Hi everyone, looking for a bit of subaru trivia.

I know the uk and jap 6-speed gearboxes are different, but can anyone tell me how different they are with regards to speed achievable in each gear.

I have a classic sti and i'm looking to convert to a six speed

thanks

 

jap are shorter ratios , uk are better option still changing gear all the time though .dont know ratios off my head but do a search and you will find.

 

if you go for the UK 6 speed you'll have to start changing diffs and drive shafts.

As yours is a Jap STI I would go for a Jap six speed as far as I know its a straight swap so you'd just need the box itself, linkage and a propshaft from an auto classic.

I have the UK 6 speed on mine and its made the car for me.

Hope that helps

Daz

 

Cheers mate, what speeds roughly do you achieve in each gear with the uk box.

Thanks again

 

Why do you need a Propshaft from an Auto Classic?? Mine was fitted using the 6 Speed Prop.
I didn't like my 6 speed at first, takes a bit of getting used to.

 

The 6th gear in a JDM Box is 0.842. which is smaller than the 5th in a UK BOX!!

If the final drive is the same that means you will be hitting the limiter in 6th at 150MPH with the jdm box, MY old 04 STI hit 197 mph on the rollers in 6th., so theres quite alot of difference.

 

Its actually about the same, my JDM Spec C could do approx 170mph, my classic uk turbo could to 167mph, new cars have different ratio's but the Jap ones should still be slightly above the uk ones, and closer ratio's means better accelleration
Oh and the JDM boxes are stronger than the UK ones just to let you know

Tony

 

Both the automatic 5 speed and 6 speed front propshafts sections are shorter than the manual 5 speed propshaft due to both gearboxs being slightly longer. Either propshaft will work but I fitted an automatic propshaft due to not having the 6 speed propshaft included when I purchased the gearbox.

 

how much are the 6 speeds and where is the best place to purchase one from with all necessary parts for the conversion?

 

why are the jdm stronger than the uk box ?
what goes wrong with them ?

 

UK & JDM 6sp boxs have exactly the same ratio's from 1st to 4th. 5th, 6th & final drive are slightly different, with the JDM having slightly shorter ratio's in those area's.

Theorectical top speed on a JDM 6sp with 18" wheels @ 8k rpm would be 182mph. For a UK 6sp with 18" wheels @ 8k rpm would be just over 200mph.

Regards,
Shaun.

 

Also, a jap 6 speed into a classic will need the rear diff too. 3.9 rear diffs aren't usually the standard on classic STI's

 

Jap boxes dont have cheap plastic parts in them plus JDM cars have more torque/bhp as standard, but yes, the JDM boxes are stronger though the gearsets are the same (its all the other bits)

Tony