c1teg

hey guys i have a 99 civic si with a ls vtec makin 185whp and 125wht and a 98 spec itr tranny with the following mods.

1st Gear 3.23 -stock 98 jdm itr
2nd Gear 2.105 - stock 98 jdm itr
3rd Gear 1.69 ATS
4th Gear 1.269 ATS
ls 5th Gear to keep the revs down on the highway
Final Drive 4.92 ATS

it works pretty well, only drops about 1500 rpm between shifts. i had it to the track and my best run was a 14.5 at 94 mph, 2.o 60ft with 22" m/t slicks but im on the limiter in 4th gear at about 100-150 feet before the line. i moved my rev limiter from 9200 up to 9500 but still isnt enough. im goin to be makin some changes to my motor this winter i dont think i would fit a much bigger slick on my car.

so im thinkin im either goin to change the ats 3rd and 4th and ls 5th for the stock itr 3rd and 4th and gsr 5th with 4.92 fd

or switch the 4.92 back to the stock 4.78 and use the ats 3rd, 4th and 5th.

for motor changes im gonna go from 81.5mm to 84mm bore, blueprint stg 2 cams to skunk2 stg 2 and 11.0 comp to12.5. just wonderin wat u guys think will work the best for a tranny combo

thanks in advance

fv8s

This should probably be in the transmission/ drivetrain section of the forum

unusual71

longer first gear and shorter final drive, the rest looks ok

c1teg

so ur thinkin like a b16 first gear with a 4.78 fd

unusual71

you need an aftermarket first gear all Bseries first gears have the ratio of 3.23:1.
but yeah that will probably make the car slightly more useable at the higher tq level.
i would personally go with a 4.4 final but if you only have the 4.7 thats not bad

c1teg

yes i thought all the honda 1st gears were all the same. i cameup with this on a gearing website, this is with a 22" slick and 9200 rpm

c1teg

im kinda leanin towards the 4.9 final drive and stock itr gears, that should get me across the line at almost the end of 4th with the extra power

PyroProblem

Id put the stock 4.7 FD back in if it were me. With the extra TQ going to 84mm, I dont think its gonna hurt you one bit.
Arent the 4.9 FD more for autocrossing?

c1teg

^^^^ seems like i get a better mph gain with the stock ITR gears though, i would only gain 2 more mph with the 4.7 fd and thats not enough i dont think

PyroProblem

I think youll gain alot more than that just by stepping up to a 2L...When I went from 1.8 to 2.0, it was like a night and day difference.

c1teg

so do u mean the stock fd and stock gears or stock fd and ats gears. from ur pm im assuming stock fd and gears. only difference between the two was the 20" and 22" slick i have

TheShodan

iTrader: (14)

Circuit/Road racing. AutoX, you don't even get to the sweet spot of the gearing on 99% of the "cone" courses.

4.929 is fine with what he has for maximum acceleration and torque multipier. I use one myself, but kept the B16 2nd-4th gears, with LS 5th gear.

TheShodan

iTrader: (14)

that's if you're drag racing. a little different than what the gears were intended for

PyroProblem

Yeah I was on stock gears and a stock 4.7 FD on 20 inch slicks. I would cross the line right at redline in 4th gear. My engine was a little tired and had some blowby but still managed mid 13's @100mph

c1teg

ya i dont do any road racing, its just a weekend warrior and i make a few visits to the strip a summer and a few car shows. think im gonna try some stock gears and stick with the 22'' slick

c1teg

anyone else got any suggestions

PyroProblem

Id finish the rebuild first, run it, and then re-assess the gearing afterwards.
The increased power and torque might change your gearing needs.

all-mtr-teg

I like this calculator, guestimate what your trap speed will be, and choose a setup that will put 4th just above your estimated trap speed.

http://www.fatboyraceworks.com/gears/

^^^^^^

JayWest

try 23" slicks, keep everything in your tranny the same except for swapping out the 4th gear to a b16 4th

should put you right around 117mph @ 9200