Hey all Is anyone here running an n/a 5spd box (MF5) on a turbo motor? If so what clutch are you using, and how is the gearbox holding up? I'd imagine that as long as you launched it nicely and didnt do any flat shifting, it would hold the power of a stock motor for ages. Can anyone confirm or deny this? Thanks.

im currently running a NA 5spd behind the turbo motr, using a 5 way brass button clutch, 1500 pressure plate, runs wickid no slippage and i give the car alot of S*** aswell, it pulled mid 14's down quarter and hasnt stuffed up or anything, been behind it for over 6 months now. i also launch it of the line hard as and and do some flat shifting now and then.

lol - makes me wanna turbz mine!

well i honestly thought that the n/a box could take a fair beating, i think my 160k kms box will be fine with a turbo motor on 10psi... so i may swap the motors on my two cars. love the turbo, sick of the auto, only done 120kms in the turbo too.

anyone else want to comment?

PM morepsi Cheers.

A quick comment... Mate's VL turbo runs an n/a 5 speed and he's onto his third box. The first one had 200,000km, the second was rebuilt cost $700 (ripped off) and lasted 3 months. Onto third now. I just don't know why he won't put a turbo 5spd in it. ???

i have heard from a pretty reliable source that the RB20DET 5 speed boxes will take about 200rwkw without hard line launches before the gearsets destroy themselves. this box is pretty much identical to the MF5 in terms of strength, but has twin ring synchros on a few extra gears. so i'd say that if you treated it okay and didn't dump the clutch hard off the line too much, or flat shift with big boost you'd be okay.

already spoken to morepsi. and dont worry, if i go ahead with this, it'll get changed to an mx7 or r33 box as soon as it breaks!

It all depends on how you treat it. I know of 2 guys who did the conversion with NA boxs and had no trouble at all. One used to cane the **** out of his and only ever really slipped the clutch occasionally.

I have an n/a 5sp running on 12psi, it was in the car when I got it 12mth's ago now so I dont know the age or condition of the box, I have gave it quite a hard time but its still just the same as when I got it, not sure what clutch is in it but it dosen't slip at all, the only thing I find is 1st gear is a little too low.

Well I'd say at the moment that my old n/a box 'felt' as though it would last, now I'm running an mx7 and its not in the best condition, I'm going to get it fixed up before I put a turbo in front of it.. The last thing I want is a blown mx7