How much BHP will a standard 4x4 box take ???? Looking to upgrade my 4x4 Cossy to 380 BHP....Who are the best people to speak to and how much....Thanks All Wilmot ( Liege-Belgium)

 

I’ve heard via the grape vine that the standard box will not take much more than 350BHP. I’m running 375BHP on my standard box, and all is OK so far. But saying that, I don’t do any silly launches, and I do have a big tooth Quaife box sitting in the garage for when I get round to fitting it. I got all my parts from Graham Goode Racing for my 375BHP conversion, and did all the work myself. Once finished, I took it to a rolling road for setup to the check the fuelling/boost etc. I’m very happy with the way the car performs. Every body seems to have their own preferred tuners, so I’m sure someone will recommend another tuner. As for cost, it’s very difficult for me say, as I did a lot more work than what was necessary for the 375BHP conversion. I had the engine re-bored new pistons, crank reground etc. etc.

Have a look around the web site : - www.grahamgoode.com

Hope this helps.

Cheers
John

 

does bhp brake the gearbox or the torque...

 

My car will be set-up by Stu....Engine output 380ish.........And thanks Boys for your help...........

 

its low rpm and high torque that kills the gearbox

if you do threat the gearbox nice i think it can handle 380bhp fine.
Just keep it high on revs, dont kick the clutch, dont do any fast (crunch) gearchanges, use high quality oil.

But again keeping it high on revs on a road going car is not that easy..
either way it is not bulletproof.

 

Read somewhere that someone has fitted longer 4th and 5th gears into there Cossy Box..............I understand this will help on a run....does anyone have any views on this and who carried out this modification...sounds like a good idea for 5th, but not sure about 4th.. Thanks 'Wilmot' (Liege-Belgium)