t76 exhaust flange question
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single digit dreamer
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From: omaha ne
t76 exhaust flange question i am running a t76 on a prety much stock 6.0, going to put a built 409 in there before long.
right now i am looking into puting a bigger down pipe on the t76, if there was a bigger turbo that i could bolt on without too much work now would be a good time.
the t76 has a 4 bolt exhaust flange, will a t88 bolt to that flange? will any larger turbo bolt to that flange?
right now i am looking into puting a bigger down pipe on the t76, if there was a bigger turbo that i could bolt on without too much work now would be a good time.
the t76 has a 4 bolt exhaust flange, will a t88 bolt to that flange? will any larger turbo bolt to that flange?
i am pretty sure the T88 was a different flange.
i think the T76 is about the biggest you can get, maybe a T80 not sure though.
you could go to a Q trim if you havent already, but i dont think that little gain would be worth it.
id just cut and weld a new flange on it.
i think the T76 is about the biggest you can get, maybe a T80 not sure though.
you could go to a Q trim if you havent already, but i dont think that little gain would be worth it.
id just cut and weld a new flange on it.
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From: Austin, TX
Isn't the T76 just a T4 flange? Cant you get a "small frame" T88 which is a T4 exh. flange? ITS makes an 80mm dual ball bearing w/ a .96 or 1.32 (i think) AR. Jim (its the one INTIMD8 had on his single setup).
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From: Austin, TX
Here...off Precision's site on their 4-bolt T88: Comes with Pro Race Compressor Cover - 88mm 59 trim comp wheel, 77 trim race turbine wheel, .96 T4 housing with 4.5" V-band or 4" round flange.
91.5's and up have the 'race housing' listed on the site. Probably the thumper stuff.
91.5's and up have the 'race housing' listed on the site. Probably the thumper stuff.
The the small frame 88 is a T4 flange. Also the ITS 80mm is a T4 also. The 91.5's and up are T6 flange. I have a small frame T88 on my SS, which is a T4 flange header.
Jose
Jose
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single digit dreamer
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From: omaha ne
i have a t76 qtrim .96ar now, it works great but i think with a low compresion 409 and free flowing heads it wont keep up very well. i am flatlineing the maf(60lb/min) right now at around 5200rpm so probably 65+lb/min. i haven't even turned it up yet 
i am not really sure what you guys are saying. i didn't know there were 2 diferent t88 turbo's either.
would a small frame t88 kick *** or is not much better than what i have now?
i am not really sure what you guys are saying. i didn't know there were 2 diferent t88 turbo's either.
would a small frame t88 kick *** or is not much better than what i have now?
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A small frame T88 would do much better then what you have now, but a T6 flange version would do even better, the only problem is the shear size of the big frame units. Typically they will require moving the radiator forward to allow for fitting. A small frame will bolt up though to your exsisting T4 flange header, and won't require much more room then your T76. I have a picture of all the different frame sizes for comparison.
The turbo from left to right are
T94 large frame TV style flange
GT47-88T Large frame
PTE-88, some call it a mid frame, but its a small frame. Basically same compressor cover of a T76, but much larger exhaust housing.
PT-67GTQ
Jose
The turbo from left to right are
T94 large frame TV style flange
GT47-88T Large frame
PTE-88, some call it a mid frame, but its a small frame. Basically same compressor cover of a T76, but much larger exhaust housing.
PT-67GTQ
Jose
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Verdad Gallardo Oh here is a new turbo (SST-72BB) we recieved yesterday. Its a T4 flange on the exhaust side, but Y2K compressor cover side, but they make a 88mm version that uses a T6 flange. This unit will be tested on our Supra. And hopefully I will be replacing the PTE-88 unit with a Y2K-88BB in the SS soon.
BTW, the turbo its beside is the big Greddy T88-H. Its the largest Greddy unit available, so it at least gives you a good size comparison. And the Greddy is a little larger then a PTE-76 dimensionally.
Also I will post some of the exhaust side next week. I will be at the F-body gathering 8 in Atlanta all weekend. But come tuesday I will have the pics taken and online for comparison.
Jose
BTW, the turbo its beside is the big Greddy T88-H. Its the largest Greddy unit available, so it at least gives you a good size comparison. And the Greddy is a little larger then a PTE-76 dimensionally.
