I currently run a DX tranny with my boosted z6, I own a EX tranny with a bad 3-4 syncro that i'll be rebuilding at school and also putting in an OBX LSD. I had the thought of putting in the taller DX 1st gear in the EX tranny as I feel this would help with my 60ft times being longer than the EX 1st gear.

My first question is, are these gears even interchangeable? and my second question is will this additional work be worth the payoff or even make sense? Lastly, should I just STFU and run the LSD EX tranny and leave the gear alone?

 

the DX and EX 1st gears are the same, Aren't they?
It's the final drive thats different?
I could be wrong but thats what I thought.

Edit: yeah the calculator at zealautowerks shows the 1st gear is the same, 2nd and 3rd are different. 4th and 5th the same.
And of course the final drive is different.
http://www.zealautowerks.com/transcalc.php

 

1st and 2nd gear are integral parts of one of the shafts (can't remember if it's main or counter) inside the transmission. You have to change them together and you will in fact be changing the shaft. However, have you done your research? I'm about 99.9% sure that 1st and 2nd are the same ratios in all the D series FWD transmissions.

 

**** guys, thanx..i didn't realize this, i read the other night that the DX tranny was better for 60ft times..i thought it was because of the 1st gear, but i guess not.

 

All single cam trannies are long as hell anyway...

 

1st are all the same then the rest ar different.

I have a SI tranny with
3.25 1st
1.9 2nd
1.346 3rd
1.033 4th
.702 5th

Im making 300whp in my d16y8.

I had a SI trnny in my car stock. Then i swapped in the SI tranny with the ZC 3rd and 4th and the difference from 2nd to 3rd is noticable but its the 4th gear shift.

I raced a few friends of mine that i used to pull a bit when i clicked in 4th. Now when i hit 4th i pull instantly 5-6 cars.

I used to have a DX tranny in this car with the same power and **** it was way to long. I would race some cars and they would switch 3 gears and id still be in 3rd lol.

http://www.fatboyraceworks.com/gears...raph&Compare=1

 

thanx for this info man, much appreciated!

 

only difference is the 4.25fd in the si and the size of diff bearings. I have two dx trans with si in my garage right now.