8/70 240z transmission question

[ZcarFanMan]

I came across a 240z dated 8/70 vin HLS30008992 with A/C. It looks like it was converted from A/T to 4sp. Would it be worth it to swap back to A/T? I'm not looking for performance gains or anything. I just want to get it back to an original state.

I've never driven an AT z before, are they gutless? Should I just keep the manual and move on?

Opinions please.

Thanks

[Arne]

8/70 would have been a very early automatic. What changes do you see that make you think it was converted?

[ZcarFanMan]

There's oil cooler lines coming from the bottom of the radiator that are capped off at some metal plate. I'm just going by description of what my friend gave me. The car is still in reno, on my next run reno in a few weeks i'll pick it up. Lucky for me i'm an auto transporter so it'll be a breeze. Hmm, I read that it was mid A/T production era. Maybe it's a true 4 speed.

Thanks!

[djwarner]

According to Carl Beck, the first AT was SN 08942, so it may very well have been in the first batch of AT's produced. Mine has a oil lines running from the AT to the oil cooler built into the radiator. The automatic transmissions were the same for all the S30s as well as several other cars from the era.

Finding the AT console and shift lever mechanism may be harder to find than the transmission itself.

As for performance, what are you driving intentions? Mine is a daily driver in a suburban environment. 4 speeds can get tiresome in an urban environment.

Edited May 24, 2014 by djwarner

[ZcarFanMan]

Looking at a pic he sent me and his description of the console I think it's just missing the outer shifter boot for the stick. Maybe?

Here's a pic, not too good but you can see what I mean.

My intentions are weekend driving, occasional trips to vegas with the wife (250 miles one way). Nothing that requires a led foot.

How's the get up and go factor with the AT compared to the manual? kick down for passing as opposed to down shifting etc..

thanks

Jim

[nix240z]

There are a few little things different on auto and manual cars that you can look at.

the console was cut for the auto shifter.

3 hole brake and fuel line insulators vs 4 hole for the clutch line.

no bracket on right side of the transmission tunnel for the clutch slave hose

no clutch stopper bracket or pad on the inside drivers side firewall.

fire wall insulator will not be notched out for clutch stopper bracket

plus other little things.

steve

[ZcarFanMan]

Thanks!

[jfa.series1]

Perhaps the radiator was swapped out at some point with an AT version - possibly from a salvage yard?

[djwarner]

A quick snap of my console showing the automatic shift lever assembly.

To be honest, for your driving intentions, converting back to an automatic would be low on my priority list. Yes, a three speed automatic without a lock-up style torque converter will not be as peppy as a 4 speed. It will kick down from a vacuum switch or from a kick down switch when the throttle is mashed to the floor. Differentials are also different ratio 3.54 for an AT, 3.9 for a MT.

[Arne]

You could look at the write up I did years ago on a similar vintage auto-to-4-speed swap. Imagine doing the opposite. The article also outlines some of the differences between the auto and manual body shells.

http://www.classiczcars.com/forums/tech-pubs-howto/21274-240z-260z-280z-auto-4-5-speed-swap.html

In the end, unless the car is a really nice time warp car that might benefit in value to being 100% original, I doubt that I'd go to the effort to swap back to the auto. The automatics don't totally ruin the car, the little six has enough torque to make it work. But the effort to go back might be considerable, and parts to do so could be hard to come by.

[ZcarFanMan]

Finally picked her up yesterday. Here's a few pics of the lines from the radiator that are plugged and the tranny.

[Arne]

As a guess, I'd say yes, it used to be an automatic. Post a picture of the left front fender well in the engine compartment, showing the ignition coil and the area below and in front of the coil. That should pin it down for certain.