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high RPM problem

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Old 06-08-2009, 08:51 PM
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Default high RPM problem

When I am racing car and go into 3rd gear (th-350) the car is cutting out like its hitting a rev limiter (it is set to 8000) but it isnt. I am data logging car with HPT with a LC-1 wideband. There are no big swings in AFR, no knock, inj duty cycle is at 50-60%. I am running VPMS101, fast 96, MS4, PAT STG 3 5.3 with -5 cc pistons, Pat gold springs, tr55 with 40 gap, walbro 255 and harlin sharp rocker arms. However this problem was present with stock rocker arms. I am running 24.5 deg of timming. When I run the car on the street in thrid gear with no problems. I am at a lost of wehat wrong with car. any ideas out there
Old 06-09-2009, 09:23 AM
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Auto Transmission? It sounds like your 3-4 clutch pack might be going out. Not sure though.
Old 06-09-2009, 09:36 AM
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Originally Posted by fasttagurl
Auto Transmission? It sounds like your 3-4 clutch pack might be going out. Not sure though.
A th350 is a 3 speed auto, so it doesnt have a 3-4 clutch pack.

Bandit, does it feel like its in the motor or transmission?
Old 06-09-2009, 09:41 AM
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It sounds like something in the trans or tuning issues. I've had the same issue before but with a different trans.
Old 06-09-2009, 03:45 PM
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It's something in motor/tune. When I put in it thrid it goes into gear but motor sounds like it hit a rev limiter. Any ideas what in tune would be off. And what fixed ur problem?
Old 06-09-2009, 04:34 PM
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But it doesnt do it WOT in any other gear? Thats wierd.

Is the ignition stock?
Old 06-09-2009, 06:32 PM
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yes the ignition is stock
Old 06-10-2009, 11:57 AM
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Originally Posted by bandit383
It's something in motor/tune. When I put in it thrid it goes into gear but motor sounds like it hit a rev limiter. Any ideas what in tune would be off. And what fixed ur problem?
Have the transmission section of the tune checked out. I bet it's something in there. Mine was actually both my transmission (burned up a little after 400 passes) and the tune parameters/values were incorrect causing it to hit the limiter on every WOT. It's being tweeked this week by my tuner but so far after a freshened trans it has not hit the limiter again and goes through every gear. I'm not a tuning expert, but I believe some of the values in the trans section have to correlate or it will not react properly. Have that tune checked out ASAP before something in the trans is possibly ruined!
Old 06-10-2009, 02:28 PM
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not runnng a 4l65 running a th-350 .. Car was a six speed
Old 06-10-2009, 04:18 PM
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Since the ECM has nothing to do with the TH350 and it only does it in high gear, than I would have the trans checked out.

I would think if it was a tuning problem it would do it in 1st and 2nd as well.




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