B-Series Gearbox ratio Problem

[chris2000]

Hope you guys can help..

I'm running ATS 1-5 close ratio gears with stock GSR 4.4 Final drive.

I'm running out off rev in the SIC long straights coz i got to rev on 5th gear till about 9000rpm. I find it very stressful for the engine and at times in other corners i have to hold the 4th gear at high revs too cause changing to 5th gear just too troublesome coz got to downshift again in spilt seconds.

I heard that there is a lower FD from another B-series gearbox that I can mod into my current gearbox, something like 4.2+. Anyone know how can I get hold of these and whether it will really fit my GSR gearbox with no problems??

Please help. Thanks..

 

[speedo-eg]

nood question here.... will 1-3 onli close ratio is better for circuit ? or close ratio is not good for circuit ? thanx.. :P

 

[basahboy]

nood question here.... will 1-3 onli close ratio is better for circuit ? or close ratio is not good for circuit ? thanx.. :P

enclosed here are my calculations on GR based on either FD 4.875 or FD 4.4 with/without FD 4.925 or CR 1 to 3...pls make your own assumptions...the calculation is more for a guide...

 

[djlv_vtec]

close ratio is good if u can find a track like Batu 3,Shah Alam..short straight,a lot of corners..it will be superb!
it depend on what track u run to perform..

 

[Jasper]

1 2 leave standard change 3,4,5 and 4.533 final should able to hold 5th gear on long strech .5th 1.033

 

[hattech-v]

jasper, 4.533 fd got what brand?

 

[Jasper]

os giken

 

[hattech-v]

jasper, what if couple 4.785 fd with ats 345?
some said kenot but on of my fren did it...4.785 with ats 3 and 4 only... 5th using std ratio....
but definitely the 5th gear like unjustice...

 

[Jasper]

can why cannot ,it all depends one how you going to drive that car only mah

 

[HanafyEG]

4.785 plus 345 ats can be use..but it would stress the engine i think..no doubt pick up would be syok..hehe, there are cases where engine blow up because of too short ratios..

 

[chris2000]

Hi guys..

My car is running out of rev even at 4.4FD, so if to use OS 4.533FD or Type R 4.785 will be worse.

ATS3-5 with 4.4 I only can get about 200km/hr at 9000rpm. If OS 4.533FD i think only 190+km/h and 4.785 will only be 180+km/h.

I need to get more top speed and not lower speed.

Anyone got any idea what OEM or aftermarket that produce final drive from 4.0 to 4.3 for B18c GSR gearbox??

 

[J101]

hi there chris,
probably the best option is to change your individual gears. i assume u were hitting top speed with the engine revving hard at the front straight. since OS Giken are from ATS, i would reckon that ATS might have low FD for your hydraulic gearbox. most of the oldschool ones are low but you have to mod your gearbox to fix it, probably it'll be a hassle.

 

[HanafyEG]

os giken have 4.2 final drive...n1 also selling used 4.2 final drive original honda

 

[hattech-v]

oem 4.2final drive for honda i think only can fit to small v gbox.. correct me..

 

[chris2000]

Thanks guys,

I just check OS Website and found that they have 4.267FD. Anyone know who in KL might have these in stock used or new?

One question anyone has any formula that i can calculate what my top speed will be with this 4.267FD?

Can the Honda OEM 4.2FD fit in the B18c GSR gearbox with no problem?

 

[J101]

quaife
--------
http://www.quaifeamerica.com
go to download section

houseman
-------------
http://www.housemanautosport.com/ratio calculator_files/gearcalculator.htm

 

[chris2000]

Thanks guys

The Quaife calculator rocks man!!

Found the OS 4.267 FD fits into what i want giving 6.5km/h more at 9000 rpm or same top speed at about 300rpm less. Thats all i need.

Now, who knows where to get OS Giken Final Drive in KL??

 

[J101]

i dont think its available off the shelf at the moment. if you need it urgently maybe you can try singapore. this sort of FD are among the fav for high hp vtecturbo.

 

[HanafyEG]

yeah ur rite j101..hehehe...

 

[chris2000]

Oh, this FD normally use in Vtec turbo? But mine NA.. Just that my gear ratios are short and i'm running out of revs and i feel i'm stressing out my B18c too much in sepang straight.

Any idea or contacts in Singapore that carries OS products?