TH 700 Commodore 4sp auto in a beddy

[willo]

Hi all,
in all these discussions about motors and diff ratios etc, has anyone put a 4speed auto out of a VN or VP commodore into their Beddy?  I'm wondering if it is a good thing or a bad thing to try.  My camper is a trimatic and I like the auto thing in it.  A 4 speed would give me an electric overdrive that i could control with a switch on the dash (maybe). 

Thanks

Neil

[Bas / NZ]

I run it in mine with a 4.1 diff, sweet as.

Overdive is not electric

http://www.buga.com.au/index.php?option=com_gallery2&Itemid=8&g2_itemId=31598

[willo]

Thanks mate.  I see that you also have a v6 in it as well.  How's that go?

I am thinking of putting the TH700 behind a blue 3.3.  Transport in NSW is making it harder and harder to do engine transplants.  My diff is 5.22 and an o/drive would help heaps.  It is 3 ton so the 5.22 diff isn't much of a problem.  It'd be nice to drop the revs in top gear to cruise better at 90kph. 

I am not sure if it is possible but I was reading somewhere that the lock up torque convertor is activated by a switch on the side of the box and that this can be overridden/activated by a toggle switch instead of the gearbox switch.  If so, and it is strong enough then i'm interested.


Cheers

Neil

[restoreid]

Hey Willo page 23 of my Camper Update posts there's a photo of my binlaw's 202 with TH 700 you will need an adaptor plate to bolt them togeather You cant use the lockup converter unless you use the computer but they usually leave it unlocked It is not a cheap conversion a diff change would be a far cheaper way to go

[restoreid]

By the way an Overdrive will only take about 800 to 1000 reves off at 100 ks

[bed767]

I have a308 turbo pattern, th7oo box with lock up that works to holden standard. i.e. locks up when conditions are right(steady speed, even load etc) but unlocks on hills, under load. all vn-vp boxes can be run this way with a simple conversion,no computer used.

[willo]

By the way an Overdrive will only take about 800 to 1000 reves off at 100 ks

The final ratio of the TH700 is .7 instead of the 1:1 currently in the trimatic.  About 30%. So if I am doing 3300 in top gear because of the diff ratio then this would be about 2300 or so at the same speed so that would probably be OK. 
Problem with changing the diff is that I would be underpowered at initial take off with only the 202.  The old girl is 3 ton plus all my junk in it.    I'm also nervous about getting the diff ratio just right because I only get one shot at getting it right.  Too expensive to change again.

It is gonna be costly either way I go but I am thinking if I keep the 202 (or blue 3.3) then I need to play with the gearbox first. 
I'd love to put a 5l v8 in it but I think with the current changes to engineering rules in NSW I probably would not get a new conversion passed.

Neil

[John Abbott]

Hi Neil....Geez 3 ton ,thats a fair load on the old red motor. With regards to the diff ratio, i have 3 commodores here 2 vps 1 vn and they are all running 3.08 diffs. Hooked up to the v6 they all can pull and tow a fair amount, and i used to have a LJ gtr torana that ran a 186 4 speed with a 3.08 diff in that. I am no expert when it comes to diff ratios but this 3.08 seemed to be the best for off the line and top end cruzing,i only wish my truck had the same as its a real slug off the mark.

[ben]

,i only wish my truck had the same as its a real slug off the mark. Grin

may have something to do with the 173 johno lol

[John Abbott]

oooooHHHHH FEEL THE POWER BENNY