambers according to my head porter. That puts me at around 9.0-9.1 to 1 compression. Is this bottom end gonna hold up to 15psi at that compression, and is it safe to run 15psi @ 9:1 anyway? I dont really want to take the dremel to the heads to pick up a few more cc's. Thanks in advance.

 

What kind of head unit will you be running to produce 15lbs of boost? I think you will not have a problem running 15lbs of boost with your setup. Just make sure the car is tuned properly and you may want to run a little race gas to be on the safe side when you go to the track.

 

Ah yes, you are my new friend I seem to be getting alot of answers form you lately It is an S Trim, so it may be only good for 12-14psi, I dunno. I will use the pullies to produce the 15psi, but it will actaully do is anyones guess. I do have an alky kit installed. I will be using 91% Isopropyl?? (rubbing alcohol). I'll have it come on at about 5psi.

 

I ran 17# of intercooled boost w/9.1:1 compression on pump gas. up to 27# on race gas, never hurt anything.

new motor is 9.33:1

 

What king of components did you use on the bottom end?

 

Based on our experience and many posts from other S trim owners, I would be surprised if your S trim made 12 lbs. boost. I'm thinking more like 8-9 lbs.

 

I thought Rich made close to 15psi with his 383? Anyone else have any experience out there?

 

TRW forged pistons, eagle h-beam rods, GM forged crank (355 c.i.)

It's all in the tune. ran a 6.17 @ 117 in the 1/8th. on around 19# boost.

 

He should be able to get a little more since he is not going to be running an intercooler. I am thinking 12-13 lbs.

 

ZBass28 has a similar setup to that, it's s 355ci with an S Trim pulleyed for 15psi.

I think that you can see 15psi but that is the max. The S Trim is rated for 625fwhp but it's been shown that they can in fact make up to 650rwhp but that might be a blower on kill that is being significantly overspun.

I think it will come down to your intercooling.

I would go 8.5:1 if have to order pistons anyway.

My Griffin FMIC has allowed me to make 746rwhp thru an unlocked T400 on what is basically 110leaded. That is thru a 9", 4.11's and 28" slicls. So that is the dyno queen equivalent of 825rwhp. That was with 17psi. I think I could make a dyno queen number of 700rwhp on pump gas but it might be on the edge, 675rwhp for sure.

 

A 383 SHOULD EAT UP A LITTLE OF THAT BOOST THOUGH SHOULDNT IT?

 

With a rigid intake I saw 14-15psi on my 383 with the S-trim. This was with mediocre heads and a small cam though (same cam - my "design"). With better heads it would likely make a bit less boost.

Rich Krause

 

On the intake side...like a Brad Brand tube? Are there cheaper alternatives to Brad brand? My heads flow 271/187 @ .550 lift (I dont have mid lifts on me), so they arent ground breakers either. They probably flow similar to your unported AFR heads.

 

Yes, I used Brad Brand's tube. I don't know of any cheaper alternatives unless you can fab up something yourself.

Flow numbers sound fairly similar, so if you have low intake restriction you should see decent boost with an S-trim An intercooler/aftercooler will eat up boost if you are using one (but should make more hp).

Rich

 

alky for me...