Custom short shifter for the 30A (FS5R30A)

There is currently no dedicated short shifter kit available for the Z31 30A (FS5R30A) transmission. The stock shifter has very long travel and is not very precise so I wanted to see what I can do about it. I'll share the info I gathered for myself and my experiences in adapting a different shifter. This is more of a collection of info than a guide, but it should help if you want to do something similar.

The Made in China copies of the C's shifter for the S chassis are available and can be adapted (sometimes also listed for R series, but really based on the shifter for S). Z_Karma has written a good installation guide for it
https://z31performance.com/forum/z31…r-in-a-fs5r30a

I had bought one a long time ago already, but I was skeptical about it. I'll first share what I did and go over the reasoning later.

I found a new OEM stock shifter for the ECR33 for fairly cheap and I ordered one (32839-21U10). The shape is slightly different, overall length is very similar, but most importantly, the fulcrum point of the lever is slightly higher up. The rubber bonding the two pieces together is a lot softer than on the Z31 lever.





Next, I had a couple of aluminium rings machined to replace the spacer ring from the kit. I wasn't sure which fits best, so I had one made 8 mm tall and the other 10 mm. I ended up using the 10 mm spacer. It doesn't flatten out the wave washer entirely and leaves a tighter feel. Anything over that and you'll end up compressing the plastic socket. Spacer ring outer diameter 49.5 mm, inner roughly 39-39.5 mm. You can use the plastic socket for reference.



Mocking it up. I also replaced what I could with new parts: the shifter socket, the wave washer (they do wear), and the lower rubber boot (supplied with the shifter). The ECR33 uses the same type of shifter bushing (unlike other R chassis 30As) as the Z31, also already on the shifter.




I also modified the mounting plate from the kit so that I could install the small lower boot. It looks like a hack job, but it does what it was intended to do and looks just fine with the boot on. I'll probably have a custom one machined eventually.





I also made a little gasket from gasket paper. Not my idea, copied it from the Nismo kit.



Like I said, the rubber in the ECR33 lever was really soft so I cut up a poly bushing to make an insert and stiffen it up. I epoxy glued it in there, I guess it works as intended.



Installing it.



I removed the large worm gear clip and replaced it with a cable tie, but no photos of that.



The top cover bulges up pretty strongly. I was thinking about getting a Z34 boot to replace it, but haven't got to that yet.



Side by side comparison of shifters in action



The shifter feels a lot nicer and I'm happy with it. It's not super short, but travel should be about 15-20% shorter which is pretty much what I was hoping to get. It retains the bushing inside the lever so no chance of rattling like some people have reported with the fully solid shifter.

- - -

Coming back to the Made in China copies of the C's shifter. I have seen people post about problems with that shifter on different cars. I think there is good reason for that because it doesn't really fit the Z31 30A that well, even with the already listed modifications. Most importantly, the spacer ring in these kits does not match the difference in the lengths of the levers. The tip of the shifter lever ends up too deep in the shifter arm. This is probably also the case with most of the R chassis 30As if this short shifter is used. The mounting plate is copied from C's S chassis shifter, which is different from the one used on R series 30As.

Basically, the longer the distance from the fulcrum ball to the tip of the lever, the higher the plastic socket has to go. This is achieved with the spacer ring. However, if you raise it too much, the pins on the sides of the socket are raised out of the grooves. Also, with the socket high up, tightening the square plate on the top will put stress on the plastic parts and flatten the wave washer.

The stock Z31 30A shifter is quite similar to shifters on most R chassis 30As. There may be minor differences in lengths and the bend, but the main differences are the bushing at the tip and the rubber bonding the two parts of the lever. The rubber in the Z31 lever is a lot stiffer, meaning the Nismo solid shifters will likely not make much of a difference.

Some specs and info. Length is measured approximately between the centers of the balls.



The original shifter - 40
ECR33 - 48
Made in China kit - 61,5

From the fulcrum ball of the lever to the tip of the lever the short shifter lever is approximately 22 mm longer than the stock Z31 lever. The spacer in the kit is 14 mm tall. This means the tip of the lever would stand 8 mm lower than it should.

In simple terms, the height of the spacer ring should at least roughly match the difference in these lengths between the shifter levers. A couple of mm difference should be no problem.