3.5 is the best final drive imo the other is to long unles you have some big big hp, 90 terminal is very poor chipped car maybe but well done for trying.what was the topspeed then on full boost?
tim
i did a top speed run on the low boost settings and my clock was showing 140mph and the timing gear showing something like 127-128 then i backed off as i was too conservative to take any risks