yelo04goat

iTrader: (11)

now that everything is starting to smooth out with the build and parts are going together. i need to figure out what size DP i "need"

the turbo has a 4'' dp outlet but a 4'' pipe is going to be hard to fit on a gto and will have to take some "clearance" of the frame rail to get to fit..

i would like to run a 4'' to a cutout in then down to a 3.5 or 3'' out the back

but if a 3.5 is all i can fit past the frame rail will i really be leaving tons on the table.?

should i say f' it and make the 4'' fit? then go to a 3.5 after a cut out to the back and through a muffler



the turbine is a 75mm f1 turbine



thanks guys

LT1RAY

iTrader: (21)

It has a 3" v-band exit for the exhaust.

yelo04goat

iTrader: (11)

It deffently does not sir. This is the bigger mid frame turbo not the tc unit

It is a 4"

Tally TransAm

iTrader: (17)

just finished a t4 s480 setup with a 4" DP and cutout going to 3" slp dual/dual. cutout was worth about 75 hp in the 13# range.

yelo04goat

iTrader: (11)

awesome i plan on goin to a nice s480 one day with this set up and a bit more boost then that

how is it with the cut out close though still make good power for driving and stuff ?

LS1NOVA

iTrader: (12)

You sure? 4" ID? GTO downpipes are a bastard, I think you'll be fine with a 3.5 or go oval.

yelo04goat

iTrader: (11)

yup im sure.. have measured it myself and this is pulled from tnetics site

Sharing a bearing system similar to the Y2K series, Mid frame units ensures extreme durability and robust performance. 4” V-band discharge standard. HP-series 72mm, 76mm and 82mm compressor wheels are available for Mid frame units.


its hard to believe noone uses or knows much about these but the pt 7875 is very popular this is a larger unit though

Tally TransAm

iTrader: (17)

heres a couple graphs for comparison

cutout open



through exhaust



drives incredibly quiet and still makes great power through the exhaust, but i definitely prefer it through the cutout. nice to have the option. I would be running the biggest exhaust possible on yours

yelo04goat

iTrader: (11)

yea i want to make the 4'' fit till the cutout then once its fully under the car go down to the 3.5 just so it still makes good power. but keep it quite for the cops and neighbors and for those guys that think they are just about to race another over weight under powered GTO

Ping King

iTrader: (20)

What are you power goals? Is 4" really needed? Is the wastegate dumped?

SPRAYED 01

iTrader: (22)

you don't need a 4 inch dp. Its only a 75mm turbine which is less then 4inch. A 3.5 will be totally fine. Guys running the precision gts 76 run 3 inch dp.

yelo04goat

iTrader: (11)

power goals are whatever it will make on pump gas and meth.. isnt the biggest dp you can fit the best? and i think i remember somewhere that going over 100% the size of the turbine helps? is this not true..

im sure it would still make great power on a 3.5 dp but wouldnt it make more with a bigger one and i mean it does have a 4'' on the housing

i guess im just trying to justify making room for it the way i want

LS1NOVA

iTrader: (12)

Since its a true 4" outlet, do the 4" downpipe for sure!!

yelo04goat

iTrader: (11)

since i know you have done a few any pointers on getting it to fit.. i know a 3.5 will fit down around the streering shaft so notch the rail a bit to make a 4 go in?

LS1NOVA

iTrader: (12)

Yep, Id notch the frame and do whatever it takes or move the radiator way up and mount side facing in the front with downpipe out where the ac compressor sits. Not sure if your keeping ac or not.

yelo04goat

iTrader: (11)

plan to keep the ac turbo is goin to sit where the airbox was. went to the 05/06 cooling system with som derale fans to save some roon and get rid of the big over flow tank ecu will either sit up on top of the fender or bring it in under the dash frame rail it is small notch and reinforcement of course plane to pt the cutout right behind the steering shaft and single 3.5 inch exhaust all the way back to the factory 04 bumper with a nice silent muffler in there some where

LT1RAY

iTrader: (21)

I have one on my car and it definitely is. The TC unit does not come with the 75mm exducer on the exhaust wheel. The Huron Speed kit uses a 3" downpipe as well.

Maybe this will help?
http://www.clampco.com/techspec/how%...s%20v-band.asp

yelo04goat

iTrader: (11)

I'm not going to argue what turbo I have.

My turbo does in fact have a 4" dp and even though Huron speed does offer a mid frame kit most the kits they put out are with the smaller tc t series super t turbos

This is closer to a s400 size or t6 turbo.

But thanks

LT1RAY

iTrader: (21)

I'm not argueing, I just thought you had the new version with the F1-75 wheel.

LosLs1's

iTrader: (21)

The mid frame does is for a 4" down pipe. I have a Tnetics mid frame my self and they are big campared to the T-series turbos