BlackNiteWS6

iTrader: (2)

Which head unit starts to make boost sooner the D1SC or the F1? I think ATI told me the F1 makes more boost at the same given rpm but they didn't really say were the F1 starts to make noticeable boost.
Thanks,
Den

MelloYellow

Unrelated to the Procharger, but upgrading from a Vortech S-Trim to T-Trim I had no loss in boost at lower rpm's. Started making power at same rpm and had more boost in mid-range and upper-rpms.

Ponyhntr

iTrader: (9)

At the same engine rpm and pulley sizes, the F1 will make more boost than the D1SC. The F1 has a more aggressive impeller and also has a 5.0:1 step-up compared to the D1SC's 4.10:1. That means the impeller would be spinning faster in the F1 with the same pulley ratio and engine rpm.

mdhmi

iTrader: (1)

The D1SC will spool at a lower RPM than an F1.

Mark

BlackNiteWS6

iTrader: (2)

After i wrote this post i did a search for pics of the F1. It looks like the F1's impeller blades are alittle more spaced out than the D1SC. That could be why the F1 takes alittle more rpm to make a good amount of boost. I guess they designed the D1SC to be a more street unit than the F series. The F1's impeller looks very close to a F1r. And i know that blower takes alot of rpm to make boost. I guess the F1 is more for upper mid range and top end. I guess the only real issue is the twin baby intercoolers. ATI made a set of new twin intercoolers that are 33% bigger than ours, but they haven't R&D'd them on an f-body yet. If they fit our cars they could be an alternative than installing a FMIC. Thanks for the info.

Slowhawk

iTrader: (12)

Also remember that if the blower spools earlier there is a chance you will get too much boost at redline.

BlackNiteWS6

iTrader: (2)

Slowhawk,
Yeah i hear ya...Well i plan on spinning the hell out of the blower so it makes alot of lower mid-range and top end boost by using a SD-Concepts setup and bleed of anything over 14 psi with an adjustable BOV. Either the ATI race BOV or the Tial unit is what i'm looking at. Or maybe even a Innovative unit. I'm not too concerned about making tons of boost now since i decided on a MTI 427 instead of a 383cid stroker. I really love the new GT76R turbo setup from LS1Speed, but the sick amount of torque it makes will destroy my trans and even a 12 bolt

Ponyhntr

iTrader: (9)

You can't do that with the ATI unit-maybe the others, but not the ATI. It's not a wastegate, just a by-pass valve. It's open under vacuum, then it shuts under boost-it won't open back up until it sees vacuum again. Just thought I would let you know.