Is there differencies between central viscous coupler in turbo UK and STi 3-6?

General design should be the same, although the drop gears in the JDM cars will be 1:1 instead of 1.1:1 on the UK/Euro.

Not sure whether there are any detail design differences between the internal components on the phase 1 and phase 2 (MY99 onwards) gearboxes though. The casing is slightly different, so it's possible that the internals will be too.

Thanks,

but Im interested in differencies between lock characteristic of viscous coupler. Heard that UK turbo has 4 kg/m, then which parameters has STi?

I'd heard 12kg/cm for Euro and 20 for STi's. Some info on MRT site.

Richard

Im sure you are wrong. 20kg is very special viscous coupler. If you have one installed you cannot turn :-)
12 kg is more better upgrade for normal driving. But it is not basic viscous coupler in Sti.

Hhm - there's some for sale at MRT, and (IIRC) an autospeed article about swapping out standard with STi. They measured both from memory. Not saying I'm right, but that's what I remember :)

Richard