Well, there have been alot of documented steps on doing the R154 swap for the IS300. I have searched and searched many days, weeks, and months on this forum and came out with alot of useful information on the swap. However, there were a few unanswered questions that were left for me to ponder and find out on my own. The original R154 swap thread with the OG lack alot of pictures; I don't like to read, I love to look tho.
I am not going to do a step by step tutorial, I have just starting this thread to clarify a few questions and to show a few things I have done differently.
Here are the specific details of the parts I have, as many things may vary for some guys.
-Rebuilt R154 Transmission (86.5-92 Toyota Supra Turbo 7M-GTE). The transmission have the Marlin Crawler upgraded parts.
- W55 Ralco Short Shifter
- Machined Aluminum Crossmember
- MKIII R154 Rubber Mount
- ACT Clutch Kit
- 1J Flywheel
- MKIII Slave
- Shifter Housing Extension
-1JZ Bellhousing
- ARP Flywheel bolt
- Driveshaft Shop Steel driveshaft
W55 Short Shifter
There have been quite a few talk over on SF about whether or not the W55 shifter will work on the R154. The answer is No and Yes. The OEM W55 shifter will not work, however the Ralco (B&M) replica does work with modifications. It took me 3 days to figure out how to get this thing to work. And it also took me 2 more days to figure out why my initial adaptor didn't allow me to get into 5th gear. I finally got everything figured out and the adapter machined to work. I am truly amazed by the shortness of shifts, compared to the OEM MKIII shifter. With the MKIII shifter, inorder to get it into reverse the hand brake has be up and all the other gears the shifter would hit something.
The shifting is VERY crisp, unlike the sloppy MKIII OEM unit. This is because you are getting rid of the spring/pivot ball.
I will not disclose what I did in detail as a repect to my machinist and myself. I truly put alot of R&D into this part of the swap. However, I will say that you will need an adapter piece which I spent numerous hours on CAD to draw out.
Shifter Housing Extension
I did not do the typical dogtail trick to the shifter assembly, instead I extended the shifter housing. Without this you will not be able to get the W55 shifter to work at all. So this is a MUST if you're planning to use a W55 SS. The extension lands the shifter hole almost centered.
Crossmember/Mount
There have been members on here who have said all they need was a few spacers to use the OEM mounts. I couldn't really see how that was possibly because with mine, I needed a 2" spacer. Instead of reusing and redrilling the OEM IS300 crossmember, I had aluminum stocks machined out. With the MKIII rubber mount, all I had to do was mark and drill one hole because those mounts only have one 1/2" bolt holding them down.
I really don't like how low the mount seats, with the head of the bolt it is 1/4 lower than the frame rail. I might come up with a one piece solid mount with rubber inserts.
Electrical
I haven't gotten this far yet but once I do, I will update.