Hello everybody, I've been on the forum for a little bit now lurking and trying to collect info about my car, but I can't seem to find certain information.

It's currently being stored in a heated garage, and I'd like to get started with getting it summer ready soon.

It's an '81 L28ET with the jatco automatic transmission. I will be keeping the auto for now, as manual trans are hard to come by, and I don't exactly have the time for an tranny swap.

I've driven the car all last summer and I just want a little more out of it. I'm not looking to go crazy with it however, I'd prefer to have a nice cruiser than a track *****. Anything I do to it will have low-end performance in mind. I would like to take it up to the local 1/4 mile once or twice a summer, but if that's out of the realm of possibility I won't lose too much sleep over it.
It's already got the urethane bushing package and feels very tight. I don't know how much body roll a regular Z has in the corners or quick lane changes, but mine seems to have very little.

I do want to swap to an LSD for better low end acceleration, and this thread has responses saying 3.7, 3.9 and 4.11. I don't care very much about mileage (my winter beater is a 5.0 AWD Mountaineer, ouch.) but being the auto trans and an 1981 without a torque converter, I don't want to rev too high on the highway. It's my daily driver in the summer. So which diff would be best suited for the auto? I can't find too much info on if I need to swap driveshafts. I think I also need some sort of small cog that goes to the speedometer cable to keep the speedo accurate?

I'm also wondering how much power the auto transmission can take? I'd like to turn the boost up but the last thing I need to do is rebuild or replace/swap a transmission. I believe that 10psi is the max without new injectors and an intercooler so I was thinking 8.5-9 PSI. I will install an intercooler later on (in the summer I hope) but not immediately.

I plan on getting the Borla XR-1 muffler. To me it has one of the nicest sounding exhaust notes of a 280zx I've ever heard. If anyone can recommend something better though I'm all ears! I'd much prefer the twin tip, to keep it as stock looking as possible.

A little info on the car; it's the GL coupe model, black on black with 150,000km / 93,000mi on it. Bought new in Quebec, it's been a garage queen all it's life. I don't know if it ever saw snow, but myself and the previous owner haven't put it through any. These cars are very hard to come by in atlantic canada, but not too sought after either.. I'm also told that the snowflake-style rims are hard to come by, is that true?

Any help would be much appreciated guys!!

Oh, and some pictures for your trouble:

 

Nice to see such a nice Z in Nova Scotia. Yours is almost exactly the same as mine. 81 turbo...

 

Thanks. Where are you located?

I also figured out I will be getting a 3.9 rear end gear, and I will probably end up putting an intercooler on before summer as well. Basically all I need to do is add the intercooler, run the piping, and get a new wastegate actuator to run higher boost? I could be wrong on that though, and I do not know if I need to do anything to the ecu however.

 

That is a nice zx. I'm jealous haha
I hope someone can help you with your noob questions. :-)