I have assembled manifolds and sport exhaust on the car and after that it has begun shooting in the muffler when it runs downhill.
Requires this exhaust system another ignition timing, or is it the case that any misfire setting become more audible with the sport exhaust??
I know that it shall have 10 degrees pre-ignition, but should the ignition be measured by a particular rev. speed or should the vacuum to advancing mechanism be disconnected?
Cylinder no. 1 was the one closest to the flywheel?
Best regards
Terje
Ignition timing is 10 degrees BTDC idling (hot) with vacuum pipe disconnected. Best idle I've found is 900 rpm but don't rely on the Tachometer in the car as they can be inaccurate. No.1 is next to the flywheel as stated.
As a general rule popping in the manifolds can be due to mixture strength - too lean and it will spit in the inlet and too rich will cause popping in the exhaust. However, check that the gaskets between manifold and head are air tight too. A manifold gasket leak will also cause trouble.
Since every engine can be slightly different, sometimes you can get a better set up with the timing a degree or two advanced or retarded, and this is best done on a rolling road, but without access to one of those you could try it manually on the road.
Roy