As many of you know, I inherited my Dad's 1984 300ZX turbo when he passed last fall. Original owner, GLL model, fully loaded, automatic transmission, 96k miles. The car had been sitting for 3 years when I got to it, started up and ran, but needed some attention.

Got it to my Z wrench guy and told him to go through the car completely, whatever it needed, do it. New stereo and speakers, fluid channges front to back, top to bottom, new tires, etc, etc. On his test drive he noticed that the transmission had a "shudder" in first gear, not good. Doing some research, I quickly discoverd that the automatic transmissions in the Z31 were pretty much crap. All signs point to the tranny failing in the near future. Other than that, the car is SWEET.

After getting a quote from a transmission shop of $1200 for a rebuild ( ), never being a fan of automatics in sportscars, AND noting the perfect Z31 5 speed transmssion that is sitting in my garage, I decided to look into a swap.

Xenon's Z31 site gave a blow by blow description of what is needed and how to do it ( http://xenonz31.com/autotomanualswap.html - outstanding!) so now I am tracking down some of the parts I do not have.

NEEDED:
Z31 clutch pedal assembly
Z31 brake pedal assembly
Z31 TURBO ECU for MANUAL transmission
Z31 84-86 driveshaft

I want to get going ASAP to get this car on the road and happy again. If any of you have the parts above to spare, OR can offer advice if you have done this swap, I am most appreciative.

Stay tuned......

_________________
John Taddonio
1970 240Z
1977 530Z
1984 300ZXT
zcarnut@hotmail.com
FB: Zccr zcarclubofrochester

I can offer a bit of advice in this area. First is that you can use the existing ECU in your car, auto's will work fine a manual car but not the other way around. Secondly, you will need to jump the neutral safety switch in the auto's harness. This is pretty straightforward on 85-89's but IIRC the wiring is a bit different on 84's. When doing the hydraulic plumbing you can use the front brake hose from just about any S30 (either right or left) to connect the clutch slave to the hardline. Other than that it is a pretty simple swap, just nuts and bolts. One thing you failed to specify: which type of manual tranny do you have? The driveshaft is different between the 84-87 n/a (FS5W71C) and the 84-87 turbo (T5).

Least fun part ahead of you: pedal removal/installation Now would be a good time to hire a 5 year old to crawl under there an contort themselves and save yourself some chiropractic fees.

Good luck and keep us posted!!!

Edit: 84 specific wiring included in Xenon's writeup



Don't forget to get yer hands on the appropriate tool to remove the auto-specific pilot bushing on the back of the crank.

I agree with Greg regarding the ability to run an automatic ECU with a manual transmission. I did that for over a year after I swapped my 280zxt over to a 5 speed. I also agree that sports cars should be manual! But here's a few things I did notice after my swap that you may experience.

Disclaimer: I realize that the 280zx and 300zx are different models, but they probably have more in common then not. As a matter of fact, I've just about completed swapping in a 300zxt ECU / MAF in my 280zxt.

A year or so after my auto to manual swap, I was curious to know if a manual ECU would perform differently then my stock auto ECU. After swapping in a manual ECU, I did notice a difference in the way the RPM's are handled between shifts. With the manual ECU, the RPM's fell off slowly when I let up on the throttle. With the auto ECU, the RPM's fell off quicker, so you tended to feather the gas pedal between shifts a bit in order to get smoother shifts. There are also internet rumors that the auto ECU's do not have a rev limiter, though I did not test this .

I also failed my next state emissions test, which I never had had issues with before. I pulled out the FSM and started getting educated on the EGR system when I noticed that it looked like the ECU may include the park / neutral switch when determining whether to open the EGR valve. Before I was able to solve the emissions issue, I installed a 3" custom exhaust with a new hi-flow cat and also permanently disconnected the EGR. I was able to pass the test and my Z no longer requires testing since it is over 25 years old.

It may also be a coincidence, but my cruise control stopped working after the swap, not that I ever used it. It would make sense that the ECU would not engage the cruise or open the EGR valve if it is receiving a signal that the car is in park.

Now that I'm knee deep in rewiring for my ECU swap, I plan to once again study the park / neutral switch in an attempt to get the cruise control to work.

_________________
Phil
1981 280zxt - Now in the care my son!
2014 370Z Sports Touring Roadster

I am installing a 1987 FS5W71C 5 speed into the car. I understand the difference in the drivrshafts and am having a shop build me one from the 87 and 84. I'm told the flanges are different. Unless one of you out there have a 84-86 manual driveshaft you can express ship to me, hint, hint.

I've also learned that the auto ECU will work with the manual just fine.

Got a fine young strapping son in law to do the pedal swap for me. We might just pull the dash to make it easy.

I'm a little concerned about the neutral switch, but we'll figure it out.

Next weekend, surgery begins!

_________________
John Taddonio
1970 240Z
1977 530Z
1984 300ZXT
zcarnut@hotmail.com
FB: Zccr zcarclubofrochester

The surgery begins this weekend! Cross your fingers......

_________________
John Taddonio
1970 240Z
1977 530Z
1984 300ZXT
zcarnut@hotmail.com
FB: Zccr zcarclubofrochester

Good luck John, I'm sure everything will be fine. You may want to consider removing the driver's seat to gain easier access top the pedal area.

The park / neutral switch mod is a no brainer, just connect the two wires from the harness together!! Cake walk! I only listed my "potentially" unrelated issues in case you experience any yourelf.

_________________
Phil
1981 280zxt - Now in the care my son!
2014 370Z Sports Touring Roadster

Success!

My 5 speed swap into my '84 300zx turbo automatic is done and working fine. What a difference! It is absolutely like a new car. Much more responsive with the turbo, a blast to drive.

The process was pretty straight forward, the only real nightmare was installing the brake and clutch pedal assemblies. It required removal of the dash (digital!) AND the steering column. With my enthusiastic 26 year old son in law doing the grunt work, it took about 8 hours for this part of the job.

Only one gremlin left to sort out, have to figure out which wire in the harness connects with the back up light switch.

STILL NEED the upper shift boot retaining ring, the one that secures the trim boot to the console. Anyone have one to spare?

Thanks for all the good advice, I love this club!

_________________
John Taddonio
1970 240Z
1977 530Z
1984 300ZXT
zcarnut@hotmail.com
FB: Zccr zcarclubofrochester