So I got my '94 TA up and running and decided to take it to a local auto cross to get some seat time. The car happens to have a 4L60E automatic trans. I never autocrossed with an automatic before but figured it wouldn't be a big deal. There is one less pedal after all. Boy was I wrong. First of all the shifter only goes down to "2" on this car. There's no option to lock it into first gear which would have been ideal because it was a small course. Secondly, by leaving it in any of the other gear settings it has a nasty habit of downshifting into first about half way through my corner exit and making me go into massive oversteer. I figured it would have stayed in the gear I selected ie 2nd.

My question is this: What can I do to either lock the car into a gear or be able to shift into first on demand with the shifter to add predictability? Any advice would be appreciated.

Matt

well my first advice would be to put the automatic trans in the trash barrel where it belongs, but that doesn't really help you now does it? (IMG:http://www.frrax.com/rrforum/style_emoticons/default/wink.gif)

I know on the automatic shifter in those cars can be easily modified to go back into the first gear position. There is apparently just some small tab you have to cut off and you're golden. I've never done it, but had a friend that did and I'm sure some guys on LStech can fill you in. Since you have that shifter I'm also going to assume your car has 2.73 rear gears, so you can hold 1st gear out for quite a while. The problem is that first gear is pretty aggressive and the car can be pretty frantic, especially for a new driver. It is hard to be smooth and hit your marks when your stabbing the pedal in 1st gear.

Most guys that I know that autocross with automatics stay in 2nd gear and they have custom built automatics to do the job. (some of the fastetst auto-x cars run automatics by the way) I don't know of a way to get the later 4L60s to stay in a gear and not kick down. I say if your just new at this, do the 1st gear mod and do your best to drive around it. If you're really going to get serious about it you'll need some custom work in the form of a built automatic trans or get a manual trans.

Sorry thats sucky news and doesn't really help you but a stock automatic is not meant for auto-x use, nor will it put up with much abuse like that before it overheats.

The Dodge truck I was autocrossing my first year was notorious for this. I solved that problem by buying my Camaro. (IMG:http://www.frrax.com/rrforum/style_emoticons/default/biggrin.gif) The more time I spend autocrossing my car (with a 700r4) the more I have that same problem. I start the run in first and shift into second the first time I feel it needs to and then just leave it in second for the rest of the run and it sometimes will drop down into first during corner exit. With my car I can go into first gear but because the Miller Park parking lots are so big the courses are often big enough that second gear is required. If I remember right, there was a car last year that even went to third gear on all his runs one event.

Any tips or tricks for me since I have a different trans?

hrdlydangerous

yes, there is a rubber tab on the shifter track that keeps it from going into 1st. i think you can get to it by taking just the upper console piece off and using a utility knife , just cut it out ( i have done this before, but it's been a few years and i'm gettin older.. (IMG:http://www.frrax.com/rrforum/style_emoticons/default/rolleyes.gif) ). on the LTcars this does mean you have 2.73s out back (GU2 code or something like that).

if you wanna spend some $$ but not building a full on race trans, TCI used to make a plug-n-play "brain" for the 4L60/65/80E that came with paddle shifters that mounted on the hub column, behind the steering wheel. when turned on, you controlled the trans completely with the paddles, i.e. will stay in the gear you last selected. IIRC it was about $6-700 (again, i could be way off here, so please forgive me)

or...you could do a T56 swap...it's not as bad as it sounds....but it's quite a bit more time and $$

This post has been edited by gearhead: Apr 15 2010, 04:54 AM

Mike, for your car lots of C4 guys will adjust the TV cable way out so the trans doesn't know that you're hard on the throttle, then it won't kick down to first. Make sure you adjust it back for street driving though. I'm not a very big fan of this option because the TV (throttle valve) is the only way the trans knows what the engine is doing. If I understand correctly, it also raises and lowers line pressure and such. Needless to say, hard abuse and low line pressure are not a good combo for an automatic.

The only good solution for you guys that I know of is to get the automatic built for full manual control or put a manual trans in the car.

Yeah I don't really want to be messing with the TV cable any more then I have to. The rear trans seal is leaking so I'll probably replace that, pop in a vette servo, add new gears (to correct the speedo), install the trans cooler and just leave it at that. When it finally does goes I'll probably be doing the manual controlled automatic if I can afford it at the time. I'll just hone my sliding skills in the mean time. (IMG:http://www.frrax.com/rrforum/style_emoticons/default/smile.gif)

We have a couple of guys that like to autocross late '90s Impalas, and when I've co-driven with them I've had the same problem. Their suggestion was to alter my driving technique and avoid going more than 75% throttle to keep the auto from downshifting. I've generally found I've turned my best times (in that car, not necessarily true in my M6 Camaro) using that method. At any rate, its some 'free' you can do as opposed to start building an auto or swapping in a manual.

if i remember, his car is for the GRM 2010 challenge, so i seriously doubt hes looking into swapping a trans or anything more expensive then a few bucks.

This will usually result in trans failure in even less time than the usual rate of failure for these transmissions. In other words, this is a VERY bad idea.

(IMG:http://www.frrax.com/rrforum/style_emoticons/default/unsure.gif) (IMG:http://www.frrax.com/rrforum/style_emoticons/default/blink.gif) I know but the local C4 guys here swear by it. They listen to one guy (he is one of the fastest) and that is what he does on this vette. I told him he was damaging his transmission but I don't think he believes me.

He'll likely melt it down eventually (burn up clutche packs, etc). It drops the line pressure and there is a serious risk of transmission slippage. I'm glad it works for him (for now). But use that advice at your own (probably expensive) risk.

The 94 up fbodies do not have a TV cable. I dropped off in 93 with the 700. You would to tune the computer to adjust the tranny. BranZ

Trans-Go shift kit. You can select what your tranny does and how hard it shifts. I got the lightest setting, works pretty well and I enjoy autoxing it ('97 TA).

We're well aware of that, we were talking to Mike with his '87 IROC.



I had a Trans Go kit in my IROC years ago when it still had the trash-o-matic in it. This does not delay kick down does it? Are you just talking about improved shift firmness?

Gearhead, Thanks for the advice. I'll see how that works out. I'm planning on gutting the car anyway so the console will go bye bye.

This is my Grassroots $2010 Challenge car so I can't spend a lot on a fix. If I have to use the 75% throttle method then so be it.

Thanks all for your input. The next autocross is May 2nd so I'll keep y'all posted.

Matt

It does not help kick down, but it did help firmness and you could set it up to not over-ride your shifting. It was a pretty flexible kit as I remember.

Do you happen to have a part number for the kit?

Not handy, that was over 10 years ago. I see plenty of them listed on Summit's website:

http://www.summitracing.com/search/?keywor...ansgo&dds=1

You can get the Trans-Go kit from about anywhere. It's the ONLY shift kit i"d ever use. I had one in my automatic back in the day.

I was playing around with the car last night and here's what I found. Maybe this will be helpful to others here. I removed the shift knob and removed the top of the console and the attached wires. The shift lever has a spring loaded wheel that rides on a rack with detents in it. That's what gives you the "clicking" when you change gears. At the bottom of the rack was a molded-in plastic stopper. I simply took a hack saw blade and cut off this stopper and reassembled the console. Now the car can be held in first gear. I didn't even have to modify the console. The lever goes past the "2" and into an unlabeled "1". It's like I have a secret gear that no one knows about. (IMG:http://www.frrax.com/rrforum/style_emoticons/default/beerchug.gif)

Matt