Dyno 402 T76GTQ ### in
Originally Posted by NA$TY-TA
I dont doubt the GT42-76 w/ a T6 falnge will out flow that 76... i had one with a T6 flange and she was out of steam by 14 psi... im jost posting up my .02..... we will see as time goes along with the STS 76's on a 408....
Kyle
Kyle
I wasnt questioning whether your right aout the 76... just mentioning that rear versus front MIGHT not yield the same results. FYI... I sold my GT42 (same as yours) and will be going 88mm for my 383 LTx 
get a backpressure reading on that setup.
Also, has anyone ever heard of a a similar t76 with a t6 turbine housing? Worth a try, i guess, if your set with that turbo.
I agree though, the compression maps suggests that the turbo used for this app. is to small. A t88 with a t6 will be a good match. If anything, please get a backpressure reading so we can see what is happening infront of that turbo.
LAterZ!
Also, has anyone ever heard of a a similar t76 with a t6 turbine housing? Worth a try, i guess, if your set with that turbo.
I agree though, the compression maps suggests that the turbo used for this app. is to small. A t88 with a t6 will be a good match. If anything, please get a backpressure reading so we can see what is happening infront of that turbo.
LAterZ!
ok, now that i got your attention... what is the basic difference, in actual application and productivity (how it runs) a S82 compared to the S88?
That S76 seems like another good solid match for this app. as well. What AR's is it available in? Also, the S82, what ar's can you get tha turbo with?
That S76 seems like another good solid match for this app. as well. What AR's is it available in? Also, the S82, what ar's can you get tha turbo with?
The A/R's available are 1.1 and 1.3A/R's. The units are all based on the same chassis and will produce big power. As for 82 vs 88, well the 82 is a trimmed down wheel we do on the CNC machine. Its essentially an 88mm wheel CNC cut down.
Originally Posted by obZidian
......
That S76 seems like another good solid match for this app. as well. ....
That S76 seems like another good solid match for this app. as well. ....
Kyle already mentioned in this thread the ineffeciency of this unit on his 370.
I am going to do back preasure test this weekend before turbo and before and after intercooler. The thing is I had the opertunity to build a 402 for the same price as 370. What would you have done. I did what I wanted and built the 402. I won't have to turn the engine as hard with this setup to make the same power and more.
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Verdad Gallardo The cool thing is it makes sick low end power. Instant tire shreader. I am thinking of doing a 88 of some sort but not for sure yet. I will probally enjoy what I have for now. Also the funny thing is this is still on stock rear LOL. Early Spring I will order one for it. What plugs are you guys running?
Im running TR6's..... Yeah i might have done a 408.... depends on what parts are in it..... ill tel you one thing..... ill be going back to aluminum sooner or later...... this extra 90lbs on the nose is hurting me.....
If i ever do a 408 it will be with a 88/98 at least or a 94mm....
Have fun driving it.... thats what im doing to mine.... it loves these 40-55 degree days.
Kyle
If i ever do a 408 it will be with a 88/98 at least or a 94mm....
Have fun driving it.... thats what im doing to mine.... it loves these 40-55 degree days.
Kyle
Originally Posted by 02SSLE
I read in my GM performance book that there is only 30 pounds difference between the Alum and the iron.
hah ah ah ah LOL i guess they never took one and wieghed it.. LOL
ive had both...... 30lbs wont make the front sag like an iron block will..... the 1st time i got an iron block i had to get rid of my prokit springs.... she sat wayyy to low.....
i had the cmotorsports single kit with a t76 q trim on it running on a 408. it maxed out at exactly the same hp and tq. this was thru a 4l80e and tcase.
here is the exhaust manifold it had on it. along with a 3" dp
next we steped up to a "race" header and a 3.5" dp. here is a pic of that.
guess what. exact same dyno numbers. i would have thought the down pipe at least would have helped some but it didn't so to me that says the turbo itself was maxed and not the turbo set up.
last mod was to swap a pt88 with a t4 flange. it bolted right in place of the t76 on the hot side but i had to redo the cold side. wamo, 1000rwhp. i am sure the "race" header set up is better than the first set up i had but from those tests i dont think the first header was maxed out yet. it would have been neat to see what the 88 could have done on that first header and a tiny 3" dp. i bet it would still hit 900+rwhp
here is the exhaust manifold it had on it. along with a 3" dp
next we steped up to a "race" header and a 3.5" dp. here is a pic of that.
guess what. exact same dyno numbers. i would have thought the down pipe at least would have helped some but it didn't so to me that says the turbo itself was maxed and not the turbo set up.
last mod was to swap a pt88 with a t4 flange. it bolted right in place of the t76 on the hot side but i had to redo the cold side. wamo, 1000rwhp. i am sure the "race" header set up is better than the first set up i had but from those tests i dont think the first header was maxed out yet. it would have been neat to see what the 88 could have done on that first header and a tiny 3" dp. i bet it would still hit 900+rwhp
Originally Posted by DrTurbo
The S76 is T6 and has a big turbine side. Probably the highest flowing 76mm unit I know of.
Originally Posted by TURBO383WS6
ok, you guys have definately got me worried now. i've got a 9.1:1 compression 383 LT1 w/ a PT76GTS. am i going to run into the same problems w/ maxing this out? if so, is there another T4 flanged turbo that i can step up to and keep most of the same hot and cold side piping to remedy the situation? i haven't had a chance yet to really get on this car, but what little i have played with has been pretty impressive for the ultra safe tune that's in it.
ok, you guys have definately got me worried now. i've got a 9.1:1 compression 383 LT1 w/ a PT76GTS. am i going to run into the same problems w/ maxing this out? if so, is there another T4 flanged turbo that i can step up to and keep most of the same hot and cold side piping to remedy the situation? i haven't had a chance yet to really get on this car, but what little i have played with has been pretty impressive for the ultra safe tune that's in it.