I know the bolt pattern to the engine is the same, but what about:

1. The rear cross support.
2. Shifter access.

To get even more trivial, could I put a automatic from a 2nd Gen into a '84-85 1st Gen in a straight bolt in exercise. Not worrying about the elctricals for this thread in this case.

 

Also, what about the drive shaft length and bolt pattern to the rear differential?

Is there a rear tail swap that will make things line up if there is a difference?

 

I curuntly doing the same the g'box will bolt right on. the driveshaft u will need to shorten it, the end that goes to the gearbox is bigger than the 1st gen. and the other end is different again, so what i have dun is got myseft a Series 4 driveshaft and cut off the top end off and welded it on the 1st gen driveshaft. the other bits, i haven't looked yet.

 

rear support bracket is out a bit and the shifter is out about a 1/2 a inch

 

The tailshaft housing can be removed from the 2nd gen trans and replaced with the first gen tailshaft housing. This will put the shifter were it should be and mount to the crossmember in the stock location. Be sure to swap out the shift rod ends as well as the housing.

I did a similar swap using the 2nd gen trans and a B2000 pickup truck tailshaft housing (same trans as the RX-7) to get my shifter further forward.

 

To make sure nothing was lost in the translation, do I read that you were able to use the stock 1st Gen driveshaft if the trail shaft housing is swaped onto the 2nd Gen tranny?

 

Yes.
After re-reading your post, you should be able to replace the tailshaft housing and shift rod ends on the 2nd gen trans with that of the 1st gen trans. This will get the shifter and trans mount in the correct location. You can use your 1st gen driveshaft since the motor has not moved from the stock location.

 

Why are you swapping the tranny's? Are the 2nd gens better? I have access to a 2nd gen tranny(not sure what year), so I might be interested, if there is any sensible reason in swapping other than that's the only tranny I could find. Is there any specific year tranny that will work?

 

So your tranny mount was out by half an inch? Like the difference between a 13b and 12a ?
Perhaps motor mounts are subtly different?

Anybody know about 2nd gen auto to first gen auto swap? I've got the 2nd gen four-speed and an eye on a first gen car. I don't mind a custom shaft or such but I don't want a poorly mounted tranny jumping into my lap when I've got foot into it in a corner.

 

T2 gearboxes are alot better than the older gearboxs.

Myself, A777 and 10sec_RX7 are all doing flat 11s or better on T2 boxes.

 

The Turbo II gearbox has a bigger input shaft. It will not fit on the stock 225MM clutch. I did the research for 12A Bridgeport into a second gen (I had them available). To use the turbo II gear box you will need a clutch with the same OD as 83+ 12A but with Turbo II splines. Like this one from RB
http://www.racingbeat.com/resultset....rtNumber=12525

You could just use a non-turbo second gen box without the need of the clutch. I am unsure if you would benefit in the non-turbo swap.

-billy

 

very interesting mister bond

 

I searched and I searched and I found a thread that helps. Way to go Search funtion, hip hip hooray.