Hello, love CL, have found amazing info here that has helped me beyond what I could have hoped for. New to posting, and im aware of several posts on this topic, but it seems to there is just so much to consider on this topic. I'm hoping to find a straight forward approach, without having to do too much modification or adapters, atc. Anyway, to the point, I have been wanting to swap out my automatic transmission for a manual for a while. I simply want to swap in a manual, nothing fancy, it's a GE NA, 100% stock I really appreciate any help anyone could give me. Again I apologize for re-hashing this topic, but as I've said there's so much on this topic and I just want the most straight forward approach. Thanks again all.

 

Hello and welcome to ClubLexus!

Yes, there are many threads on this topic but in brief since you only want to stay 2JZ-GE naturally aspirated and swap to manual then your most straightforward swap will be to find either a 1992-1994 SC300 W58 ("toploader" extension housing type), 1995-1997 SC300 W58 ("tripod" type) or a 1993-1997 Supra MKIV NA W58 ("tripod" type) and go with that.

Avoid the Supra MKIII W58 (with an aluminum center sandwich plate) as it's not as strong as the SC/MKIV version and uses different tail shaft trans mount holes than the SC/MKIV version. It also has a mechanical rather than electronic VSS speedo drive. The shifter on these also does not come out as far as is needed in an SC.

Since you're in California and probably have a CA Emission chassis you should probably also look for a 1996 or 1997 SC300 M/T ECU or a 1996-1997 Supra MKIV NA M/T ECU that matches your emission type.

We have a database of SC300/400, Supra and other ECUs which are listed by part number here:
https://www.clublexus.com/forums/per...s-by-year.html

You can hunt for a 4.083:1 rear diff if you want to but I personally feel the SC300 Auto 4.272:1 rear diff provides a much more fun and usable experience (and it's the ratio that came stock on 1993-1996 Supra MKIV NA 5-speeds).

You'll also need an SC300 or MKIV W58 front driveshaft.

W58's are not always in perfect condition and if one that you can locate needs rebuilding I'd recommend Driftmotion or Marlin Crawler for the job.

An OEM SC300 M/T manual pedal set would have to be sourced used or you can use the kit made by XCessive Manufacturing.

.....

Your transmission tunnel will need modification in order to bolt the W58 in:

--For the 1992-1994 SC300 W58 with the factory "toploader" extension housing a "swan neck" type shifter is required. Either an OEM one from an SC or Soarer, a used SupraSport V2 or V3 short shifter or the Cube Speed short shifter. Even then the shifter location is further forward than on the 1995-1997 SC300 5-speed tunnels so the appropriate cutout must be made and you'll also need a dust and sound boot to seal it.

--For all "tripod" W58's you can use the Supra MKIV Manual transmission top tunnel for an extremely OEM installation or you can use Grannas Racing's kit that converts an Auto tunnel to a Tripod style tunnel. The Grannas kit provides a dust and sound sealing boot. The OEM Toyota Supra MKIV Manual tunnel conversion requires the same sound and dust boot parts that go with it from the Toyota parts catalog. That tunnel's part number is unique to the Supra but it's basically the same "tripod" transmission top tunnel part that came in 1995-1997 SC300 5-speeds and in all "tripod" manual equipped Soarers.

....

Now you can also just as easily swap in an R154, R150, R155, AR-5, CD009 6-speed or Tremec (each with their own unique requirements to set them up for an SC and JZ engine) but for a simple SC300 2JZ-GE naturally aspirated car that will be converted with a manual transmission I think a good condition SC300 W58 or Supra MKIV W58 will still be the best choice.

 

Really appreciate the information. Truly amazing community here, I do have one more (stupid) question then. I've had my eye on a transmission in a 2004 IS300 and wasn't sure if this is as applicable as the MKIV option. If not, I will go with another of your suggestions. Side note: Being a smog technician in California I'm not too worried about smog. However, it has always passed on its own and I intend to keep it that way, and I hate seeing lights on the dash so will most likely get the transmission ECU. Push comes to shove though, and it will pass. I (probably) have an unhealthy obsession with this vehicle and will do what it takes to keep it on the road. Thanks again.

 

Does the Grannas racing kit work for the SC as well? Looking on their website it only states that it works for MK4. Also it looks like it might be too tall for the shift surround or no? Are there any successful attempts on SC's on CL?

And 2nd, are the drive shafts from W58 SC's and MK4's the same? At least the front halfs? I was able to source a complete swap from an N/A Mk4 and I thought that the only component I'd have to replace is the front drive shaft as the MK4 and SC300's are different.

 

The IS300's come with a W55, not W58. I believe they are different gear ratios as well as the W55 being rumored to be weaker. There is also the issue with the placement of the shifter housing/shift arm which would not line up with an SC300. Your best bet is to go with a W58 from a SC300 or MK4 as Kahn stated

 

You're welcome! And as to what magicpants said above, the W55 will physically fit but is a weaker transmission than the SC300 W58 and MKIV W58. Even for a stock NA application it's better to use the SC/MKIV W58 in the heavier SC chassis. Also the W55 comes from the factory with an expensive dual mass flywheel... which can be converted to single-mass using W58 parts. Its shifter location I think may line up as all tripod shifters do but I am not sure about that. In any case it's not the ideal choice for an SC manual conversion. Even IS300 owners have been known to upgrade their own cars with an SC or MKIV W58 for better durability and strength.


