My Car is on the DYNO right now. So far...

robh said:
Why are they worried about burning straps when it never opens? Next time he does a pull put your hand on it and let us know if it opens. You can't tell someone that is running a similiar turbo to Raj's turbo that he is done at 14lbs and 200 plus horsepower less.
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I thought Raj was running a GT42 or something similar. A t76 isn;t half the turbo a gt42 anything is. Secondly HP isn't nearly as important as AVG TQ under the Cruve which this mustang has tons of. Go look at the dyno sheet.
 
Rob, the gt4276 and a t-76 are about 250 hp diffrence, they are nothing alike other than inlet mm. Completly diffrent generation of turbo. the gt7642 flows as much air as the t88 . When it was strapped down the first time , the strap was about 5 inches from the wastegate outlet. I saw that and someone else moved the strap just in case it did open.

I was about 3 feet avay on 5 or so runs and was asked to see if the wastegate opened.
 
TRBOBUICK said:
Rob, the gt4276 and a t-76 are about 250 hp diffrence, they are nothing alike other than inlet mm. Completly diffrent generation of turbo. the gt7642 flows as much air as the t88 . When it was strapped down the first time , the strap was about 5 inches from the wastegate outlet. I saw that and someone else moved the strap just in case it did open.

I was about 3 feet avay on 5 or so runs and was asked to see if the wastegate opened.
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No standing around at cars...if you are there, you just might be put to work! :)

I should strap mine down for a few pulls just to see what numbers it says and see if they correlate to my trap speeds.
 
This is off precision's website

PT-76 1100HP 3.020" 4.030" 56 4" / 3" 360 Race Tan .81 or .96 GT-S 3.200" 2.960" 85

GT-42 1100hp 94mm, 102mm 53, 56 0.60 Standard 82mm 84 1.15

Guys don't get me wrong I don't care about horsepower numbers on the dyno or boost numbers but in real road testing I can't believe he is max out at 14. I would believe that exhaust backpressure at 2:1 would open that 10lb spring enough to bleed boost. But before I started ordering turbos I would try the $20 springs no matter what...
 
robh said:
This is off precision's website

PT-76 1100HP 3.020" 4.030" 56 4" / 3" 360 Race Tan .81 or .96 GT-S 3.200" 2.960" 85

GT-42 1100hp 94mm, 102mm 53, 56 0.60 Standard 82mm 84 1.15

Guys don't get me wrong I don't care about horsepower numbers on the dyno or boost numbers but in real road testing I can't believe he is max out at 14. I would believe that exhaust backpressure at 2:1 would open that 10lb spring enough to bleed boost. But before I started ordering turbos I would try the $20 springs no matter what...
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Its not a precision pt76 its a Turbonetics 76.
 
robh said:
Off of turbonetics website

6.0L T-76 .96 A/R 1000 HP

I'll be curious what he traps...
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The turbo only flow 90lbs minute. thats 1152cfm. thats not enough CFM to make 1000hp.
 
Sean said:
HP / 0.257 / cylinders = required airflow
we are shooting for 750hp

750/ 0.257 = 2918 cfm but that is going to depend on the TQ peak and peak rp, for hp.

HP formula is TQ x RPM / 5250 + HP

In the case of Dans car we have 632lb ft x 6200 RPM = 746hp.

.
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Sean,
where did you get the 6200 in this equation?

wasn't it 635 x 4300 / 5252 = 520?
 
Guys, you have to remember, it's not just the total amount of airflow the unit is rated at, it also matters where the turbo is at on the map.

The turbo I ran was a GT42-76, much stronger turbo than an old school t-76. If you look at the map, that 4276 would actually have been much happier on a smaller motor....which is why Brian is such a cocky mofo about his car lol...that turbo will make more power on a smaller motor than it did on my car.

