4L60E Shifting Problem - Third Generation F-Body Message Boards

1986lt1boy · 03-29-2008, 06:28 PM

Hello, I just got home from drag racing today at englishtown,NJ. I have a 1994 396 Lt1 stroker motor with a built 4l60e Tranny. While i was making my 1st pass today on the track I had a great launch 1.66 foot time but when it came time for the car to shift from 1st into 2nd gear it just kept bouncing off the rev limiter until i let off the gas and then press it again so the car would shift.As i did this a big puff of black smoke came out the tail pipes. It shifted through all of the other gears fine. It also has no problem shifting around town while driving normally. Anyone ever come across anything like this or possibly know a fix?

87zjeff · 03-29-2008, 07:08 PM

have you had your set-up tuned properly?

Z28ricer · 03-29-2008, 07:23 PM

Chances are your programming is set for too high of a MPH for the TPS value, your hitting your rev limiter before the computer see's the speed its programmed to shift at since the 4L60E uses MPH and TPS to determine shift points.

Pro Built Automatics · 03-29-2008, 11:25 PM

Does it do this on the street? Does it do it all of the time at the drags? Or just on a hard launch.

1986lt1boy · 04-04-2008, 08:50 PM

Well I have not tested it on the street. This problem occured on the Race Track under a "hard launch" The car cut a 1.66 60 foot. I only ran the car down the track 4 times the 1st time it did not happen. The other 3 it did

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