HarperRacingBangkok
Member
"Fitting a Toyota 1JZ A340 transmission onto 1UZ." That's the search term I wish would have yielded some results when I was in the process of building my combination.
I had a race car with a 1JZ (actually a 1.5JZ) and racing automatic and torque converter when I decided to "add two cylinders and swap the turbo for a supercharger." I swapped in a 1UZ and it all bolted up . . . or did it? NO it didn't. Here are my lessons:
The 1JZ and 1UZ bell housings have the same trans bolt pattern, so a 1JZ trans will bolt right up . . . . they look look the same . . . . .
. . . but the 1UZ bell housing is taller/thicker than the 1JZ bell.
If you plan to use the same 1JZ torque converter, like this high stall MV Automatics unit, and bolt it up to the 1UZ ring gear/flex plate, you need to do a couple of things to make it all work:
You need to make a "drive ring," like the one above, to space the torque converter so its internal splines properly index with the trans input splines. As you can see, this drive ring allows one to bolt the converter to the drive ring with one set of holes, and then bolt that assembly to the ring gear with the other . . . or as I did, since I had already modified the 1UZ flex plate to accept the 1JZ torque converter bolt pattern (less than 1/8" difference, as depicted below), I used three high quality bolts all the way through the flex plate and through the drive ring into the torque converter mounting pads. A last piece, not shown, is an extended "pilot bushing" for the end of the crankshaft that captures the knob at the end of the torque converter to supply support to the input shaft/torque converter assembly.
The 1JZ torque converter mounting bolt pattern is not exactly the same as the 1UZ torque converter bolt pattern. As can be seen above, the bolt circle is slightly smaller in diameter.
I will not provide the exact measurements for the thickness of the drive ring or the amount the 1UZ flex plate mounting holes need to be modifies because I feel a builder should do this themselves . . . because there may be variations I am unaware of.
If you have found this posting because you have a 1JZ trans and torque converter and want to use it in a 1UZ swop, you now know that it can be done. However, as several racers and 1UZ experts have suggested: it might be easier to just sell your 1JZ trans and converter and purchase a purpose built 1UZ race trans and torque converter.
I had a race car with a 1JZ (actually a 1.5JZ) and racing automatic and torque converter when I decided to "add two cylinders and swap the turbo for a supercharger." I swapped in a 1UZ and it all bolted up . . . or did it? NO it didn't. Here are my lessons:
The 1JZ and 1UZ bell housings have the same trans bolt pattern, so a 1JZ trans will bolt right up . . . . they look look the same . . . . .
. . . but the 1UZ bell housing is taller/thicker than the 1JZ bell.
If you plan to use the same 1JZ torque converter, like this high stall MV Automatics unit, and bolt it up to the 1UZ ring gear/flex plate, you need to do a couple of things to make it all work:You need to make a "drive ring," like the one above, to space the torque converter so its internal splines properly index with the trans input splines. As you can see, this drive ring allows one to bolt the converter to the drive ring with one set of holes, and then bolt that assembly to the ring gear with the other . . . or as I did, since I had already modified the 1UZ flex plate to accept the 1JZ torque converter bolt pattern (less than 1/8" difference, as depicted below), I used three high quality bolts all the way through the flex plate and through the drive ring into the torque converter mounting pads. A last piece, not shown, is an extended "pilot bushing" for the end of the crankshaft that captures the knob at the end of the torque converter to supply support to the input shaft/torque converter assembly.
The 1JZ torque converter mounting bolt pattern is not exactly the same as the 1UZ torque converter bolt pattern. As can be seen above, the bolt circle is slightly smaller in diameter.
I will not provide the exact measurements for the thickness of the drive ring or the amount the 1UZ flex plate mounting holes need to be modifies because I feel a builder should do this themselves . . . because there may be variations I am unaware of.
If you have found this posting because you have a 1JZ trans and torque converter and want to use it in a 1UZ swop, you now know that it can be done. However, as several racers and 1UZ experts have suggested: it might be easier to just sell your 1JZ trans and converter and purchase a purpose built 1UZ race trans and torque converter.
