No boost need help please

87bluenational

New Member
Joined
May 8, 2006
Here it is i have a 87 grand national, last year i had a stock turbo and stock injectors,with a 93 chip from poston. A 3 inch maf pipe and a 9 inch k@N air filter. I went to the track with slicks and a bad rear end and i could only get the boost up to 7lbs and ran at best 14:50. So this off season we put a newer rear end in, took the stock turbo off and found that it had shaft play and real bad fins. So I figured its out with old and in with the new. I purchased a rebuilt pt6376 and figured lets get 60lbs injectors and headers from poston(using the old crossover pipe) rebuilt transmission with a 2200 torque converter. A turbo tweak chip from Eric. So now i have the same problem but worse. Boost is only going up to one when break torque. And only 7 maybe 8 when shifting from 1st to 2nd. I have not had it to the track yet and can not get anywhere longer enough to let it go through all 4 gears. We did some tests, one was if the waste gate was working and put new vacuum hoses on drained the intercooler just incase any oil was in there. I need help. I do believe that this turbo should get at least 15-17lbs of boost on take of and 1 is a for cry. Any help will be greatly appreciated.
 
Are you still running a factory elbow in your downpipe? If so the puck maybe to small and exhaust is getting around the puck, keeping you from building boost.
 
Here it is i have a 87 grand national, last year i had a stock turbo and stock injectors,with a 93 chip from poston. A 3 inch maf pipe and a 9 inch k@N air filter. I went to the track with slicks and a bad rear end and i could only get the boost up to 7lbs and ran at best 14:50. So this off season we put a newer rear end in, took the stock turbo off and found that it had shaft play and real bad fins. So I figured its out with old and in with the new. I purchased a rebuilt pt6376 and figured lets get 60lbs injectors and headers from poston(using the old crossover pipe) rebuilt transmission with a 2200 torque converter. A turbo tweak chip from Eric. So now i have the same problem but worse. Boost is only going up to one when break torque. And only 7 maybe 8 when shifting from 1st to 2nd. I have not had it to the track yet and can not get anywhere longer enough to let it go through all 4 gears. We did some tests, one was if the waste gate was working and put new vacuum hoses on drained the intercooler just incase any oil was in there. I need help. I do believe that this turbo should get at least 15-17lbs of boost on take of and 1 is a for cry. Any help will be greatly appreciated.


With a 2200 torque converter behind a PT63, that explains why it probably seems to take forever to build boost, even after launch. :eek:
If you stay in it through 3rd gear does the boost get up to at least 15? What type of wastegate actuator did you get with the new turbo?
 
yes i am running a stock elbow with the down pipe that came with the car. I can't be sure that it is the stock down pipe though. And i have not had a chance to get it into third gear. And the boost seems to go down a little after the shift from 1st to 2nd instead of climbing like i think it is suppose to do. Please keep seeding the tips. The only thing about the torque converter is i would hate to put a bigger one in and still have the same problem with the boost not going over 1 to even 5lbs. Keep all the tips and anything that you think can help coming. I greatly appreciate it.
 
Yes i have as tight as it would go. I also bought a rcj gasket and when i put it on it did not line up exactly and burned it right up. So now i just have the stock elbow bolted right up to the turbo with some high temp sealer. If i have a small exhaust leak from were the hearders bolt up to the crossover pipe, would that not allow the turbo to build up but I still get boost after i take off? Any hints and tips just keep them coming!!!
 
The wastegate puck is not sealing or you have a leak between the turbo and the intake. Check all couplings to make sure nothing blew off.
One other thing would be the y fitting for the wastegate. Make sure its installed right.
 

Attachments

  • y.jpg
    y.jpg
    20.8 KB · Views: 68
Hey Rick how is it going. As you can see i haven't had a chance to fully enjoy your toy you sold me. It's been fustrating. But hanging in there. I will check all fittings and couplings to make sure nothing blew off that i missed. Also will check the puck to make sure it's flush and the y fitting. I may have to upgrade the torque converter and go to a aftermarket downpipe. But that all cost $$$ and it will have to wait for now. Thanks for all the tips if anything else that anyone thinks of just post and i will read it. Thanks again
 
The next things to take a look at would be a restricted exhaust or even worse, a flat cam. :eek:
 
wow a 2200 stall with that turbo. theres your problem right there. you need a converter.
 
Top