The T76 is the same way. It might make 1000hp on a supra, but I don't know if it will make that much on Dan's car. I know it sounds fucked up, but that's part of the turbo learning curve. Who knows, it might even make 1000 on a real shitty 302, but not on Dan's bad ass "302".

Here's a real word example: Take that GT42-76 I ran last year. 3200# Mustang, kind of a shitty 347 cubic inch motor with faggoty cylinder heads that won't rev past 6000rpm. 155mph @ 3200#.

Take that same turbo (exact same A/R and everything) and put it on a bad ass built 370cid LS1 with nice heads that revs to 7000rpm. My buddy's did that. The car was a slug bitch. The turbo made boost, but the car was a turd, ran like mid 10's. Take that overworked 4276 off, bolt on an S88, and that same car goes like 150mph on the limiter at 1000ft. That car will probably exceed 158mph now that it has the proper turbo on it.

If you look at the map, the data tells you the reason. If you take the airflow consumption of a each motor at the given boost level, and see where it is on the map, it's happy on my car, not very happy on the superior motor. That T76, on the map that I looked at, will not be happy on Dan's motor. Just my never very humble opinion.
 
Fryguy302 said:
Guys, you have to remember, it's not just the total amount of airflow the unit is rated at, it also matters where the turbo is at on the map.

The turbo I ran was a GT42-76, much stronger turbo than an old school t-76. If you look at the map, that 4276 would actually have been much happier on a smaller motor....which is why Brian is such a cocky mofo about his car lol...that turbo will make more power on a smaller motor than it did on my car.

The T76 is the same way. It might make 1000hp on a supra, but I don't know if it will make that much on Dan's car. I know it sounds fucked up, but that's part of the turbo learning curve. Who knows, it might even make 1000 on a real shitty 302, but not on Dan's bad ass "302".

Here's a real word example: Take that GT42-76 I ran last year. 3200# Mustang, kind of a shitty 347 cubic inch motor with faggoty cylinder heads that won't rev past 6000rpm. 155mph @ 3200#.

Take that same turbo (exact same A/R and everything) and put it on a bad ass built 370cid LS1 with nice heads that revs to 7000rpm. My buddy's did that. The car was a slug bitch. The turbo made boost, but the car was a turd, ran like mid 10's. Take that overworked 4276 off, bolt on an S88, and that same car goes like 150mph on the limiter at 1000ft. That car will probably exceed 158mph now that it has the proper turbo on it.

If you look at the map, the data tells you the reason. If you take the airflow consumption of a each motor at the given boost level, and see where it is on the map, it's happy on my car, not very happy on the superior motor. That T76, on the map that I looked at, will not be happy on Dan's motor. Just my never very humble opinion.
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I fear that I over-built the motor for this turbo... combine the 4.125bore, 348ci with a set of really good flowing cylinder heads, and this thing wants more air...

I'm going to try the $20.00 18lb. spring that Rob is recommending, but if that doesn't work, then I'm going to begin looking for a great deal on a larger turbo... Anyone want to buy a virtually brand new, polished TurboneticsT-76?:icon_mrgr

Dan
 
I would rather upgrade a turbo then an engine. At least you already have the supporting hardware for a bigger turbo.

So ya gonna give me a shot at her while I have a chance :D
 
91trunk said:
I would rather upgrade a turbo then an engine. At least you already have the supporting hardware for a bigger turbo.

So ya gonna give me a shot at her while I have a chance :D
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You know that I'll be glad to:icon_mrgr Before I romp on it any more, I definately need to adjust these rockers. A few of them are clankin' around worse than a solid roller cam. I should get this finished up tomorrow sometime. I'll give you a call when I'm ready then we can go have some fun:peelout:

Dan
 
Listen to Raj he loves statistics.....and is right. However, Dyno's and turbo's don't mix. Take the car to the track. Dyno's don't load turbo cars right and in my opinion your car's tune-up will be a little off and will make more than 600hp.

I bet it spoils instantly:peelout:
 
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