Dyno 402 T76GTQ ### in
Originally Posted by 02SSLE
Well guys my new numbers are in. The car put down 644RWH and 743 RWT at 14 PSI. The AFR is 11.5 so it's a really safe tune. The Turbo is pretty much maxed out. It will not produce any more boost. We back the turbo back down to 80 percent so not to hurt the turbo and it put the numbers down above. With it maxed out at 100 percent it only put down about 10 to 15 in rwh and rwt. What do you guys think about this? Dyno graph added http://video.ls1tech.com/video/f000a...6a0142821c.htm
The reason I say the numbers look a little low is look at what EPP just posted up with their STS 67 rearmount turbo.... less cubes... lot less turbo... more HP and TQ.
I think your setup has alot more it can give ya.... just gotta figure out where its choaking at.
Well guys my AR is wrong size for my Compressor won't fit. It is a 86 or something to that sort. It measures 85.5 in the inner so the turbine wheel won't fit in it. I did do more testing. The 76 seems to not be even close to being done. If I had a bigger AR side housing It would work. I drilled and taped the TB and found I am only losing maybe 1 psi threw MAF. I had to turn the boost controller down to 20 to only get 15 psi now. The only thing I know I might have not been doing wrong before is Not having Wide open throttle. I guess that's the back up boost in cold side pipeing. Anyway the thing flys now. The first time I have been able to run it hard with no problems. That being said I think there is much more power to be made but I have sold the turbo and have to take it off next weekend. The new one will hopefully be going on.
How far open was the throttle? Are we talking 80 degrees, or less? That AR on the exhaust side was a real mistake by some one. Only a inexperienced builder would have spec'ed out a .81 ar on a 402" engine. A .96 ar should have been the minimum and a 1.XX would have been better.
Your 3:1 pressure ratio is on par with an on center exhaust housing.
Ryan K.
Your 3:1 pressure ratio is on par with an on center exhaust housing.
Ryan K.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo I guess it was because I wasn't holding the throttle all the way open because of new intercooler flowing so much better. I have the boost controller set at 20% which before when we dynoed it we had it set at 80% to acheive the numbers I made then. So the T76 IMO is not near done with this setup. But I am experienceing clutch slipage. I was talking to one of my friends locally and he told me that he put a 0Z700 SB in another car with 408 and come to find out there is a problem with the crank seal in the back of it where it's gun drilled. There is a freeze plug in it. Well oil seeps around the freeze plug. He was told to pull the piolt bearing out and rub some silicone around the plug. I will pull my tranning this week some time and check it for that. Because I do have a leak coming from back crank area. Not much but some moisture around the bottom bell housing and trans a little slit on bottom. If it's a problem with his N/A car It should be even bigger prob with mine. Especially with back preasure issues.
Oil was leaking out the back of crank shaft it is gun drilled the oil galley plug was the problem. I put some silicone arond it and cleaned everything up. It was all over the place. Seems like Eagle would tell you about this problem.
TECH Addict
Joined: Jul 2005
Posts: 2,153
Likes: 3
Originally Posted by RealQuick
see if a log setup (especially on big cubes) can break the infamous 700rwhp mark?
Originally Posted by engineermike
I can guarantee you that a log setup and 388 cid with a T76 will go over 700 rwhp, even through an auto/loose converter. I made 695 rwhp with my 40 mm wastegate wide open.
