does any one know how much horse power that the sunny 5 speed gearbox is able to cope with e.g max. hp. and is it going to handle a lot of burnouts i.e. is it
a strong gearbox

dont waste it on burnouts, get a $20 4 speed and fry with that.
as for max hp, dunno.
linc.

Well, i just put the 5 speed behind my 150hp A14 and i am expecting it to break in no time after a couple of big burnouts. Its no stronger than the 4 speeds and i've broken quite a few
of them with a mildly worked A15. The only reason i have the 5 speed atm is just to see if it works basically! I havent used it in like 2 years so it'll be interesting to see it behind
150hp. So i now have a garage full of 4 speeds ready to break :) cya

Scott
Davo

In my experience the A series 5 speeds are stronger than the 4 speeds. The original 4 spd 1200 box is very weak and is prone to losing teeth easily. The 120Y models onwards
had wider teeth and were stronger. The trick over here years ago was to fit 180B gear clusters into the 4 speed housings. I've never done it myself but understand it was a
straightforward conversion.

You're right about the gearboxes. Earlier A-Series boxes had bushings instead of bearings in some critical places. Also the journals for the bushings did not have the
reinforced design, which was bigger and looked much tougher. I guess this is the 120Y box stirlingmac is talking about.
Unfortunately, I can't remember the external differences to aid a wouldbe 2nd hand A Series gearbox hunter.