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TH400 tuning help

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Old Oct 8, 2004 | 12:13 PM
  #1  
Ultra Z's Avatar
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From: Germantown, MD
Default TH400 tuning help

First off do you have to have the spedo connected to have a perfect tune? (I dont have a speed sensor)

My tune now is almost perfect except for at random times when comming to a stop the car will either surge for about 5-10 seconds then smooth out or just drop off and cut right out but this is rare.

Also because the car has no idea what gear it's in do I make all changes in (in park) or (in gear) tables? Or does is just know based on load values?

Part throttle and WOT seem to be fine just that weird ocasional drop in RPM when down shifting (reverse manual valve body) In other words going from load to no load seems to confuse the car into shutting down.


The car is a 99 LS1 forged 346 w/heads and cam, specs:226 226 569 569 112, th400, 4300 stall, stock ported maf, stock TB.

Any help willl be appreaciated!
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Old Oct 10, 2004 | 04:24 AM
  #2  
2MuchRiceMakesMeSick's Avatar
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From: Texas
Default

I would also like to know what needs to be changed, I will be swapping my stock tranny for a th400
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