Which turbo? Forged 347
T76 does not spool as fast as the TC76 but will make a bit more power.
ST80 will spool almost the same as the T76 and make more power.
The Garret GT47 you talked about is a nice turbo (high priced) but i think you can get more from an ST80, also the ST80 will spool faster.
Also IMO a 9:1CR is close to the supercharger area, i would have done something near a 8.5:1 just IMO.
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I am guessing you are using thick deck heads? What brand are you using because you do not want them lifting or pushing water.
I know the TPS guys have a Twin Turbo F-body @ 18# and the heads have not lifted. Yettttttt......... They are running there 7.0x heads 280cc.
Whats the compleat break down of your engine, car, and what you are trying to do.
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They also have various A/R's for them as well. People have made 1100+ hp on a single unit. I'm buying either two of these or two of the 87mm's they make, heard nothing but good things about these turbos and for the price you can't beat them.
Outflows a few similar size units like the comparable GT garrets.
My car does take time to spool, would be curious as to how other folks' similar setup spools.
I'd say that the car feels like mid to high 9's at 15 psi right now on pump gas which is pretty cool.








