Just picked up a new project car, an '85 Dodge Omni GLH Turbo (Goes Like [censored]) with the 2.2L turbocharged engine. Updated to Turbo II specs with higher output turbo, intercooler, MOPAR computer & cam, and making around 20psi of boost (a tad over 220hp/300ft-lb torque). I was told it has the upgraded transmission over the original. My problem comes when researching what to put in the gearbox. Several sites say that 5w-30 engine oil was used originally, leading me to believe that a lighter-weight GL-4 would be better (similar to earlier Hondas). The AMSOIL guide says to use Synthetic ATF for the manual transmission, leading me to believe that a synchromesh-type fluid can be used. Then on other performance turbo dodge sites, they use regular GL-5 oils in 75w-90 weights. Too many choices! Any real-world experiences? This will not be a daily driver, but a track/autocross car...different animals--- autocross will see cold-start with little to no warm-up and 100% thrashing on it, while track racing will be warm-temp with plenty of warm-up but much higher trans/engine temps and loads over a longer period of time(20-30 minute sessions). Thanks!