Posted: Mon Aug 07, 2006 10:17 am
"Why do the books/manifold say 12 thou" - because they were all written in the days of leaded petrol! With the dreaded unleaded - I believe it's best to leave the exhausts at 15 to make sure the gap does not close up. The engine runs hotter - the exhaust valve is not so well protected with no lead - it gets hotter than ever. In fact A series engines run better with slightly larger valve gaps - but of course it's rattly at idle.
But everyone to himself - set 12 thou if you wish.
But everyone to himself - set 12 thou if you wish.