when using a CA engine, we spoke to someone about wiring up the datto with a CA, and he recommended using a CA20 gearbox (i am going auto) as when wiring it up the CA20 box is easier to wire up and it also uses 1 less computer as its a hydraulic box, and it fits straight onto the ca18.

Also when using this box the gear changes are alot smoother.

the CA20 auto box is also smaller then the CA18 auto box, still needs the trans tunnel upgrade.

It comes out of a Series III Bluebird. we picked ours up for about $250 i tihnk from some jap wrecker in smithfield, nsw.

I am unsure if you are going auto or manual trans, also i dont know if the CA20 box was auto and manual, but this is the info i know about using an auto ca20 box with a ca18det.

i am sure someone will correct me if i have said anything wrong in regards to the gearboxes and such as i am not too knowledgable on these matters. I hope this helped.

Cheers

Kirstie