swapping a tb42 for a tb45 in GQ auto

[toy77]

G'day all,

I have looked round the bible and pretty much any thread on the TB motors over time.

i am considering fitting a TB45 to my TB42 powered GQ.

i think from what i have read - this should be a straight swap - ie they are the same block.

So engine mounts should line up, and my auto should bolt up (the motor is from a manual)

I believe the auto has its own computer, probly with a tps feed.
Any probs runin the 45 with a manual comp to my auto box?

Any advice or suggestions appreciated.

Cheers
Stew

[bogged]

Any probs runin the 45 with a manual comp to my auto box?

I would expect the manual and auto computers to be different kettles of fish.

[giantracing]

G'day all,

I have looked round the bible and pretty much any thread on the TB motors over time.

i am considering fitting a TB45 to my TB42 powered GQ.

i think from what i have read - this should be a straight swap - ie they are the same block.

So engine mounts should line up, and my auto should bolt up (the motor is from a manual)

I believe the auto has its own computer, probly with a tps feed.
Any probs runin the 45 with a manual comp to my auto box?

Any advice or suggestions appreciated.

Cheers
Stew

mate give me a call i will tell you what to do........... better yet i have a full conversion 0438279890

[MyGQ]

the ECU and TCU are separate. this means that a Auto TB45 has an ECU for engine and a TCU for trans since the Auto used on the TB45 is the same one that came out of the TB42 series, RE4R03A to be exact.

i think there are a few wires that need to go from the TCU to the ECU but they should be pretty simple.

If you were running a Carby TB42 you will need to change over TPS feeds as the Carby one got it from a switch on the side of the carby where the TB45 gets it from the same sensor that the ECU gets its TPS from.

[cooki_monsta]

you will also notice a problem with idle return, as an auto ecu will return to idle slower then what a manual one would, this could cause some headaches with an auto box

[toy77]

Thanks for the replys,

Mine is an efi TB42.

i originaly thought i could leave the trans comp, and just conect tps, tacho feed etc.

But i was talking to someone about it last night, and he was telling me that the gq has seperate computers for trans and engine, but the tb 45 doesn't.
and although the auto look the same on the outside, they are different in operation.
The auto needed a signal from the computer for the tps etc etc - i couldn't take it straight from the sensor itself. and the end result would be the gearbox remaining in top gear at all times.
The only easy way around it was to use he tb45 auto as well.

Also is the tb45 still prone to the head issues of the 42?

It was also suggested i could just fit my manifold, injectors sensors etc to the the tb45 and run off my computer....
mine does run mostly on gas - but i would assume it may be lean with this setup. maybe up the fuel pressure a bit?

Cheers
Stew

[MyGQ]

TB45 don't have any issues with heads compared to TB42

As for using your manifold on the TB45 that won't work, the Exhaust manifold are the same, but the Inlet are totally different. they don't line up with the bolts

[toy77]

ok...

So if the TB42 and 45 are virtually the same motor - but the 45 is a bigger bore, different inlet.

Would be very simmilar in operation.

What is i were to retain my factory computer, loom, and auto.

fit my injectors into the 45 manifold, my tps and air flow meter all onto the 45 and basically run it as a bored out tb42.

I have lpg as well as fuel - lpg is easy enough to re tune.
perhaps check the a/f on petrol on the dyno - may be close enough, perhaps a fuel pressure adjustment, or and interceptor - AFC or simmilar.

Any ideas?
Worth the effort?

how much better do the TB45 go than a 42?

Cheers
Stew