its an americian ebay no name jobbie. and it seems to have some inaccurately machined parts. the sealing ring provided didnt fit in the groove in the flange, was about a mil too big. so i machined off a mil and it fits in the groove fine now. but is still bloody blowing!

i think the rings not deep enough so wanted to try another one from a proper company that i know would have machined it properly, as far as im aware sealing rings are the same design/size on all applications (as long as its a 38mm one in my case)

it boosts fine in all gears but first. because first gears so short its not got enough time to build up more than 5 psi with the blowing