I realize this is an old thread, but I thought I'd shed some light on the issue. The fact of the matter is, Toyota bases chassis codes on 2 things: model revision, and engine type. Then there is what is in the VIN, which is used to distinguish between trim levels (turbo/NA/etc). W1 = 1st Gen MR2 W2 = 2nd Gen MR2 W3 = 3rd Gen MR2 A7 = 3rd Gen Supra E8 = 4th Gen Corolla Now of course the first letter added on is easy, it's just the engine family code. AW1 = 1st Gen MR2 with A-series engine SW2 = 2nd Gen MR2 with S-series engine ZZW3 = 3rd Gen MR2 with ZZ-series engine MA7 = 3rd Gen Supra with M-series engine GA7 = 3rd Gen Supra with G-series engine JZA7 = 3rd Gen Supra with JZ-series engine AE8 = 4th Gen Corolla with A-series engine Finally, the hard part, the last number, Toyota will have a "base" number that the chassis is, usually this is the model with the lowest engine family revision. Same engine family revisions get the same final chassis number. AW10 = 1st ...