Standard auto box abilities

Its said the standard automatic box is capable of taking 550bhp. Is anyone nunning this or close to on an auto? how is it coping?

the reason im asking is so i know what i can SAFELY do. Im pushing 440 now but theres a desease called 'i-want-more'

what you guys think? can anyone speak from experience?

p.s i know 6sp man would be better for more power but i like the gt style cruising from an auto.

Dan

It'll be the torque that killls the box but think 550 hp and the torque that'll come with that is possibly right on a stock autobox's limit.

Fit another cooler to it and don't rag it too much and it'll probably last a while

Its said the standard automatic box is capable of taking 550bhp. Is anyone nunning this or close to on an auto? how is it coping?

 

the reason im asking is so i know what i can SAFELY do. Im pushing 440 now but theres a desease called 'i-want-more'

 

what you guys think? can anyone speak from experience?

 

 

p.s i know 6sp man would be better for more power but i like the gt style cruising from an auto.

 

Dan

I would say it depends on how old / worn the clutches and brake bands are. Does it flair between 2nd and 3rd?

I've been looking at accumulator shim mods and line pressure tweaks for the a340e. The TT has extra solenoids which IIRC are for accumulator and line pressure control electronically. The harder you can clamp the clutches/bands (i.e avoid slip) the less heat you transfer to your fluid, however, increased line pressure generates heat. So we find our selves in the usual automotive paradox, "no such thing as a free lunch".

Personally I've seen many stock auto's take about 500 fw lbs/ft without to much complaint, just get a decent cooler matrix on there. If you get fed up with shift lag, shim B3 and C2 accumulators (that's if you can on the MkIV supra version).

I'm sure Raybestos Blue clutch kits are available for the A340E should you need some increased longevity at that performance level.

This is something I plan to look at more closely in the near future to paddle shift the A340E going in my MR2.

Lyndon.

Every box is different mate, you cant put a figure in your head and say i will be safe at that level.

Mine runs a T61 at 1.4 bar making 465 fwhp and 490lb torque, over this and the box was starting to slip when mapping. This is with a mocul cooler to. The previous owner used to run the car at 1.6 bar for years, eventually that box broke, hence it has this one fitted now. But as far as i know its the torque being around 500 that is getting around its limitations

Im running a 71 in now and 'seems' ok at 1.2 with ability to do 1.7 (occasionally). I agree with what your saying Stonkin.