early shifts
early shifts What would cause my trans to shift way to soon? My shifts are set at 6200 and 37 mph and 70 mph.I am not sure if the car is leaving in second gear or not.My 60 ft times were 1.7 on a marginal track which is about normal but the car feels like it only makes one shift.The trap speed is 108 which is normalThe gears are 3:73 and the trans is 4l60e.I logged 2 runs that I can send to someone to try and decifier what is going on.I am new to this and trying to figure this out.The car also has been dyno tuned and I did not have this problem previously.Thanks.
Times like this are when I wish I had HP Tuners and not just EFI Live. I wish I could look at those logs. Is it doing the same behavior on the street? Has it been having any issues prior to this? Do you launch the car in 3rd at the strip?
Drives fine on the street actually perfect. I did not have these problems before.Car went 11.98 stock motor with this trans and converter.Had some work done (cam) and I have been battling shift issues ever since.Not sure if I have a tune issue or other problem?Where should my force motor setting be?
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Okay, so it hasn't shifted correctly SINCE doing the cam? Only BEFORE the cam did it shift correctly? Is that what I'm understanding? So even with the NEW cam, it shifts fine on the street??
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Verdad Gallardo Since cam I had problem with hitting the limiter( 6500) but my gear ratio was not set correct ,set 2:73 needed 3:73.I took the car back for gear ratio change.Since then I have been having early shift issues.I did have 3 passes out of 12 that it acted correctly.Car presently drives perfect on the street.
Wow, very strange. I really wish I could look at the tune... it's probably something easy. How big is your stall converter? Is it the 4000? If so, I had a pretty similar setup as you (before going to 4l80e), and my transmission tune might work for you. I had a 4000 converter and 3.73 gears in a 10 bolt with a 28" tire, so it may work. My trans never had early shift issues; track or street. I could take screenshots of everything and you could put them into HP Tuners; assuming you can make sense of the data since the graphs are laid out slightly different in HP Tuners. Let me know if you want to give that a shot and I'll PM the information to you tonight when I get home and have access to EFILive.
Got your PM, I will work on getting you the data later tonight. What gear are you doing the burnout in? I suggest using 2nd as you're less likely to hit the limiter and the tires will turn at a higher mile per hour, making it less difficult to get them good and hot. With a good converter, it shouldn't have any issue flashing right up and spinning them right away. Then after completing the burnout, come to a full stop and shift it up into 3rd. Complete staging and let the computer do the rest.
I'll shoot you an email a little later.
I'll shoot you an email a little later.
Joined: Aug 2007
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From: Turnin' Wrenches Infractions: 005
Are you getting any misfires? Is your mph set up to trigger first, then rpm for your shifting??
Meaning if you want to shift at 35mph and 6500rpms, you would set your mph for shift to be 32 or so. You want the computer to meet the mph criteria first. Are all your shift tables matching?>Reg>Performance>Hot, what about your other shift tables that coincide, do they match each other? I didn't look at the above logs but is the trans being commanded to shift early? If it is then its in the tune. The trans only does what its told.
Meaning if you want to shift at 35mph and 6500rpms, you would set your mph for shift to be 32 or so. You want the computer to meet the mph criteria first. Are all your shift tables matching?>Reg>Performance>Hot, what about your other shift tables that coincide, do they match each other? I didn't look at the above logs but is the trans being commanded to shift early? If it is then its in the tune. The trans only does what its told.
I have read his thread several times.I logged the car to try and figure out what is going on but I am new to this and not sure how to decifer the log.I am thinking it is in the tune.My tables are set at 37 mph and 70 mph and 6200 mph.My misfire tables are maxed out except in cylinder mode idle moving and medium rpm tables.My previous tune had these tables maxed out. Could this be part of the problem?
Last edited by nj02z; Jul 16, 2013 at 04:35 AM.