HZJ75 Troopy Automatic Conversion (2 Viewers)

[dadinabarrel]

Thanks Maat

 

[dadinabarrel]

Progress report:

Looks a bit dusty in there but you get the picture It'll get cleaned at some point

 

[maat]

looks factory mate, nice job

 

[dadinabarrel]

Gonna be sweet in a couple of weeks when the engine mods are complete and I'm back on the road

 

[watrob]

Dadinabarrel, I am building another 40 series coil sprung all round chassis (offset diffs), using a RJ70 chassis, with another fully rebuilt 12HT, this time I am contemplating a auto?

What would be in your opinion a light weight auto trans (with t-case) that would work, it will be a beach vehicle, fibreglass sports tub. The 12HT will be around 150hp max, 33" wheels. I know the 60 series had a auto attached to the 12Ht but its a big bulky hunk of metal, looking something a little newer & lighter, any thoughts?

 

[dadinabarrel]

Mmmm, well the way I see it, you either stay with Toyota gear or move totally to something else. The Toyota A440F that I have in my Troopy is a great bit of gear. I added a Nomad valve body and a HD lo stall torque convertor to get a great combination of strength, fast gear changes and good lockup.

It comes down to budget and what your goals are. No one would ever question that a powerful auto in sand is king

I'd go for the A440F, with the FRP body your power to weight ratio will be great so the weight won't matter. Just make sure you put a nice big, thick bash plate under there and happy days.

 

[watrob]

What revs are you making in "drive" at around 90kph?

The problem I have is all my cruising is between 80 to 90kph, the 12HT is a low revving engine? what's the gearing ratio in "D"? is it .717:1 and 3rd is 1:1

 

[dadinabarrel]

A bit hard to tell as I'm in Perth this week and the Troopy is in Brisbane, but sub 2000rpm I'd say. At around 80 the torque convertor does it's final lockup and revs drop right off.

 

[dadinabarrel]

My workshop manual is in Brisbane as well, but I know that the gear ratios for the A440F are in the spec section at the front end.

 

[dadinabarrel]

Here ya go...

1st 2.950:1
2nd 1.530:1
3rd 1:1
4th 0.717:1
Rev 2.678:1

The diff ratio will complete the picture

You're in Brisbane, I'd love to come and check out your build some time

 

[watrob]

Thanks, just have to decide if I go 5 speed manual or 4 speed auto for the next build?

 

[dadinabarrel]

Power + auto = best

low power + auto = sucks

 

[watrob]

Ok what needs to be done if I buy a reco a440f or should I get a a440L, any addons or changes?

 

[dadinabarrel]

I don't know if you'll find an A440L, if you use the A440F you don't need electronics to change gears. I haven't fitted one to yours, you're welcome to come have a look at mine if you want to measure it up.

I bought my trans for $200, it was perfect inside, spotless, runs like a dream

 

[watrob]

What's operating your kick down?

Also forgot to ask, what diff ratios are running? the diff in this new chassis I am building are 4.55:1?

 

[dadinabarrel]

Kick down cable attached to the throttle lever on the IP

I think it's 4.33:1 for a stock 98 troopy, if that was the case in a like for like scenario, mine would be better down low and the 4.55:1 would have better legs/lower revs at cruise

 

[ozwallaby]

Kick down cable attached to the throttle lever on the IP

I think it's 4.33:1 for a stock 98 troopy, if that was the case in a like for like scenario, mine would be better down low and the 4.55:1 would have better legs/lower revs at cruise

4.55 would be better down low and 4.33 better up high methinks...

 

[dadinabarrel]

Yeah, I had it backwards, thanks

 

[ForealBoreal]

I thought stock 75s had 4:10s

 

[dadinabarrel]

Update, yerp, 4.10:1