Board logo

Autobox discussion
alistairolsen - 10/7/08 at 11:18 AM

This stemmed from the end of the V8 thread in this forum but I felt it warranted its own thread.

I HATE conventional autoboxes, I want to choose when i change gear, I want it done smoothly and quickly. most manufacturers in the mainstream market havent got round to stuff like matching the throttle thru the change properly so they always jerk.

NOW, if one could get an autobox, and seperate its control from the engine ecu, would it be possible to get a simple up/down sequential mode, park and reverse?

How do weights of boxes compare?

Anyone tried it?

discuss


Guinness - 10/7/08 at 11:21 AM

Personally I wouldn't bother.

I used to have a BMW540i V8 with a Tiptronic gear box. You could run it in fully auto, sport or take manual control of the 5 ratios.

Auto was OK, Sport was fun, Tiptronic was just too slow / jerky.

Put me off auto / semi auto cars for ever I'm afraid.

Mike


Mr Whippy - 10/7/08 at 11:28 AM

I have had tons of auto's over the years, have two a the moment, some have been superb at changing smoothly others a bit clunky. I don't think I will ever buy a manual car again, I don't see the point and TBH loath sitting in traffic with a manual. If you want to go to a gear just use the shifter.

Although I have fallen out with them due to crummy engines, the Vauxhall Cavalier and Vectra both have very good auto box’s and the sports modes worked very well giving good engine braking and freewheel when disengaged. My old 406 auto though drove me nuts as it never got the gears right especially going round corners.

So don’t let one bad one put you off altogether.


[Edited on 10/7/08 by Mr Whippy]


Hammerhead - 10/7/08 at 11:29 AM

does the vw dsg gearbox fulfil this role? not for a v8 application but maybe a 4 cylinder midi.


David Jenkins - 10/7/08 at 11:31 AM

I've had a couple of auto cars - both Toyota - and I'm with Mr Whippy. For the sort of driving I do in the tin-top (either town traffic or long-distance slog) an auto is perfect.

But I'll keep the manual box in my Locost, thank you...


JimGTI - 10/7/08 at 11:31 AM

While i was at the Nurburgring earlier this year i was able to go round in the latest Golf GTi (230hp edition) with the DSG box. I have always been very dubious of autos but I was amazed at how good it was.

You were always in the right gear constant acceleration (when required) and when you do put it in tiptronic mode it was super fast to change gear either way.

In full auto it was like have a CVT box.. would highly recommend one on any VAG... on a kit car... half the fun is changing gear (imo)


speedyxjs - 10/7/08 at 12:14 PM

Its hard to wheelspin in an auto


Mr Whippy - 10/7/08 at 12:38 PM

quote:
Originally posted by speedyxjs
Its hard to wheelspin in an auto



erm

drive them with one foot on each pedal, at the lights just before they change, press both down hard and let go of the brake as the lights change...........G FORCE!! eat dust stick shifts


brynhamlet - 10/7/08 at 01:17 PM

I had an AUDI 2.5ltr with auto box as a courtesy car when my car was in for servicing. 7 speeds smooth as anything in auto. in sport auto, would red line before changing gears, if you are working the car hard anf manual was a sequential box sans clutch. And you got engine braking in manual.


symbiont - 10/7/08 at 01:50 PM

Hi, Have been considering using an autobox for sometime BUT there seems to be a lack of information on them , has anyone a list of whats available and what it can be connected to bellhousings etc or is there someone here who is an autobox specialist who can post this information. After all the pro drag racers all seem to use auto boxes


mr henderson - 10/7/08 at 03:00 PM

I really like automatics and they are very much the coming thing. They are getting better and better and come as standard on most cars with bigger engines.

Years ago I ran a TR7V8 3.9 and at one stage I put an automatic in it. It was delightful, the acceleration in 2nd was extreme. The responsiveness was entirely adequate and there were never any worries concerning gearchanges at awkward times.

I only changed it back to manual because I couldn't get a 4speed auto (top in the 3spd was direct).

Hi performance autos are commonplace in the states, and are much used in competition.

Unfortunately I haven't yet come up with a solution to the electronic control of autos being managed by the engine ecu. Ok I guess if you are going to use the original ecu but even then there can be problems depending on how complex the original set-up was (usually very complex the more expensive (bigger engine) donors)

Most of the electronic autos still have quite a bit of internal hydraulics controlling them, with, as far as I can tell, the shift signal coming from the ecu via relays. If those signals could be sent from a manual control instead then that would be a good solution from my point of view.

John


alistairolsen - 10/7/08 at 03:50 PM

its mainly for stuff like the lexus v8 where you cant easily get a manual box, but you can get a very good auto for bleep all in the donor, or equally the bmw ones.

/most of the high end manufacturers were ahead of their time a little so the *should* be pretty good?


Ivan - 10/7/08 at 05:07 PM

I run an auto box in my Cobra with Chevy 350 motor.

It works for me - much easier to control wheelspin and fantastic for cruising - wouldn't dream of changing it but also wouldn't contemplate one for a Locost - the motors are very different - high revving low torgue motors are better served by manual gearboxes to my mind or very sophisticated auto boxes which are basically clutch pedal-less manual boxes.

Once again its a matter of horses for courses.


mr henderson - 10/7/08 at 06:04 PM

But a 4ltr V8 with a good autobox in a suitably modified Locost, that would be sublime perfection

John


MikeRJ - 10/7/08 at 06:35 PM

quote:
Originally posted by Mr Whippy
drive them with one foot on each pedal, at the lights just before they change, press both down hard and let go of the brake as the lights change...........G FORCE!! eat dust stick shifts


Stick shifts? You living in the good old US of A these days?


Volvorsport - 10/7/08 at 07:31 PM

you guys dont search hard enough !

the AW gearboxes can be controlled seperately with a controller, but this would assume it doesnt need to talk to the engine ecu .

you can even use flappy paddles .

the shifts are pretty much like the auto gearbox before hand .

i know a couple of guys in the states running them in there VOLVO !!

its quite tempting to me since it means i could fit a T5 engine in tomorrow , also they have much better ratios for 1st gear .


alistairolsen - 10/7/08 at 08:15 PM

AW boxes?

are the vlvo autoboxes as big as the M90 casing?


mr henderson - 10/7/08 at 08:45 PM

quote:
Originally posted by Volvorsport
you guys dont search hard enough !

the AW gearboxes can be controlled seperately with a controller, but this would assume it doesnt need to talk to the engine ecu .
.


What's an AW gearbox, and what good is using a 'controller' if it does need to talk to the ecu?

But, if you do know of a source of external control units for auto boxes then I would like to hear about it

John


Volvorsport - 10/7/08 at 11:02 PM

AW70/71/72 or AW 34 as used in the supra .

no , there no bigger than a type 9 , its the sump that really wide .


the controller are made for the off road guys .


mr henderson - 11/7/08 at 06:57 AM

quote:
Originally posted by Volvorsport

the controller are made for the off road guys .


Any more info than that? I tried a couple of searches but didn't come up with any actual controllers.

John