need help. at what fuel ratios can I achieve max power or economy? also I have a friend whose second generation rx-7 fluctuates between 1400-1600RPM at idle. I am almost certain that the problem is with the throttle position sensor resistance. has anyone had a similar problem? if so, your help is greatly appreciated.

 

as for AF its quite hard to determine a BEST, as all A/F are a combonation of safty VS power... for example a turbo car running a leaner AF will make alot more power but will run the risk of detonation and damaging the engine