as title, been bugging me for a while what box i have.
using 205/50x16 (standard classic shape size), my car only does 125mph max at 7000rpm!!

any ideas?

to help, at 7000rpm redline in each gear:

roughly:
1st = 30ish
2nd = 50ish
3rd = 70ish
4th = 90ish
5th = 125mph

ian

 

Yikes ! No idea M8, that's even lower than my Ra
The early Ra's have a 'close and low' ratio gear set but ran on 3.9 diffs.
Later ones ran on 4.4 diffs but with higher gear ratios giving similar overall gearing.
Sounds like you may have an Ra type box perhaps with 4.1 diffs ?

 

i know, bl**dy low aint it.

i was just thinking like you mention, that maybe the diffs are lower than they would have orignally been on the box.

thing is, cant find out either, as the box and diffs came out of a previously modded import that was brought over here not too long ago.

god know

lets put it down as bodge gearing
tell you what though, accelerates well

 

You can check the rear diff ratio by counting the turns of the propshaft required to rotate the wheels 1 turn, front ratio is going to be fairly close hopefully

 

lol...should hope so

 

17.8mph per 1k sounds pretty standard for an RA. Typr R is 19.8, STi 4dr is 21.8, Uk 24.8.

Mark.

 

I think you will find it is 4.44:1 which is not a bad thing as you then have the option of 4.11:1 or 3.9:1.
Front diff change is probably a crown wheel and pinion swap only but there are two rear diffs. The "Big Diff" AR180 and "Little Diff" AR160. Options here depend on which one is fitted.
If you want info on geared speeds after a diff change, check your rear diff ratio as Andy suggested and get back to me.
Obviously front and rear diff final drives should be the same unless you have been at Scooby Sport where they fitted 3.9 front and 3.545 rear and it took months to find the cause of poor handling and crap braking on the rear on my STi ver 6 Wagon.
If you want to change ratios I may have some of the bits you need and can tell you what is involved.

[Edited by harvey - 11/15/2002 1:46:23 AM]

 

my standard legacy gearing had 3.9 front, and 3.545 rear, but its got a 1.1 ratio drive somewhere in the gearbox before it feeds to the rear diff...is this different for sti's then?

i still have my diffs, just wondering whether its worth the messing.
im just thinking that when i do a 500m sprint, that it may hit 125max before the line and hold it back etc.

but then again, never done a timed sprint, so will probably try it first.

ian

 

Ian

If you can hit 125 in 500m you will be ahead of me and just behind Mark A !

 

no need to change the box then..lol


ian

 

3.545 with 1.1 stepper gives you 3.9 as near as dam it but the 1.1 step was, I thought, a feature of UK Impreza's. The Jap cars and certainly STi s were all direct drives ie. 1:1 and not 1.1:1
For sprints the lower gearing is probably preferable providing you can change gear quick enough. At some stage there will come a point where with more power it is quicker to do a 0-60 or 0-100 sprint with one less gear change. ie 2 gears to 60 mph instead of 3 and 3 gears to 100 mph instead of 4 but I would guess it takes a good bit more power than standard.

 

Agree with you on that one Harvey. The extra low Ra gearing makes a standard car feel fast but once you get a bit more power out of them it's just a blur of gearshifts
From a full bore standing start I'm in 5th gear in just over 8 seconds, now if you consider that a gearchange can take anywhere from 0.3 to 0.8 seconds then in that 8 second dash I'm off the power for approx 2 seconds !!!
One reason why cars with dog boxes are so quick, their shifts take less than 1/2 that time.