The AUSubaru.com.au Forums

I have got two bits the same to compare and noticed the turbo pipe I bought on ebay has a 40mm hole in the turbo mount plate whereas the same hole on the turbo pipe I oulled off my GLAT (looks to be an later fit import) has a 45 mm hole ...hmmm any knowledge on the subject ?

Yes the Oz spec one will have a smaller hole due to the shittier fuel we had when they where released they choked the turbo. Tha Japs got a bigger hole

uh huh, same turbo just smaller hole, do you understand the different performance between the two pipe pole sizes, like torquier or freer revving etc ?

i honestly can say i have noted any difference in the pipes by seat of the pants testing

I found the Jap ones to have the smaller hole, I think it was simply to increase exhaust gas speed slightly to help bring on boost sooner in the rev range due to their large amount of city/traffic driving. Where the Japs seem to think all we have is highways or something, take a look at the RS turbo for example with the tall diff gears and the VF12 turbo.

I was thinking smaller hole would do that - might be the option to try

WHEN I get my 'nother motor...cough, cough....chris ? (says he in a small voice, knowing you must be flat out with your business at the mo')

Yep mine bad Subaman is correct