It's good that you are a smog tech, then as it certainly helps. I just know how there is less leeway in the allowable limits for each model year compared to how things were before. And an appropriate M/T ECU will help with that as well as avoid any CEL.

There is no transmission ECU, just the main engine ECU which will either be M/T type or A/T type and in addition 49-state Federal Emission or 50-State CA-Emission for each transmission type. M/T ECUs just lack the circuitry which controls automatic transmission shift logic while the A/T ECU will throw a CEL code if there are no transmission shift solenoids present. Additionally the M/T ECUs have programming which (I may not be using the official and correct terminology here) acts as "randomized shift logic" which accounts for the human operator's unpredictable gear changes and pauses in between gear shifts... as to how the emissions controls handle this variable.

Generally SC300's with manual transmissions run and drive a bit better overall with a manual transmission ECU.

Since you have a 1997 chassis (which I assume is a CA Emission chassis?) then the M/T ECU for your car will be extremely rare. However there should be no difference in the actual tuning between a super-rare 1997 SC300 CA Emission M/T ECU and a much easier to find 1996 CA Emission M/T ECU. If you happen to have a Federal 1997 chassis then sourcing the right ECU is even easier.

Avoid 1995 SC300 M/T CA Emission ECUs for your purposes. They are oddballs in that they are still OBD1 but want to see four-wire heated front O2 sensors. Not what you want for an OBD2 chassis *or* for a 1992-1994 OBD1 chassis unless it's a 1995 SC300 CA Emission model.

In the "ECU By Model Year" thread that I linked above you will find the part numbers for nearly every 1992-2000 SC ECU for reference and hunting down.

Also I highly recommend getting an ECU with no capacitor service history sent in to have new OEM-spec capacitors installed. Tanin Auto Electronix still offers this service on a special request case by case basis and they QC test in one of their shop SC's. They have a main office in Wisconsin and a satellite repair office in San Diego.

SIA Electronics is another such ECU repair outfit but I'd recommend contacting Tanin first.​​​ They've been taking care of the SC community with our electronics for over twenty years now.

In most cases any ECU that is showing signs of malfunction can be saved and put back to totally normal operation by replacing old and worn out capacitors (however they MUST be the exact values AND brand that they were manufactured with.... all available from Mouser Electronics or Digi-Key. Repair service companies take care of those details but it's just good to mention here FYI).

....

Also just to mention something else about using the 4.272:1 final drive ratio: You may see that the output numbers are *ever* so slightly higher in each gear at 15mph and 25mph than is expected but they SHOULD be within normal limits. Supra MKIV NA 5-speeds from 1993-1996 all came with 4.272:1 final drives from the factory so this wasn't a problem for them with emissions. However the 1997 Supra MKIV NA 5-speeds (last model year for an NA manual just like the SC300) from then on came with 4.083:1 final drive ratios.

I mention this just in case it's ever an issue as to the 15mph and 25mph outputs that are expected within the allowable ranges. If it is then you can always source any 1992-1997 SC300 5-speed 4.083:1 rear end to swap in (or a late model 4.083 from an MKIV Supra NA or from a few model years of the mid/late 90's GS300 which also came with 4.083 rear ends). A simple swap of the rear diff companion flange is all that may be needed if you find a 4.083 rear diff from a GS300.

My 1993 CA Emission SC300 5-speed passed just fine with a 4.272:1 rear end swapped in place of the original 4.083 (using 275/40R-17 tires in the rear) but it might be more difficult with a 1996+ OBD2 SC300. I coudn't say honestly as it's such a minute difference.
....

I completely understand where you're coming from having an obsession with keeping your SC300 maintained and on the road. I'm the same way and went to great lengths myself when I had my 1993 model in California and will again when I drive it back there and re-register it. It can be a challenge but it's worth it keep one of these excellent cars on the road

Grannas primarily designs their kits for the MKIV Supra and IS300 but the same MKIV parts should fit an SC300 without issue since the transmission tunnels are the same. There is also a kit on eBay which converts an SC300 Auto tunnel to SC300 Tripod Manual tunnel in the same way.

In this case the front driveshafts for the SC300 W58 and MKIV W58 are the same. It is only after the (identical) center bearing where the rear driveshafts are different lengths between the two cars since the MKIV has a shorter wheelbase than the SC.

 

what exactly are you looking for from grannas? His clutch pedal fits the sc300’s and has been tested. His cd009 kits for the sc300’s and even has the right driveshafts. His customer service is top notch , I have the t56 mag kit, his 8.8 kit, and just ordered his manual rack and ultimate rear anti roll bar.

 

Once again, amazing info and advice here. Very much enlightening, and I believe I know how I will approach this now. First trick... anyone got a MKIV transmission and ECU for sale? Lol
Thanks again all, really appreciate everything. Wish all the best with 2JZ's.

