I have an automatic, and for drag racing i dont know what gears i should use.

From a stop, what is the fastest way to get to 100 mph?......starting in drive, starting in overdrive, or shifting from 1st to 2nd to drive and then overdrive?

Please let me know what you think.
Thanks.

 

Your best bet is to just start in drive. You will never be able to shift faster than the tranny will. So don't bother with starting in 1st and shifting to 2nd,etc. If you only plan to run up to 100mph you shouldn't have to shift into OD. Also as long as you can get traction try to load up the suspension with the brake on(stall the car up) and then stomp the gas at the same time you release the brake apon launch. That "should" give you the best launch, traction permitting.

 

A good all around gear is a 373....in my opinion....

 

.....

Buy a 4th gen

 

Moving to the drag racing forum...

 

At what MPH would I eventually need to shift to overdrive?

 

Never .

With a relatively stock car, you won't go that fast. I don't know how 3rd-gens with the TPI engines run in the 1/4, but I guess you'd probably cross the line around ~95 - 100 mph. Check out this chart (and bookmark that! ). Select '98 F-body A4 from the list (your transmission uses the same ratios) and just change the gear ratio part and your tires (if they're different) and see what #'s you get. Even with 4.10 gears, 3rd gear will top out around ~112 mph, and you'll have to have a lot done to your car to hit that speed. Then, if you ARE making enough power to run over ~110, you'll be into the 12's, and at that point, your engine will probably rev higher than 6000 RPM, so then that will increase your speed per gear, and if you run taller tires, you can run even faster.

Basically, what I'm saying is that by playing with gear and tire size combos, you can determine the maximum speed you can go in 3rd gear, without running into 4th (OD).

For a street/strip car, 3.42's are good, as well as 3.73's. With a 3.42, you got a lot of room to play in 3rd gear (upto ~135 mph!) and they're nice for cruising on the street too.

In terms of shifting, the 700-R4 uses a manual valve body I think? so you CAN manually shift them and decide what RPM to shift at. OR, leave it in 3rd (Drive) .

 

Since it's a 700R4, leaving it in drive is your best bet. With an electronic (4L60E), I start in 1st and move through the gears myself. It's always worked best for me when I had a tranny that shifted itself.

 

Just outside my town there's a huge straight stretch, maybe 3 miles long.......with no houses or anything around. For when i race on that, when should I shift to overdrive?

 

I would have said the exact opposite. The electronically controlled trannies respond really slow to "manual" shifts, whereas trannies with manual valve body respond more instantaneously IMO. If you're trying for consistency, it's too hard to always shift the 4L60E at the exact same RPM in advance (because there's about a ~1 - 2 second delay). I know that with my '81 and its TH350, it would shift when I shifted it, and I think the 700-R4 (aka 4L60) would work the same.

.....however, all that being said, as long as the shift points are set at a good engine RPM, then there's no benefit to manually shifting, so you might as well put it in Drive and just go for it! Especially if you want to be consistent.

 

Once you run out of 3rd gear?! I guess just start with the shifter in OD and leave it there. As long as your foot is on the floor, it'll shift when it's time, as long as the car maxes out 3rd.

 

If you're trying to nail the shifts, then yes, I'd agree. If I'm not mistaken (been a while since I messed with LT1 Edit), there are different tables for normal, perfomance and manual shifts. Normal is if it's left in OD, performance if the button is on and manual if it's started in 1st. I usually hit the shift a good 500rpm before it's supposed to and it works perfect. I did it with my '95 when it had an A4 and I did it on a friend's '02 Z (A4) and cut better times than him everytime.

 

not true, the 700r4 in the 3rd gens wont let the trans go into OD at WOT so when it bangs the limiter let up real qwik then slam your foot back down