New Project 408 and GT 42 76 Turbo Rear Mount
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When we first put my setup together we had some big back pressure issue's.
We were only running one 46mm wastegate
So we added another 46mm wastegate and It fixed it.
So we are putting 2 36mm wastegate's on this setup, and we are hoping that will take care of this issue
We were only running one 46mm wastegate
So we added another 46mm wastegate and It fixed it.
So we are putting 2 36mm wastegate's on this setup, and we are hoping that will take care of this issue
Originally Posted by smokinHawk
did you guys ever measure the back pressure with that yet?
how high are you reving it?
also what were they highest dyno numbers on his set up, i think i missed it.
how high are you reving it?
also what were they highest dyno numbers on his set up, i think i missed it.
#43
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Changed your name. Keep us posted. How come folks are saying rear mounted turbos will have less backpressure given the same turbo? I would also then say that the rear mount will make less power.
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John
Thank you so much for the username change, you the man
As far as the turbo we are going to go ahead and try it because we already have it.
However I should go ahead and order the T88 and have it here for standby
Thank you so much for the username change, you the man
As far as the turbo we are going to go ahead and try it because we already have it.
However I should go ahead and order the T88 and have it here for standby
Originally Posted by Pro Stock John
I get all the names and numbers mixed, up so Dave you have a T6 flanged 76mm turbo there? Based on what I've read, it's too small for your engine, but if you already own the turbo put it on and max it out. Maxing it out means you will only make a certain amount of boost, and beyond that it will just make the same power and more heat.
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Originally Posted by Pro Stock John
Changed your name. Keep us posted. How come folks are saying rear mounted turbos will have less backpressure given the same turbo? I would also then say that the rear mount will make less power.
Even if it only works 90% as good as a front mount, thats still a butt load of power. I know my car has no spool issues and is lots of fun to drive.
P.S. I also say put the gt42-76 on it and max it. It's going to be very responsive and a lot of fun to drive.
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John
What kind of power is your 98 Formula: 348ci | GT 47-88 Making ?
What kind of power is your 98 Formula: 348ci | GT 47-88 Making ?
Originally Posted by Pro Stock John
Changed your name. Keep us posted. How come folks are saying rear mounted turbos will have less backpressure given the same turbo? I would also then say that the rear mount will make less power.
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Originally Posted by DrTurbo
Is that a typo?? 26psi and 800rwhp?? I figured maybe 16psi and 800rwhp would be about right.
You figure if he had a manual tranny he would have been around 875-900rwhp... but thats at 26psi... still a ton of psi.
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Originally Posted by Pro Stock John
You guys generalize too much about dyno numbers, thats' why I posted 680 vs 800rwhp numbers.
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Originally Posted by Pro Stock John
You guys generalize too much about dyno numbers, thats' why I posted 680 vs 800rwhp numbers.
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Originally Posted by Pro Stock John
You guys generalize too much about dyno numbers, thats' why I posted 680 vs 800rwhp numbers.
People need to start taking type transmissions into account when looking at numbers. With a non-lockup converter you don't get accurate numbers. Dyno's are only supposed to be used for tuning.
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For now I just go off of facts, I went 9.4@143mph at the same raceweight and with the same converter and everything in my car.. at 680rwhp. So I like to think that I will go 10mph faster with the turbo setup. I have some valvetrain problems but we'll see if that makes a difference in anything. After reading around, I basically found that most A2/A3 dyno numbers are all over the place.
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Originally Posted by FastCashDave
The physical size of this thing is larger that my T88.
This thing is a monster.
This thing is a monster.
But not bigger then an S88
![Devil](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_devil.gif)
![Devil](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_devil.gif)
Like realquick said... you can always swap it out for the S series turbo's from Jose... if ya go with a Reg 88mm turbo with a T4 flange you would have to change piping and other things..... ALL of the S series Turbo's swap out and bolt in exactly the same as the GT42-76 with a T6 flange... i know... thats what we did with mine....
![The Jester](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_jest.gif)
![The Jester](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_jest.gif)
PSJ,
Dont worry buddy... Dyno #'s dont mean crap.. track #'s is where its at.....
Kyle
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Originally Posted by NA$TY-TA
But not bigger then an S88
Like realquick said... you can always swap it out for the S series turbo's from Jose... if ya go with a Reg 88mm turbo with a T4 flange you would have to change piping and other things..... ALL of the S series Turbo's swap out and bolt in exactly the same as the GT42-76 with a T6 flange... i know... thats what we did with mine....
PSJ,
Dont worry buddy... Dyno #'s dont mean crap.. track #'s is where its at.....
Kyle
![Devil](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_devil.gif)
![Devil](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_devil.gif)
Like realquick said... you can always swap it out for the S series turbo's from Jose... if ya go with a Reg 88mm turbo with a T4 flange you would have to change piping and other things..... ALL of the S series Turbo's swap out and bolt in exactly the same as the GT42-76 with a T6 flange... i know... thats what we did with mine....
![The Jester](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_jest.gif)
![The Jester](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_jest.gif)
PSJ,
Dont worry buddy... Dyno #'s dont mean crap.. track #'s is where its at.....
Kyle
![The Jester](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_jest.gif)
#58
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Originally Posted by 2000 Tran Zam
Says the guy with 850+rwhp through a A2 ![The Jester](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_jest.gif)
![The Jester](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_jest.gif)
ha ha ha ha LOL
![The Jester](https://ls1tech.com/forums/images/smilies/LS1Tech/gr_jest.gif)
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Originally Posted by FastCashDave
When we first put my setup together we had some big back pressure issue's.
We were only running one 46mm wastegate
So we added another 46mm wastegate and It fixed it.
So we are putting 2 36mm wastegate's on this setup, and we are hoping that will take care of this issue
We were only running one 46mm wastegate
So we added another 46mm wastegate and It fixed it.
So we are putting 2 36mm wastegate's on this setup, and we are hoping that will take care of this issue
The wastegate im using is a 48mm Turbosmart unit and i have no probel even when trying to run 8psi....
Kyle