Sc400-2JZGETT Conversion

[UCF3]

To all:

Wanted to know if anyone had converted the SC400 to the 2JZGETT engine from the Supra Turbo? I'm interested in finding out what modifications will be necessary in the engine bay and transmission bay for the conversion.

[pauldridge]

I have installed a Supra TT engine in my SC300, and documented the process on my website. Can't speak for sure about the SC400, but have to believe that most of the fitment and interface would be similar.

[UCF3]

Was there anything new you had to add to the SC300 for the Supra TT conversion? Specifically near the chassy, moving some rods or pipes, anything that prevented you from making a straight drop? By the way, which year Supra did you get, and what speed did you get it in? I'm curious since there is a 1992 SC300 that I plan to purchase soon, and the conversion is on my list of things to do to this car.

Finally, how much did it cost you for the conversion?

thanks

[pauldridge]

Whew, That's a lot!

Not trying to make a sale.. but EVERYTHING you need to know is covered in my conversion manual... however, I'll try to answer your questions best as I can:

The TT engine fits with NO modifications into the SC300 engine bay. There is even an opening already there as provision for the intercooler pipes, and place to mount the intercooler in the right side of the forward compartment.(thanks to the Japanese Lexus Soarer with the turbo engine).

The actual year of the Supra engine used is pretty much immaterial, they are all virtually identical. It is the ECU and the wiring harness that is somewhat different with the OBDII diagnostics, and that system can be somewhat more troublesome to connect up. Best to stick with a 1995 ECU and harness, or earlier.

Also, it doesn't matter whether the engine was used originally with auto or manual, either will mate up with the stock Lexus transmissions(s).

I used the Lexus 5-speed, which is plenty strong for the job. Most sources seem to think the automatic is a bit weak to handle the extra power.

Cost? Can vary wildly... if you can get a complete Supra engine/intercooler, MAF, Oil Pump, Fuel Pump, harness, ECU, radiator, then your other costs will be less than $1,000. Obviously, any missing pieces from the Supra side will increase the overall costs.

Hope this helps!

Phil

[UCF3]

That helps with the basic understanding on what needs to be done and the average cost.

You mentioned 95 or earlier. Won't the later ones work with the old transmission?

I would like to get the 6speed since it's available, and in the US. Easier cost wise. The 6speed is also better for the twin since road racing wise, the extra gear will help moderate speed for the way I dirve.

thanks for the input.

[pauldridge]

The engines themselves are physically virtually identical for all MKIV models from 93 through the last ones in 98. It is just the ECU, and most likely the corresponding main wiring harness that differed when Toyota started including the OBDII diagnostic software. My own engine is a '97, but running the older, pre-OBDII ECU. I haven't had personal experience with the OBDII, it may interface just fine, but several Supra forum posters seem to indicate that the complexity increases a good bit when making a conversion.

[SoarerTwinTurbo]

im going to be buying a 1992 lexus sc300 5 speed with 80k miles locally this weekend. I just sold my 1991 toyota mr2 turbo with 78 k original miles to buy this. I really want to do this swap very soon. My brother currently owns a 1998 twin turbo supra so i am very familiar with the 2jz-gte engine and its potential. Id like to know more about the transmission fitting up with the supra tt engine and more on this swap too!

[pauldridge]

Bear in mind the bottom end of the Supra GTE TT engine is virtually identical to the Lexus stock, with exception of some peripherals. Both the Lexus transmissions will bolt right on with no modifications. Some folks think the automatic is a bit weak to handle the extra power, and particularly if you tweak the TT engine beyond its stock output (who wouldn't.. it's so easy?). The 5-speed manual, however, is pretty bullet-proof. Mine has gladly handled the 450HP I've thrown at it over the past 15k miles.

The stock Lexus clutch will FIT, but it won't last for 3000 miles with any appreciable boost from the TT engine. After some trial and error, I found that a heavy-duty Toyota truck clutch unit did the trick, and holds the torque without complaining.