Car makes boost but it's really slow.

13xturbo

Member
Joined
Jun 4, 2012
The car is an 87' GN it has a ball bearing TE-44 on it with 60lb injectors a walbro pump 4" intake with 3" stainless exhaust with no cat. Alky Injection trans is mildy built. So almost three years ago the car was running great had great boost really quick but then one day at the track the car just stopped building boost off the foot brake. Or shall I say really slowed down. I have done a number of things to check the car and still cannot figure it out. The car has a turbo tweak alky chip.
Things I have checked or changed to try and solve.
1. Brand new TE-44 turbo
2. Brand New Converter 12" with 2800 stall
3. New Coil pack
4. New Mass Air Flow sensor
5. New Wastegate Puck and yes it is making up well.
6. Smoke tested it and found a couple small leaks in headers and welded them up.
7. Checked fuel pressure and it set to spec and doesn't drop when car is trying to build boost
8. Checked voltage on tps sensor at idle and wot and both were great.
9. Changed fuel filter.
10. New spark plugs gapped to .30
11. Leak down test on all cylinders and all were great.
12. Compression test on all cylinders and all were great.
13. Pulled intercooler and checked for leaks or blockage and was great.
14. Cam sensor was checked for timing and was good.
After fixing the minor leaks on headers I brought the car to the track and tried staging and building boost again and it was so slow building boost probably about 25 seconds to build 10lbs of boost.
Please help running out of things to check
 
It seems like you are just shooting from the hip . without any data there isn't much anyone can do but guess at your issues . I would suggest before you buy anymore performance parts you buy a scanmaster or powerlogger to acquire data to help you diagnose your problems .
 
I have a scanmaster and all readings are where they are supposed to be and no timing is being taken away when car is building boost.
 
What's your A/F during spool up? How much alky are you spraying ? When does the alky come on? Bet you are runing stupid rich but don't know just taking a educated guess
 
The car had run fine with all of the performance parts installed before so I don't know why the car would all of the sudden be rich???? Everything was installed two years prior to having this problem then I bought a new TE-44 because I was told mine had a bad bearing and that was my issue so I replaced it with a new one. Then someone on here told me it was my converter so I bought a new one and that didn't fix it. I am not sure why after two years of running the car at the track and on the street it would all of the sudden become rich and not spool
 
I can get the car out of my garage in a little bit and post all scanmaster numbers at idle and spool up just so you have records though. Thank you
 
So the car makes good power just slow spool, or also not making power when the boost finally comes up? Or the boost never comes up?
Stock unopened long block?
Runs and drives normal other than unable to build boost?
Was the old turbo actually still good?
 
So the car makes good power just slow spool, or also not making power when the boost finally comes up? Or the boost never comes up?
Stock unopened long block?
Runs and drives normal other than unable to build boost?
Was the old turbo actually still good?
The car seems to be down on power took it to the track on Friday car ran the best of 7.90 leaving with 10 lbs of boost where as before the car would easily build 10-15 lbs of boost on the foot brake and the car would run 7.3's. The motor is completely stock car only has 32,000 original miles on it. Yes the old turbo was still good but upgraded to a ball bearing TE-44 when I bought new which should build boost faster
 
Oh and the alky is set to specs for the kit I purchased it comes on at 10lbs of boost.

So, if I understand, alky on at 10, and you are leaving at a min of 10.
Alky is spraying while you are building boost. Alky Control kits have an optional wire scheme, to shut down the alky flow, when building boost for launch. Is it hooked up? You can hook it thru the brake sw.
Shut the alky off, boost it to 10/12, and see how it spools.
Whose converter? I'm wondering if the converter fins laid over, or killed the stator sprag? Trans getting hot?
 
When the transmission was reinstalled with the new converter, did you play with the kick down cable? Is the kick down cable hooked up correctly on the transmissions side? and set properly on the dog house bracket? Lastly, do you have a guage to shows you vacuum? if so, what does it read at idle? If your not between 16 to 18 inches of vacuum, and it's reading closer to 0, you have a vacuum leak somewhere. Wouldn't hurt to put a fresh set of plugs in the car either.
 
The car seems to be down on power took it to the track on Friday car ran the best of 7.90 leaving with 10 lbs of boost where as before the car would easily build 10-15 lbs of boost on the foot brake and the car would run 7.3's. The motor is completely stock car only has 32,000 original miles on it. Yes the old turbo was still good but upgraded to a ball bearing TE-44 when I bought new which should build boost faster
A bb 44 is much faster spooling than the non bb version.if you didn't see that when you put it in then that may be part of the problem.changing the converter could be the other problem.since there are issues you should be data logging or watching gauges to see what's happening.afr and fuel pressure would be on the list.
 
Do you still use the flexible air intake hose and stock MAF sensor? Have you tried running without the air filter? Have you tried opening up the exhaust?
 
So at an idle it has 16 inches of vacuum.
While building 5 lbs of boost the scanmaster numbers are
02-816
KR-0.0
AF-90
LV- 198
BL-129
ATS-102
IAC-124
cc-67
 

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Do you still use the flexible air intake hose and stock MAF sensor? Have you tried running without the air filter? Have you tried opening up the exhaust?
No it has a 4" aluminum air intake with a 4" cone filter that I tried removing to see if it made a difference and the exhaust is 3" stainless straight with no cats or mufflers so I would hope for no clogs there
 
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