|CT20||82-90+||3T-GTEU, 22R-TE, 1C-T, 2C-T, 2L-T|
|CT26||84-96+||3S-GTE (some), 7M-GTE, 12H-T, 13B-T, 14B-T, 1HD-T|
|CT12||85-90+||1G-GTE (two), 2E-TE, 3E-TE, 1N-T, 2C-T|
|CT26 ceramic||89+||3S-GTE (some)|
|CT12A ceramic||90+||1JZ-GTE (two)|
|non-water cooled||water cooled|
early 3T-GTEU (82,83,?)
2C-T (until 86)
2L-T (until 86)
late 3T-GTEU (?,85)
presumably all post-86 applications
CT20 has slightly worse lag than a Garrett T03 with 0.63 A/R and 45-trim compressor. However, the Garrett poses a much smaller restriction to the exhaust due to 40% larger turbine inlet. Also, this Garrett compressor has a maximum intake air flow for about 240hp.
CT26 is a much improved unit featuring a divided turbine housing for better response. It is also water cooled.
Some CT26's in MR2's had ceramic turbine wheels for further improved response.
Maximum play for CT26 (probably about the same for others too): axial 0.13mm radial 0.18mm
CT12B is manufactured by Hitachi for Toyota. Pretty good turbo when it comes to efficiency and response, but they seem to fail a lot on the Supra TT...