Smokeywolf 1 Posted September 6, 2017 I'm new to the world of flat heads as I have just purchased a 54 Starchief with L8 engine. My problem is this. The Engine holds back and does not freely rev. Getting to 45 mph is slow but reasonable but will not accelerate much more than that. So what could it be? First thing I noticed was the exhuast had a small blow. Causing the air fuel mixture to be incorrect. New gasket fitted.= No improvement in performance. Next was possibly weakened spark at higher RPM . Petronoix igniter and coil fitted = very small improvement. Ignition timing checked looked miles out so readjusted the timing to between 3 and 5 deg before TDC.taken from the Harmonic blancer. A road test found this made thing wrose. I'm not running 19 deg BTC and can get 50 at a push. Still not working correctly. Other Observations : While running the engine I noticed the throttle connecting rods becoming very hot to the touch!! Spark plugs all have a small spark but all working Advance and retard appears to all so be working. Any ideas will be greatly received. Quote Share this post Link to post Share on other sites
Tinindian 892 Posted September 6, 2017 Plugged exhaust could cause all of the above. Undo the exhaust pipe and go for a short noisy test drive. 2 Quote Share this post Link to post Share on other sites
