I realise what I am about to ask does not take all factors into account;

But as far as Gearbox/diff combos go on a daily driver - what are the options and how much power can they safely handle?

i just put a five speed into mine but put the 4.444 ratio box instead of the 4.111 so shoud be able to handle a little bit more than standard and can handle a little more under load..

but from what i have heard WRX's gearbox's dont like much more than standard power?? didnt believe it myself but that is what i was told by a few workshops..

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straight line racing is only half the fun....
C/Vale represent!!

Stockers - its more the clutch / gearbox / mechanical sympathy combo you look for not really the KW ATW.

94-01 WRX .......3.9 Final Drive ratio gearbox would be the weakest, especially if a heavy duty clutch is put in and you launch by dumping the clutch with no mechanical sympathy. The shock loading on the 2 -3rd gearset will quickly strip 'em. Stick with a standard organic clutch if the car has been tuned, it will act as a fuse.

4.111 Final drive would be the next weakest due to the less torque loading on each gear tooth.

4.444 FD....02+WRX or GC8 STI would be the next up from that with less loading per gear tooth plus and increased gear tooth width compared to 94-01 gearset.

4.444 FD STI RA box then with all of the above plus hardening treatments on the gearset and billet steel selector forks.

The 4.444 Final drive ratio boxes seem to cope with 200+ KW ATW comfortably with sensible driving and no high RPM clutch dumping. Not a lot of sensible drivers appear to have broken em compared to the weak 3.9 WRX boxes.

Drags = get a STI 6 speed or a PPG 5 Spd for $$$$ and reliability

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"You can turn your back on a person, but, never turn your back on a drug. Especially when it's waving a razor-sharp hunting knife in your eye." - Raoul Duke

4.444 handled over 400hp on staces beast stock with a heavy duty organic (stace?), then was sold to a forum member who blew the box within the month i belive due to a 9 puck brass button clucth ^^

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- White 'Bug Eye' STi -

Hrmmm.

Choices....

yes the 5 speed boxes aren't strong like the 6 speeds, but its mostly dependent on how you drive.

I thought the 6 speeds are not well suited to drags due to their ratios?

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I am only an asshole on the internet :)

[SIGPIC][/SIGPIC]

I know Wilmo's old JDM 6 speed out of an STI Forestor had longer ratios that were perfect!!!!

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"You can turn your back on a person, but, never turn your back on a drug. Especially when it's waving a razor-sharp hunting knife in your eye." - Raoul Duke

Yeah he had his tailshaft modded to run on his 3.9 ratio diff i think if im not mistaking . . .

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M POWER

Looking at a set up for about 220kw atw, Daily driver (not too much thrashwork) and I want something that can cope, dont really go to the extreme...