Posted this in the gearbox section and no one replied so thought i would try in here. I've been thinking for a while without doing any real research on the topic, but is there any reason why no one builds 5 or 6 speed auto's like the ones found in the VE's. I noticed the v8 models still retain a 4 speed (i think) so im assuming the 5 and 6 speeds just wont cut the mustard when it comes to big power but surely there is an auto out there that will be able to take some decent power with atleast 5 gears. If there is, surely it would be the best of all worlds. Driveability with minimised lag and the ability to keep the car in its powerband for longer. That being said im sure there's a reason why no one uses them so shed some light transmission guru's.

then again the bmw box which is in the bf upwards in ford zf 6 speed auto are extremly stong...hold upto 400kw

biggest problem is alot of them are just made out of s#it and it cost too much to re-make parts for them to handle the power watch http://www.youtube.com/watch?v=7pkT9FdKpvc

Tony from Yarra valley autos has built the ford 6 speed designed his own valve body give him a call 03 9739 5444 it was pretty expensive and could handle some big power from wat he was saying

size > a 6 speed is much larger than a 4 speed cost > due to the "newness" and part availability, building a strong 6 speed will be expensive also difficult to find second hand. control > alot of our gearboxes are mechanically driven. linkages, small auto ecu. larger newer ones, are fully electronically controlled, hence shift up and down buttons and the like. so more cost there, and matching up the auto to the vl also a v8 has alto of torque down low and power right along the rev range, a mates 6 speed honda muzzbox didn't move until you had it close to the redline, the gears were soo close, they dropped 2k rpm or so from 8 when he shifted i might be talking ****, i dunno btw, bmw, amg, lambo, craparrari all have 6+ speed gearboxes in "auto" style boxes... well lambo runs a transaxle, so does craparrari, so that counts them out...

Quote: Originally Posted by FORZA [View Post] I noticed the v8 models still retain a 4 speed (i think) so im assuming the 5 and 6 speeds just wont cut the mustard when it comes to big power. The current commodores use a 6 speed auto behind both the 6L V8 and HSV's 6.2L V8. Corsa

Goes to show my interest in commodores built after '88 . The current 6 speeds must be a bit beefier. So the main reason is cost? Be interesting to know the cost to build the 6 speed from yarra valley. Just goes to show that it can be done, i think its only a matter of time before someone makes a full manual valve body for a GM 6 speed (if they havent already). Does anyone have any more info on the 6 speed yarra valley built? Dont really wanna call and waste their time. Some original photos have not been recovered yet.