I have a question about the tune (SCT Xcal-2) for my auto transmission and 4.10 gears. When I take off normal and once the transmission gets into 2nd gear (which happens with in a second or two under normal traffic throttle), alot of times when I floor it in 2nd gear it won't drop down into 1st, it will just BWWWAAAAAAA low down in 2nd for a few seconds before deciding to drop to 1st (and sometimes, it just doesn't drop at all, just powers through the full RPM range in 2nd). It seems a bit random, as sometimes it will kick right down to first and take off like it should, but then sometimes it doesn't. can't really pin down a particular situation in which it does or doesn't happen.

I'll to be more observant next time, and I'll try and take note of my RPM the moment I go WOT. But definitely feel like it should be dropping to first, it's not even mid RPM in 2nd. Is there a way on my tuner to change that? Every other gear seems to work fine (like if I'm in 3rd, 4th, or 5th) it drops down nicely, but for some reason not in 2nd. I didn't recall this happening before the gears and tune.

Oh and also, under normal throttle, the car seems to shift from 1st to 2nd very quick, the RPMs hardly go up in 1st when the transmission shifts into 2nd gear. It happens so quickly that when under a light throttle I can hardly even tell that the car has shifted into 2nd gear, the RPMs hardly change at all, as if first gear wasn't even there. This issue doesn't happen when I'm on the throttle a bit more, it will stay in first for a bit, then go into second like I think it should. I have a feeling this might be related to the down shift issue. I'll head out tonight and take note of the RPMs

Thanks,

Daniel

 

gear ratio from 1st to 2nd is very slight, so it's a quick shift. I also don't think 1st will take you much past 20mph. If you want I can track down some graphs from when I had a g-tech hooked up and let you know. I had with 4.10's and 3.31s.

 

1st gear can take you past 40 but @ 6000+ rpm I believe...

-Dan

 

yea, 1st will take me pretty fast when I'm on the gas, but under normal throttle it shifts around 1800 RPM or so, which to me seems a little bit low, the rest of my gears shift at least 2200 or higher under normal light throttle driving. I guess it's just the ratio, first is really low down there, so 2nd can kick in quickly with no problem.

 

I don't know exactly what tune you're using on the XCal, but if it's a canned one, I suggest you get a more customized tune from Doug (BamaChips).

 

Or just adjust your shift points till they're where you want them with your tuner.

 

just grab the shifter and rip it all the way to '1' and hold on tight!!!

 

how exactly do I do that? I saw a few parameters in the tuner for transmission, but I don't know what they do. There wasn't really any help book with the tuner either.

 

I haven't messed with mine for awhile but I'm pretty sure you can adjust the shift points up or down in 2 MPH increments. I believe it says Shift point 1-2, shift point 2-3...etc. I'll look in the morning and update.

 

I think I remember that as well, but I thought it was for WOT

 

That very well may be true. I'm not sure exactly what JDM did in my tune but the shifts are definately at higher rpm's than before even at normal driving speeds. Try it and see. I jacked around with my shift points with my old Diablosport tuner and it seemed to make a difference even when just driving normally. You can always put the shift points back to the default setting easily if you don't get the results you're looking for. If that doesn't work call JDM. They're the auto tranny gurus in my opinion and Jim,Sr. is one of the most capable 05 up tuners around.732-780-0770.

 

I looked at the tuner again today, and the only parameters I see that seem to be geared towards the transmission are the WOT shift points (adjusted in miles per hour, + or - the factory settings, I assume) and then 'shift press' I believe it was called, which I assume is shift firmess (changed in percentages, mine are all set to +25).

This really bugs me, I got this tuner so that I could tune my car, but there aren't really that many parameters to change! I'd just like my gears to stay in gear longer during normal/moderate driving. Like say for instance if I want to make a right turn at a light, and then floor it. By time I'm finished making the right turn the car is already in 2nd gear! it has to down shift back into first when I punch it. If the car would stay in the gears longer I think it would be much more enjoyable to drive :-)

Oh well, I guess I shouldn't be complaining, I didn't want a manual transmission (and I still don't!) I guess I should just live with what the transmission does.

 

It will do pretty much anything you want it to do... if you know how. Just having the handheld tuner isn't enough; it's only an interface. There are literally hundreds (if not thousands) of parameters which you can change. You need the correct software (and knowledge!!) to really maximize its capabilities. If you do it wrong... well, it could get ugly. That's why guys like Doug, Lidio, Adam, et. al., get paid for their efforts. They know how to tune!

 

Zackly, Jim at JDM told me there are 180+ adjustable parameters for the 5R55S tranny alone!!!!

 

eh, that sounds like scam, paying for the tuner, then paying for someone to tune it! haha!

I have been talking on the SCT forum, and I found out that I actually have the incorrect tuner version to change the transmission parameters, as soon as I get updated to the correct version, I'll have the parameters available to adjust, then, it's just trial and error I suppose. Just don't move the parameters to far at a time! haha

 

Good luck to you... I hope you don't F something up too bad using the "trial and error" approach.

 

we'll see! It's not my daily driver (I walk to work!!) So it wouldn't be a complete disaster I just use my car as a weekend pleasure car