JDM Engine and/or trans, will they fit?
 

Before I expend too much effort contacting various JDM engine importers, I guess I should check with you guys to see if the JDM engine and transmission will even fit in a USDM SVX. Since I've heard several times on here and seen some evidence that the JDM (or simply the ROTW-trans as the non-USDM trans has been called) transmission is much stronger and better than ours here in the US, I figure it might not be a bad swap for when this replacement breaks, as I know it eventually (hopefully many many miles down the road) will. Simply changing the trans would be easier from a road-legal point of view (due to emissions regulations differences between here and Japan) than changing the engine and trans, but I've heard the JDM trans simply won't fit to the USDM engine. Anyone out there know for sure?

As far as I know, I't be a direct bolt in fit.

I agree with Huck - it should fit. But I'd worry about the other little things like speedometer gear, selector cable, etc.

Besides that, I'd want some real, undeniable proof that the JDM transmission is significantly different and better than ours. I would expect that the only difference would be in shifting characteristics. If that's the case, you'd need the matching TCU, right? Or you could just replace those parts that make the JDM tranny different.

Just guesses. Sounds like a lot of trouble for little (if any) reward, when you can have your tranny built by expert shops in the US like Level 10.

Edit: Where is this evidence that you speak of?

Well, for one thing I understand that the AWD split is something like 40/60 front/rear, which I would prefer (I only went AWD because I had difficulty keeping RWD cars on the road in bad weather, so I am still partial to that drivetrain config). I will search for the thread I was reading about it in, there was a lot more. I also recall them saying the quality was better, but I don't recall exactly why.

Here's the thread. Harvey (oab_au) has scans of the manual in his locker.

Trans swap.
 

Yes the JDM type AWD is different, the main difference is the torque split, 36% front, 64% rear, tightening up to 50/50 and the way the rear wheels are gear driven. I feel that it would make a difference in the way the car powers through corners.

The US version, 90% front, 10% rear, tightens up to 50/50. The rear wheels are fully driven through the transfer clutch. While I have not driven a US model, I would expect it to exhibit front wheel drive characteristics.

There should be no problems in the swap. The TCU should operate the AWD the same way, as it responds to wheel spin. I am not sure, that the length of the box is the same, with the different AWD section, but it would seem reasonable, that they would keep it the same, or a different tail shaft would be needed.

The other difference is the final drive ratios, the US box uses 3.545:1, the European version uses the lower 3.7:1, so you would need the rear diff also.

I don't think the box is any different to the US version in any other way, so I would aim for a 94 model or later, to avoid the flaking facing problems.

All the best.

Harvey. ;)

Thanks Harvey, I'll continue talking to importers then, so I can be prepared for the inevitable in advance this time. I assume the fact that its from a RHD won't affect its operation in a LHD car, other than perhaps having the selector be "backwards", or more accurately mirrored right-to-left?

Out of curiosity and so I can focus my search on more likely areas, does anyone have the production/sales figures for the other markets (ie Europe, Japan, Asia, etc). I know I heard the folks in Australia didn't get too many, so I would guess thats probably not a likely place to get one imported from, but I have never heard figures for Japan even.

JDM production figures:

VL 1900 (91/09-93/11)
VE 2200 (91/09-93/11)
S40 300 (93/11-94/06)
S40II 300 (94/07-94/10)
S3 500 (94/11-95/06)
S4 600 (95/07-96/11)

Total 5,800

Less than 2,000 still registered in Japan. A few used JDM models have been exported to Australia, NZ, UK and Ireland. Plus there is one US model here in Japan.