4 speed auto strength?

[ten[A]cio[U]s]

Some of you may know, some of you wont but i am currently in the early (very early) stage of turbo-ing the fairmont.

Ok i have sorted all the prices out with the engine side of things but i am curious as to how far i will need to go at strengthening the 4spd auto.

I have been told that the gearbox in the AU's is rather strong and can handle a lot of power, but im not too sure how much. We have worked out that with the setup we are aiming for it will get around 350rwkw on 12ish psi. I know that with this sort of power i will last maybe one launch and then have to pick up peices of the box for the past quatre mile..

I have seen a few AU's with a lot of power with the stock box and have no problems, just not sure how long they will last..

Just curious as to how nuts i will have to go from other people experiences to handle this much power?

[b2tf]

Beef it up matt. no point having power if you cant get it to the wheels.

[poolkeeper]

Casper has a bullet proof auto...

[just me]

i'm a tranmission mechanic in bendigo and we have built some of the btr transmissions to hold a fair bit of power one is in a hyundai drag car that puts out 680 hp at the wheels and some other xr6 turbos that are fairly powerfull to the best thing to do to them is kevlar bands and upgraded frictions and steels and also by running a variable pressure solenoid out of a 4l60e transmission (commodore) you can boost up the line pressure and make the trans feel alot firmer and more positive and also the torque converter would have to be upgraded but you would have to get a power figure and talk to a trasmission specialist and they could get a custom converter made for your needs so there is no reason why you cant just use the standard trans beefed up a bit hope that give you something to think about
cheers

[ten[A]cio[U]s]

Cool cool. I knew it would have to be beefed up, just not sure how much.

I have a few other questions too if you could help too mate.

How much difference is there in the standard BA and xr6t gearboxs?
How much difference is there from the BA and AU gearbox?
What sort of peak power are we looking at out of the stock AU gearbox?

Cheers, matt.

[rag top]

What is the internal differences between the V8 and the I6 box??

[just me]

standard ba and ba xr6t gearboxes are mostly the same only difference is they use a slightly larger planetary set like in the ef/l and au v8 boxes standard ba and au box selector shaft and the case are different because the ba uses a cable selector so the selector shaft does'nt stick out both sides, bellhousing is different it has mounts for selector adjustment, extension housing is different no hole for speedo transducer as you may no ba's read speed of the abs and also inhibitor switch is different. peek power handling depends on what condition your box is in now how many ks that box has done and if you have had it serviced regularly play a major role in how good it will be but i have seen stock ones handle around 200 kw at the wheels on a na six or turbo six.
difference between v8 au and 6 cyl boxes are output shaft is longer so therefore extension housing is longer, input shaft is different, bellhousing is different and planetary set is different.
cheers

[justa6]

man if you want 350rwkw going through it get it as strong as they can make it, with big oil cooler. maybe give paul from keas a ring might be cheaper do get a 3 speed straight up.

[StealthAu]

crazy-au Just wondering, what ecu you plan to run this?

[ten[A]cio[U]s]

Wolf 3d v4 or Autronic.

Still trying to decide which would be the best for what i intend to use it for.

Going to be a lot of maney poored into it, so i want to make sure i spend it wisely..

[Mechan1k]

Originally Posted by just me

i'm a tranmission mechanic in bendigo and we have built some of the btr transmissions to hold a fair bit of power one is in a hyundai drag car that puts out 680 hp at the wheels and some other xr6 turbos that are fairly powerfull to the best thing to do to them is kevlar bands and upgraded frictions and steels and also by running a variable pressure solenoid out of a 4l60e transmission (commodore) you can boost up the line pressure and make the trans feel alot firmer and more positive

cheers

This is pretty much what I got in my replacement BTR for the ute ... was built for another AU to handle about 550hp ... the person didn't have the funds for it ... and I bought it.

Handles heavy load carrying soooo much better than the old one ... and handles heavy city traffic in the heat so much better.

Also helps to have a decent transmission cooler too.

[just me]

a trans cooler would definatly be needed aswell especially if you are going to use a high stall wich i would say you would be

[Mechan1k]

I use the standard stall converter ... as I float horses ... they'd be straight out the back if i was running a high stall ... LOL.

Also heavy load driving doing courier work too ... a high stall would be annoying.

Will be going for shorter diff gears in the near future though. This will help me more for my application I think.

[ten[A]cio[U]s]

Yeah will have a high stall and trans cooler. I will be going the 10"x11" PWR model. I have heared good things from some local people plus a few people on here.

Well 550hp will definatly be what im after. Running the setup i will be will have close to 400kw at the engine so thats right on the money really.

How much would it cost to build a box similar to that strength Mechan1k?

[b2tf]

Originally Posted by crazy-au

Running the setup i will be will have close to 400kw

Is that all :

[ten[A]cio[U]s]

Still a long long way to go Austin, by then the ute will be up there. :eclipsee_

Be fun to see the two when complete (if ever) :MrT_anim: