Hey, i am debated on which final drive to use for my tranny. What I want to know is if you guys think that the ats would be too low for drag racing with a 9100 rpm rev limit. He have got all of the max speeds for each gear with the jdm and ats, so tell me what you think. This is shifting at 9100 rpms

JDM ATS
3.230.....40.30...39.13
2.105.....61.84...60.04
1.458.....89.29...86.68
1.107.....117.60..114.16

the end of 4th doesn't really matter because I will never be that fast, but the jdm with 9100 is very similar to stock at 8500 rpm. Let me know what you guys think.

 

has anyone had a jdm final drive and then switched to an ats??

 

If you really want to know then contact Rodney. He has the ATS currently and had both the JDM and USDM installed prior. I personally have been in his car and can say that it pulls like Hell, "Hell being a good term."

On the other hand he also has heavily modded his eingine with Toda B's and a remapped ECU and higher redline. So I'm not sure how it will work for you.

I will however say that using an R for drag and 1/4 mile is just silly. Now replacing the Final for track and Auto-X is a good move and one that I'm also planning for next spring. Buts thats just my opinion. and I'm sure to you that it doesn't count for Sh*t.

Good luck,

A.


[Modified by 1GreyTeg, 8:20 PM 11/14/2001]

 

i'll try to get a hold of rodney.

I do agree that the type r was not made for drag racing, but I do both autocross and drag. One major problem that us Utah boys have is that the only track we have out here is a drag strip. They are suppose to be making a road course track, but that won't be done for at least another year, so I just have to race in whatever is available which is mostly drag racing.

 

ok, here is my humble opinion. with my limited 1/4 mile experience (although i was very consistent, .2 sec variation over 7 runs...) i found that with my jdm final, i was shifting into fourth and crossing the traps at about 7300k rpm. since then i have done a spec B topend, and gone through my tranny a bit more (ATS lsd, ATS 4.93, Toda flywheel etc) in my best educated opinion, the ATS 4.93 in my car will allow me to pass the traps at upwords of 8k infourth, perhaps a tad higher. this would allow my car to get in it's powerband earlier, therfore increasing trap speed. with your extended rpm, you can take advantage of a lower gear. i think it is a worthwhile mod most definatley.
i know the specs between the jdm 4.78 and ATS 4.93 are very minimal. but after driving with the 4.78 for 7k miles then swapping to the 4.93, i can attest that spec don't mean ****! the 4.93 totally woke my car up, moreso then the specs would imply. i am kicking myself in the *** for not doing it in the first place. also, my car is kind of heavy, 2608 with my fat ***. if you a 1/4 guy, you wouldn't mind gutting the car, which of course will make you faster.


[Modified by rodney, 8:11 AM 11/15/2001]

 

Hey Rodney, I read your signature, but since I have an Si hatch with the R swap and such, I'm curious about the 1/4 mile times you turned. I'm not a big 1/4 mile guy either, but I did go once to see what mine would turn. My car weighed in at 2280 w/o me, and I weigh 150lbs., so my race weight was 2430. FYI I turned a 13.9 @ 100.97mph with stock motor and street tires, full interior, etc. Not bragging at all, just letting you know how a car with a similiar set-up ran w/o cams and the final drive.

You pretty much have the same set-up I'm goping for. After my ATS is in, the next project will be the Spec Bs or MAYBE the JUN 3s, but not decided yet.

LATER.

 

regarding my 1/4 time, it wasn't impressive, when i run again and i find that it is a worthwhile time, i will post it. i had a plethora of problems, none of which i will bother posting because i will get a slew of responses stating "why didn't you..." or "you shoulda...."