Auto LE5 Tranny help

Can someone please look over this tune and give me a little insight on what might be a problem. I am tuning an 07 LE5 with an auto tranny; I have the engine part running find. But the tranny tuning is new too me. Now what is happening is when he is going WOT the Tranny is not shifting in the next gear it is sitting the bouncing off of the rev limiter and only shifts when he lets up for a slight second. Under normal driving conditions the tranny is shifting tights and faster but I am just having problems with the performance settings. So any insight great :pray:

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Originally Posted by REDFOCZ

Can someone please look over this tune and give me a little insight on what might be a problem. I am tuning an 07 LE5 with an auto tranny; I have the engine part running find. But the tranny tuning is new too me. Now what is happening is when he is going WOT the Tranny is not shifting in the next gear it is sitting the bouncing off of the rev limiter and only shifts when he lets up for a slight second. Under normal driving conditions the tranny is shifting tights and faster but I am just having problems with the performance settings. So any insight great :pray:

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Red,
I don't have the HPT software on this machine so I can't view your tables without a screenshot.

I can tell you though I had a similar issue with my HHR where it would hit 7400 RPM before it would shift. The solution was the rpm, and the mph that the vcm looks at for the shift. Say you have your MPH set to 40 MPH but the shift rpm is at 7000 RPM.

The VCM for some reason needs both of these numbers to arrive at the same point or it defaults to the higher one.

I'd look at upshift RPM as well as the MPH and see if one is much higher in relation to the other.
Here is a thread where I got some help with toque reduction, which might give you an idea: http://www.hptuners.com/forum/showthread.php?t=15572


Jim

you have your shift point set at 7100 rpms & your rev limiter at 7150, thats not very much room for error if you ask me.

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Originally Posted by Bill@HPTuners

you have your shift point set at 7100 rpms & your rev limiter at 7150, thats not very much room for error if you ask me.

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Any insight would be great. So you are saying bump up the engine rev limiter?

Could you post the stock tune to compare? The shift pressures look very odd. I would either lower the WOT shift rpm, or raise the rev limiter depending on what rpm the engine can take.

Russ Kemp

I'll post the stock tune for you to compare when I get home tonight.

41 mph in 1-2 shift was over 7300 rpm on my 2.4 with boost. I lowered that number which I see you have in yours.

I'd bump the rev limiter to 7300 ish and drop the mph to 39-40 max lower the shift point to 6800 and see if it shifts out ok.

Jim

Alright sorry for taking so long to get back here to post up a copy of the stock tune vs the new tune that I am running on the car, look them over and let me know what you think. I am still running into the issue of him hitting some type of rev limiter even though I have all of the settings higher then the shift points. I am at a loss for why it is not working. But the real pussler is while I was in the car tuning it, it was shifting fine from 1-2 and 2-3 but as soon as the guy leaves and heads home and places a few more miles on the tune he can not get it to shift into any gear while under WOT. I have left his line presure at the stock numbers because he has a B&M shift plus on there and no tranny cooler, so I do not want to put to much strain on the tranny right now.

Any help that you guys might have would be great I am getting a headache over this automatic tranny tunning :banghead:

Make the changes as shown. Also return the WOT shift speed table to stock, and lower the WOT shift RPM to 7000.
Having the rev limiter so close to the shift RPM is not a good plan. I would remove the B&M shift plus.

Russ Kemp

Thank you Russ I made the changes that you sugguested. Can you look this over real quick and let me know what you think? :D :worship:

Your changes look good. You can make the changes as shown so the trans downshifts into 1st gear easier, and set the TCC to lock up better.

Russ Kemp

Thanks Russ I made the changes you just posted aswell, I cant wait to meet up with this guy to see if it works, Ill keep you guys updated

for some reason its still not working russ i will post up the logs later