Also I will post some of the exhaust side next week. I will be at the F-body gathering 8 in Atlanta all weekend. But come tuesday I will have the pics taken and online for comparison.
Jose
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single digit dreamer
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From: omaha ne
thanks for all the pic's, this is helping alot. looks to me like the pte88 is my best bet if i want it to not be a major project.
here is a pic of what i have now, can you tell me just by looking what fitmit issues i would need to work thru? if the exhaust flange is the same i should be able to bolt it to the header, i plan on a making a big downpipe and geting that ac out of the way. that leaves the air filter and intake piping, just looking at the pic of that pte88 it looks like the airfilter intake might be in the same spot. that just leaves the intake piping.
is the output on the pte88 bigger than the t76?
here is a pic of what i have now, can you tell me just by looking what fitmit issues i would need to work thru? if the exhaust flange is the same i should be able to bolt it to the header, i plan on a making a big downpipe and geting that ac out of the way. that leaves the air filter and intake piping, just looking at the pic of that pte88 it looks like the airfilter intake might be in the same spot. that just leaves the intake piping.
is the output on the pte88 bigger than the t76?
The PTE -88 will physically bolt up to where a T76 is. The only real difference will be the exhaust housing. I can already tell that it will be a tight fit on the exhaust side and will be close to the water tank next to the exhaust housing, but that maybe a result of the angle in which you took the picture. The 88 can be had in 2 different forms on the exhaust side. One is a 4 bolt donut flange, which uses a 3" downpipe, the other is the same housing, only its been casted to use a V-band and its a 4" downpipe. For tight spots the 3" donut flange version works the best.
As far as output, I'm not sure if your meaning physical size of the downpipe, if you are I just answered that part above. If you mean HP, then yeah the 88 will spank the 76, and its much more efficient at mid boost levels. I also have the compressor maps for both turbo in the link below under T4's. And you can see the 88 works best with the big cube, low PR motors.
Compressor maps
Jose
As far as output, I'm not sure if your meaning physical size of the downpipe, if you are I just answered that part above. If you mean HP, then yeah the 88 will spank the 76, and its much more efficient at mid boost levels. I also have the compressor maps for both turbo in the link below under T4's. And you can see the 88 works best with the big cube, low PR motors.
Compressor maps
Jose
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single digit dreamer
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From: omaha ne
that map for the 88 is sweet, i think i would be right in the 80% area with with i have now. things are going to go down hill fast with a free flowing motor and a 76, i could see 15psi and 80+lb of air, that is almost off the chart on the 76. still near 80% for the 88
by output i was talking about the size of the output pipe, i think the 76 is 2.5", looks like the 88 is 3" but hard to tell from the pic's. there is some room to weld on a fater intake pipe on the intercooler so that would be a prety easy fix.
i think the angle is throwing you off on the water tank
by output i was talking about the size of the output pipe, i think the 76 is 2.5", looks like the 88 is 3" but hard to tell from the pic's. there is some room to weld on a fater intake pipe on the intercooler so that would be a prety easy fix.
i think the angle is throwing you off on the water tank
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Why not keep the smaller inch motor and run a 76-GTS? I have my setup almost finished for my mustang (4.1" bore, 3.4" stroke, 360 inches) along with a PT76-GTS and an AEM, and I know it's going to make some sick numbers. Just waiting for the new rims/tire/axles and it'll be ready for the track, but I have been driving it on the street. I've seen this turbo make 900+ to the pavement on other cars, and a lot less lag than the T88.
Last edited by eviltwins; May 28, 2004 at 05:37 PM.
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Originally Posted by parish8
900 isn't going to get it done 
, with the 76 on a 6.0 i have prety much no lag. i think a 409 with a t88 wont be bad either, am i wrong about that?
, with the 76 on a 6.0 i have prety much no lag. i think a 409 with a t88 wont be bad either, am i wrong about that? Thread Starter
single digit dreamer
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From: omaha ne
i am no turbo expert but looking at the charts i can see where the t76 is at about 60% efficency and the t88 will be at 80% efficency(figuring 1bar and 80lb/min). i assume there would be some power to be gained there.
