Toyota Supra Engine Question

[2jpowered]

Originally Posted by l_o_t_s_r

I'm new to this forum and not very informed on Toyota Supras I'd like to know what if any horsepower difference there is between the "American" Toyota Supra Twin Turbo(being the ones sold in USA) and the "Import" Toyota Supra Twin Turbo(being the RHD Supra), if I remember correctly the American Supra is rated at 320hp. and are the stats posted on most sights correct for quarter mile time stock for the domestic Supra being around 13.6 seconds? I'm looking into getting a supra in the future and would like to learn more about them and find out how accurate this information is.

As like what supragirrl said, the differences are the turbochargers(ct12s), the injectors(440vs550cc), ecu, and the egr system. Japan rated that car at the time as 280ps because of a "gentlemens agreement" to not start horsepower wars. In actuality, both u.s. and jdm supra tt dyno (dyno dynamics) around 270-280rwhp when in good condition in factory form. So basically in stock form they are slightly "identical". When modifying past 400rwhp on the jdm version, they usually swap in the stock export 550cc injectors and ecu. To be a little more specific, the jdm ct12b's are a .42 a/r turbo housing. The major and minor of the ceramic turbine blades are 60mm and 48mm and the compressor side is 62mm and 39mm. For the U.S. ct12b's they use a .53 a/r turbine housing. The major and minor are 52mm and 44mm for the steel turbine blades and 58mm and 39mm for the compressor side. The U.S. spec supra tt is only capable of around 540rwhp on the factory 550cc injectors, and thats at 80+% duty cycle(pretty much maxxed out). The factory U.S. spec turbochargers are only capable of around 490rwhp(give or take a few) as the turbos are out of its efficiency range past that. (there are no known compressor maps for the ct12b's released. But there are similar sized turbos out there (all old style, very similar)with compressor maps that can be used as a rough guide) The sweet spot(and daily driver reliability) for the tt's imho are around 18-20psi(Ive seen 25psi, but it had cams,nitrous and head work made like 500+rwhp), anymore is just heated charge air(got dyno graphs and air temps at diff. psi levels). I have pictures (couple different cases)of overboosted U.S. ct12b's that came apart due to insanely high shaft speeds that it wasnt meant to reach.(20+psi=max boost). Just my fifty cents.