Learned Brethren,

When we first started the "new" engine upon installation, there was no cat or muffler installed so it sounded a little loud, like a stock car, but ran at a steady pace.  Now we have the exhaust in place it sounds like a Vanagon ;o))

But what is unusual is as the thermostat opens the engine revs slightly increase - then drop to idle - then rev a little higher than the last time - then drop down to idle - then rev higher than last time - and so it goes on and on getting more revs per cycle.

Any suggestions where to look for a reason for this?

Puzzled Peter Marsh
Naples.