I absolutley loved the 7AT in the370Z. It shifted sooooo fast. Easily would bark the tires going from 1st to 2nd and sometimes from 2nd to 3rd if the conditions were right. The G37 7AT doesnt shift near as fast, I go into the redline almost every time i shift from 1st to 2nd under really hard acceleration. I just expect it to shift faster. Is this something that can be adjusted within the ECU?

Now, I drove my Z alot harder than I drive the G, do I need to go out and do a bunch of hard accelerations for the trans to learn what I want it to do?

 

I did some searching and it seems an Uprev tune can change the shift parameters thru the line pressures or something like that. I wish I could just get this trans setup to shift like the 370Z.

 

Honestly I dont think so, I can not get my tires to chirp in any gear, an I have a lot more than stock HP..

 

The G weighs more then the Z as well. I would think that it has the same trans in it.

 

^ +1 What Buckeye G said

 

you wont being X

 

Its the amount of time it takes the G trans to shift gears that bugs me. From the time I hit the paddle it goes up another 3-400 rpms before it starts to shift and then it takes another second or more to get to the next gear. With the Z the shifts happened very quickly, lightning fast.

 

First doing a bunch of hard launches is a good thing, but don't expect it to be like the Z. They are 2 very different cars I don't care how much alike poeple think they are.


I have often told people even though they say the 2 cars are the same they are not, the trannies are different. Also I would bet the gearing has something to do with it as the gearing in the Z is lower than the G. I really don't manually shift the G much anymore (except when passing or down shifting at times), but I ALWAYS manully shift the Z. The Z definately shifts faster. It doesn't bug me as my G still shifts good, I don't have the complaints others have. I probably drive the G slower and not in such a "spirited" way. Uprev seems like a tune so you can't go wrong with it but you really can't expect the G to be like the Z.

 

The G and Z 7ATs are identical.
According to the FSM, the 2010 G37, and 2010 370Z have identical gearing, identical torque converter stall speeds.
Identical 3.357 differential ratios.

It's in the programming.

 

Uprev can only get you more solid shifts, by programming expected torque.
It can not make it shift quicker. Ive looked into it.

 

I'll agree with this. And this has little to do with the Uprev Torque Management tables...

The trans has it's very own ECU. So far, no one has actually tapped into THAT. This is the hidden unknown component that has the key to quicker shifts (and probably firmer ones.)

I would not doubt the Infiniti, based upon the target user, has been delivered a changed set of parameters better-suited to the clients who drive them. (So thinks Nissan.)

The difference between D and DS: Trans ecu makes it respond a bit faster and hold gears longer.

I once went into limp mode for some reason, trans related. Although the car would not go over 2500rpm (?) I was amazed at how firm and quick the shifts were. It felt like the limiters came off.

Pat at Level Ten educated me how the ECU will, just before it shifts, drop torque. This makes the transition smooooth. The Uprev TM tables lift this, apparently.

^^^ Some of this is speculation, because I don't know electronics, but I'll bet I'm not far off base.

Coop

 

My 7AT will usually chirp the tires shifting 1st to 2nd (and sometimes 2nd to 3rd) if I keep my foot flat to the floor. It is a 2009 though, and I believe the shifts have been softened up with some of the more recent software updates. My car does have the annoying delay when upshifting manually - you need to pull the paddle about 1/2 second early. Generally I only use the paddles when the transmission won't kick down on its own (no first gear kickdown at all).

Greg

 

Update: it seems that driving more aggressively has made the trans shift better and closer to the way my Z shifted, close but still not as fast. I have found that if I shift lower in the rpm range - like about 5500 rpm - it shifts faster and pulls harder right into the next gear..... Very little lag. Now if only I had a shift light!!!,

 

Hmm. Would retrofitting an ecm from a wrecked 370 get these shift parameters working? I wonder if this is even possible.

 

My Z definately has lower gears than my G. Trust me, in second gear my Z hits 7k about 10mph lower than the G. This was figured out in an autoX thread. I couldn't believe people in G's would run in second gear only as I HAVE to use 3 as well on most courses. Thats when I went out to see the difference.

Oh and like I said they are totally different, I didn't say they had different part numbers. I love when people tell me I am wrong when I can walk out and drive both cars and tell you from EXPERIENCE what I find to be true.