What would happen in the quarter mile if you changed the gearing of the transmission from stock to a 2.84 or 3.06 first gear? Would the quicker rise in rpms force a shift into overdrive in the quarter mile or improve your time? Would it make for a faster street car? How would it affect spoolup on a larger turbo?
Gearing and the 1/4 mile
- Thread starter CopGn
- Start date
I have problems sticking to track with stock gears ...
I think that the shift COULD make you go into OD, depends on a lot of things.. you dont want it to go into OD. Overall if you can stick it, it would improve your 60' I would think. Kinda wondering the same myself now that you brought it up.
I think that the shift COULD make you go into OD, depends on a lot of things.. you dont want it to go into OD. Overall if you can stick it, it would improve your 60' I would think. Kinda wondering the same myself now that you brought it up.
slamming 6
Drag Master
- Joined
- Jul 21, 2003
It would'nt change the shift into overdrive as for a better time you need the car to hook real hard to have it work or its wheel spin city good luck AL.
BobbyBuick
Well-Known Member
- Joined
- May 24, 2001
When I first built my car my 1-2 shift valve was stuck.I didnt notice it the first few times I raced it as I was preoccupied ((hanging on)
Leaving in 2nd gear the car went 10.80s off the trailer.after getting 1st back it 60" better and went about a 1/10 faster.that is when I know all the talk about the 1st gear ratio of a 400 VS 200 was just that .TALK
Leaving in 2nd gear the car went 10.80s off the trailer.after getting 1st back it 60" better and went about a 1/10 faster.that is when I know all the talk about the 1st gear ratio of a 400 VS 200 was just that .TALK
I can't speek for amyone else, but I can tell you that my car w/stock gearing already rises in rpm too fast. As soon as I release the brake and mash the throttle, i'm shifting into 2nd. This is with a 5psi launch and manually shifting. Sometimes, I wish I could start off in 2nd because 1st doesn't last 60ft.
strikeeagle
New Member
- Joined
- Jun 6, 2001
Ideally, you'd have infinitely variable transmission gearing, to keep the car at its torque peak at all times, an no rear end gearing. Ever see one of those cone transmissions with the belts? Now that's the ticket!
There was a guy on one of the boards (this one?) with a white T who used insane rear gears and of course shifted into OD. He was an NHRA Stocker, I believe, and swore by his approach.
Of course, you could use a lot more gear in the 1/8th than in the 1/4. And a lot more boost.
TRs have the extra element of the turbocharger, and the load it likes, which just complicates life.
There was a guy on one of the boards (this one?) with a white T who used insane rear gears and of course shifted into OD. He was an NHRA Stocker, I believe, and swore by his approach.
Of course, you could use a lot more gear in the 1/8th than in the 1/4. And a lot more boost.
TRs have the extra element of the turbocharger, and the load it likes, which just complicates life.
strikeeagle
New Member
- Joined
- Jun 6, 2001
Well, if you believe the problem with a higher numerical rear end gear is that it doesn't load the turbo, that implies the turbo likes less torque multiplication...
strikeeagle
New Member
- Joined
- Jun 6, 2001
Overall gearing is the tranny gear ratio times the rear end gear ratio. Raise either and the motor spins faster and the turbo load DECREASES, or so I've been led to believe.
If you change the gearing in the trans you can spread the gearing to far. On a 700R4-3.08 first gear and a 3500 stall the car came off the line like a rocket butfell on its face after the 1-2 shift. It has to much spread. The best gearing is a close ratio like an old m22 rock crusher,get the rpms up then keep them there.
Here is some thing that I have been thinking about. TTA's run 3.23 rear gears and GN's run 3.43's. Alot of TTA guys 60' right in there with the GN guys. My TTA weighs #3800 with me in it. I have 3.25 gears and 28x9 slicks. I can 60' in the 1.4's leaving at 8 to 10 psi off of the foot brake with an a/c 9" 3200 n/l. I really think that making my car "grunt" against the gear and using the torque that this motor loves to make is why I do well. I would think that any gear change within reason that would make the motor "work harder" to get the car out of the hole may work.
On my old set up I barrowed a set of 29.5 x 9 slicks once off of my dad. That was the best every thing my car ever did on the old set up (60', 1/8 and 1/4 et's and mph's). This might not be the case for every one because I grab O.D a few hundred feet from the end of the track d/t my stock cam and head's lower shift points and a non lock up convertor.
HTH: Jason
On my old set up I barrowed a set of 29.5 x 9 slicks once off of my dad. That was the best every thing my car ever did on the old set up (60', 1/8 and 1/4 et's and mph's). This might not be the case for every one because I grab O.D a few hundred feet from the end of the track d/t my stock cam and head's lower shift points and a non lock up convertor.
HTH: Jason
