This is a dyno from one of my IRTB 1.8 street motors.This plot shows the effect of adjusting the overlap.This is a stock 99 with TEC-2, JR headers and FM N/A exhaust.This is a 2000 with TEC3, FMII turbo, FM downpipe and exhaust at 12 psi.This is the same car at 8 psi.Here are some of the origional plots of my 1.6 Autorotor setup at 12 and 14 psi.These are flow data from the same flowbench, by the same operator, of various Miata heads. These include stock, ported, ported to manifold, and ported with oversized valves. Interesting to note is the gain made by simply using a better shaped, stock size valve!
