The V8 Owners Forum -

I have a friend who owns a rod with a 4.6 ltr race tuned RV8 Circa 300 BHP(cross bolted block 300 degree cam etc etc) He didn't build the car but believes it has a Borg Warner auto box in it which he has had rebuilt.
I know nothing about auto box's but apparently if he stands on the loud pedal hard enough the box slips a bit like the clutch slipping in a manual box.

He wants to keep the car auto and needs advice on which auto gearbox would be best suited to an RV8 with this sort of power. He does understand he may need to get either an adapter plate or custom bellhousing made.

Advice please

Start here, http://www.classicroverforum.com/viewto ... f=1&t=8515 then browse the place for info. There's LOTS of it there.

I'm not surprised that any of the BW boxes would cry enough transmitting that sort of power. The ZF4HP22 bolts straight on to the Rover V8, (from the Range/Land Rover, as well as 2WD versions elsewhere) and can be uprated to HP24 spec which would be a better bet, although I'm not sure how they can take without problems, and the earliest Range Rovers used the Torque/Loadflite so that bolts straight up too, you just need to convert it to 2WD, and there must be loads of tuning/upgrade parts available for those boxes. Both fairly easily available, and to do.
I'm sure others will have suggestions of good boxes that can be made to fit the engine with adaptors, but those two can be fitted without the need to do that.
Put that poor BW out of it's misery as soon as you can.

It's not the power output of the engine you need to know, but the maximum torque. That is what limits a box. Unless it's been supercharged etc or running nitrous, I doubt it's much higher than a standard engine.

The ZF 4HP was fitted to the 4.6, so a relatively easy conversion, if there is space. The transfer box gets replaced by a tail from a RWD using this box - BMW, Jag, etc. Or even from a Sherpa V8 if you can find one.

However, many standard transmissions can be uprated to cope with higher torque. But you'd need to know which one you have.

Thanks to all
This is just the sort of info I was looking for, I will pass the info on.

Keith