Jason Moyle Racing

@tim , yes , we did indeed . He didn't think the phenolic gasket would do a lot , strange IMo , I thought they were a good idea.

LOL now that sounds about right for Guy...if he hasn't tried it or recommended it then it isn't right    Guy and I have a bit of history....probably best you never mention my name lol

Back to the topic in hand.....the phenolic gasket is definitely not a bad thing IMO although if the cause of the issue is not heat tranferal from the cylinder head then it'll make no significant difference.

I would initially go back to basics as this is a condition that has suddenly occurred......if still running a dizzy check ign timing as from recollection the dizzy can work loose and a change in timing (retarded) would certainly cause the symptoms described.

Has anything else been changed before the event?  Plugs for example?  Typically Guy use to spec plugs one grade cooler on his high output engines, using a std grade plug if you have a concern with fuel would also cause some problems in higher ambients.

I have personally never been a huge fan of foam type air filter elements and I know for a fact that Jason isn't either!

Wish I could be of more assistance.

Tim