6 speed conversion advice for V5 Type R
 

My engine build is near complete which is a 2.1 stroker with JDM STI avcs heads and a MD321T+ twin entry turbo.

My first thought was to run in the engine with the stock 5 speed gearbox but the season is pretty much over already so I thought I could just as well buy and fit the 6 speed when the engine is out so I don't have to take things apart again.

So, the question is which 6 speed DCCD gearbox would be the best to get? Did the synchros get better in 2006? And which torque distribution is better for handling? Maybe the 41/59 distribution would be better for a 450-475 BHP classic. And would the JDM sti ratios be too short at that power level or just fine? I loved how lively it felt with the stock 5 speed at 370 bhp but maybe there would too much shifting all the time with 100 bhp more.

What do I need to get for it to work in my Type R with the R180? Gearbox, prop, rear diff, starter?

Any recommended place to buy? Would need to be shipped to Sweden so not comfortable buying from a private seller in this case.

I am in exactly the same boat. Currently at 360bhp and dont want to push the standard 5 speed any further!

But according to my engine builder, the Hawkeye DCCD box is the one to have. I did not ask any questions about why as I trust their advise 100%.

Will be watching this thread with interest!

The hawk boxes came with carbon synchro and have the best spread of ratios once you're above 450bhp.

gearbox, matching r180 diff, prop and a clutch to match your power goals. matty @ mb would be a good place to start

I've had a 6 speed conversion on my V6 STi wagon using UK Hawkeye 2006 DCCD box and R180 diff, needed RCM stub axles for gearbox and rear hubs from a 2001 bug eye STi due to not wanting to go wide track. . . .all works very nicely, just running my 2.1 stroker in. When that's done should be around 450ish bhp and will have Syvecs running the DCCD too :)

So hawkeye boxes are to prefer. Then it's mostly a question if you want the JDM or UK/EU gear ratios. I really do love the tight ratios of the JDM boxes though even if it probably means slower acceleration times at this level.

You have 3 choices.
U.K. And jdm Dccd boxes are same ratio apart from 5-6th is longer in a uk box.
The hawk uk box is longer from 2-6th, ideal for drag racing. (Not 100% sure on the jdm hawk box, presume it's same as the normal jdm box?)
All depends on use, for track, deffo jdm, for normal mixed driving and odd motorway then uk as 5th-6th won't be at high revs like the jdm for motorway driving to events etc if road legal car.
Or hawk would be OK if you don't like changing gear too quick lol as with 6 speed boxes you go through the gears quick if running reasonable power.

Are you sure? I thought the JDM DCCD 6 speed had shorter 1-4 and a longer 5 and 6?

Pretty sure yes, I remember banny telling me a while back when i was deciding on box, the jdm is limited to 112mph so wouldn't have longer 5-6th, uk box has longer 5-6th to allow better motorway cruising

Busta is correct, JDM is shorter 5th and 6th and the ratios are more evenly spread all the way through. 6th on a jdm at 70mph is roughly about 3200rpm and on a UK its about 2700-2800rpm.