 

One last (probably stupid) question. The differential and drive shaft is mentioned multiple times. So just to set mind at ease, when swapping in a w58, will there be any adapter or drive shaft and differential swap needed, respectively?

 

You will need the front half driveshaft from an SC300 or Mk4 Supra that came with a W58. You mate the front driveshaft with the rear automatic driveshaft that is in your car already. This will create the exact length driveshaft you need.

As for the differential, you can continue to use your stock diff which is geared at 4.27. Kahn states he prefers this ratio on N/A 2J's. The stock ratio that came in W58 equipped cars is 4.08 which is quite rare to find.

 

Im interested in the tunnel conversion from them. I think I am going to go ahead with that as opposed to welding in a tunnel.

 

^^ This as stated above by Magicpants

Again, the 4.272:1 ratio that you already have in an SC300 Auto is just what I preferred over the 4.083:1 ratio that came in my factory 5-speed. The 4.272 is the ratio that 93-96 Supra NA 5-speeds came with from the factory and it makes the driving experience a bit more lively with a bit more shifting being required (which I love) and additionally made the NA 2JZ engine more usable up in L.A.'s mountain roads with a more usable 2nd and 3rd gear in those situations especially. Highway revs at 70mph are around 2800rpm in 5th with the 4.083 and 3000-3100rpm @ 70mph with the 4.272. Also... highway passing power is improved with the 4.272.

Yes, it does cause higher highway revs on the highway but still I did many road trips with that configuration and I still have to say that I preferred it. That being said, you can have a milder experience that is basically "stock" for a factory 5-speed, swapping in a 4.083 rear end from an SC300 5-speed or late 90's GS300 or 97-98 Supra NA (both of which which also came with the same 4.083 diff and which just required a companion flange swap) is the other option.

I detailed my 4.272 diff swap for my original GE engine and all that goes with it in this thread: https://www.clublexus.com/forums/per...rset-swap.html

^^ In my old thread I also show how to install and adjust a Yellr Yellowbox V4 (or V5) speedometer accuracy corrector into any SC. This is very useful for making your speedometer read with near perfect accuracy again when you have changed to a different style transmission, changed to another rear diff final drive ratio and even if you've changed to a different overall wheel and tire diameter from stock.

It takes in the pulses from the 3-wire VSS signal coming off the A340, W58, R154 or other transmission (if that transmission has an onboard VSS like Toyota transmissions do) and allows you to send back out an adjusted pulse signal that, after you road test and adjust the percentage you need, will make your speedometer accurately display your actual road speed again like it does when your driveline and wheels and tires are stock.

And just FYI, the SC's odometer is largely unaffected by this since it is comprehensive taking its mileage readings from both the transmission VSS sensor *and* from the front wheel ABS speed sensors.

....

Also, for some years with my stock W58 transmission so as to maximize the impact of shorter gearing I paired this with the factory Supra MKIV TT rear tire size of 255/40R-17 with 235/45R-17 up front. This actually gave an ever so slightly *smaller* rolling diameter in the rear versus the front. It was fun but eventually I settled on 245/45R-17 in the front and 275/40R-17 in the rear with the 4.272 rear gears. It was still a very fun and lively NA setup.


If you want to do the M/T tunnel swap you should focus on acquiring a Tripod style W58 from a 1993-1997 Supra NA or from a 1995-1997 SC300 5-speed. Its shifter lines up perfectly with it.

The tunnel P/N is 58261-14010. The rest of the parts (dust boot gasket, etc.) are on Driftmotion's site. I haven't got those part numbers handy at the moment.

Dmitry (username "97-SC300") has a very detailed writeup in his build thread showing how he did this tunnel swap for his V160 transmission conversion but unfortunately all the pictures were uploaded to another image site and seem to have been lost. Nonetheless his text descriptions and detail are still available to research:

https://www.clublexus.com/forums/per...s-of-pics.html

 

so I have his tunnel conversion as well. When you look at the quality of his work it’s just amazing. I haven’t installed it yet, but he provides a printable template so you’ll know where to cut. Once it’s cut out , you use some seamsealer to make it air tight.with that being said, I’m not sure where the shifter placement is for a w58 Vs a t56

 

Dmitry's work is stunning in quality. I saw his thread when the pictures still worked and the work was incredibly well done! Yes, seam sealer after the few welds that are needed (as I recall) makes it a perfect air tight seal. I forgot that he provided that template-- I'll have to get it from his thread.

I have the same transmission tunnel part as well in case I ever swap out my MKIII R154 for a later R154 "tripod" or T56 Magnum transmission. I can tell you that a W58 "tripod", R154 "tripod" and V160/161 all have their shifters come up in exactly the same place which the MKIV manual tunnel matches (which is the same as the later SC/Soarer late model manual tunnel).

I believe that Joel Grannas has a custom remote shifter assembly that he designed specifically for the MKIV Supra M/T tripod tunnel opening so as long as you're using that tunnel part or a conversion kit that changes an Auto tunnel top to have a "tripod" style opening and location then you should be fine.