Full spool, shift, then bog. Ideas?
08-01-03, 07:53 AM
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Full spool, shift, then bog. Ideas?
I finally got done breaking my reman motor in and was able to start boosting it yesterday. We were planning to tune it, however, noticed 2 problems.
1) Won't boost above 9 lbs in either primary or secondary. I am running an HKS EVC boost controller and before the reman I was able to hit 14lbs. A silicon hose job was done at the time of the reman. Maybe a hose off under the manifold? It doesn't seem to be a problem with the sequential system since it's buildling the same boost on the primary and secondary, and the transition is normal.
2) About 50% of the time, when I run hard through a gear (ie 9psi), then shift, it will bog down terribly and won't boost. But if I back off the throttle, then punch it again, boost will build fine. All the couplers are new and don't seem to be leaking. Maybe sticking injectors?
Any ideas on either? Thanks.
1) Won't boost above 9 lbs in either primary or secondary. I am running an HKS EVC boost controller and before the reman I was able to hit 14lbs. A silicon hose job was done at the time of the reman. Maybe a hose off under the manifold? It doesn't seem to be a problem with the sequential system since it's buildling the same boost on the primary and secondary, and the transition is normal.
2) About 50% of the time, when I run hard through a gear (ie 9psi), then shift, it will bog down terribly and won't boost. But if I back off the throttle, then punch it again, boost will build fine. All the couplers are new and don't seem to be leaking. Maybe sticking injectors?
Any ideas on either? Thanks.
Last edited by Scrapiron7; 08-01-03 at 07:59 AM.
08-01-03, 09:43 AM
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Mine does that when the lines going to my Profec B solenoid box gets kinked.
Perhaps you have some lines that are being kinked when they dropped the new motor in.
Im willing to bet you'll find the problem in a vacuum hose.
Perhaps you have some lines that are being kinked when they dropped the new motor in.
Im willing to bet you'll find the problem in a vacuum hose.
08-01-03, 01:41 PM
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maybe a vaccum chamber leak. Since when you back off then get back in it comes back on. I believe the site WWW.autosportracetech.com should help you out. It has a complete list of turbo troubleshooting. That test is one of the vacc. chamber tests.(back off the gas,see around 20inHg,{vaccum}, punch the gas and see if you get boost) Maybe the vacc. check valve as well.
08-01-03, 05:37 PM
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Re: Full spool, shift, then bog. Ideas?
Originally posted by bricke
I finally got done breaking my reman motor in and was able to start boosting it yesterday. We were planning to tune it, however, noticed 2 problems.
1) Won't boost above 9 lbs in either primary or secondary. I am running an HKS EVC boost controller and before the reman I was able to hit 14lbs. A silicon hose job was done at the time of the reman. Maybe a hose off under the manifold? It doesn't seem to be a problem with the sequential system since it's buildling the same boost on the primary and secondary, and the transition is normal.
2) About 50% of the time, when I run hard through a gear (ie 9psi), then shift, it will bog down terribly and won't boost. But if I back off the throttle, then punch it again, boost will build fine. All the couplers are new and don't seem to be leaking. Maybe sticking injectors?
Any ideas on either? Thanks.
I finally got done breaking my reman motor in and was able to start boosting it yesterday. We were planning to tune it, however, noticed 2 problems.
1) Won't boost above 9 lbs in either primary or secondary. I am running an HKS EVC boost controller and before the reman I was able to hit 14lbs. A silicon hose job was done at the time of the reman. Maybe a hose off under the manifold? It doesn't seem to be a problem with the sequential system since it's buildling the same boost on the primary and secondary, and the transition is normal.
2) About 50% of the time, when I run hard through a gear (ie 9psi), then shift, it will bog down terribly and won't boost. But if I back off the throttle, then punch it again, boost will build fine. All the couplers are new and don't seem to be leaking. Maybe sticking injectors?
Any ideas on either? Thanks.
for # 2 this could be normal depending on when you shift. For me, if I shift at a low RPM (prior to the 2nd turbo coming on line) and PUNCH it, the spool with be very slow. If I wait till the rpms drop below 3K RPM and punch it, it will spool instant.
I talked to a mechanic who said its the design of the turbo system,something to do with a valve opening/closing. Shift when you hit around 5500 or so, and see if your car has the same problem. For me, its only when I shift below that point and GUN it. This was the same with both my engines and both sets of turbos that i've had.
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08-01-03, 05:41 PM
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Originally posted by BigIslandSevens
maybe a vaccum chamber leak. Since when you back off then get back in it comes back on. I believe the site WWW.autosportracetech.com should help you out. It has a complete list of turbo troubleshooting. That test is one of the vacc. chamber tests.(back off the gas,see around 20inHg,{vaccum}, punch the gas and see if you get boost) Maybe the vacc. check valve as well.
maybe a vaccum chamber leak. Since when you back off then get back in it comes back on. I believe the site WWW.autosportracetech.com should help you out. It has a complete list of turbo troubleshooting. That test is one of the vacc. chamber tests.(back off the gas,see around 20inHg,{vaccum}, punch the gas and see if you get boost) Maybe the vacc. check valve as well.
ZeroBanger is right as far as I'm concerned. The spool changes depending on when you shift. If you shift low and punch it the spool will be slower than if you shift at redline and then punch it again. Play around with it if you can, see if you can figure out a pattern, i.e., when it bogs and when it spools quickly.
But I'm willing to bet it's shift dependent.
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