More of an FYI than anything else...

As we add this kind of info it can only help others as they figure out basic jet sizes and such based on their application.

My Engine:

Triple Mikuni 44PHH bought new from Mikuni USA

(as such fitted with all stock jet/venturi sizes)

fresh E88 head fitted with larger N42 valves & stock cam

fresh F54 L28 stock bottom end

I had noticed a little bit of detonation in 3rd and 4th at WOT

I swapped out the main jets (150) to the next size up (155) and that seems to have cured the problem.

Incidentally my 120mile roundtrip commute is a good time to figure out average MPG too:

With a 4.11 rear end and the stock 4spd I run between 4000 and 4500rpm on the freeway. I know that 4000rpm in 4th = 69mph.

With the 150 main jets I was getting a consistent 20mpg on the freeway

With the 155 main jets that's dropped to 18.5mpg

Hope this is of some help to someone.

-e

Eric, I moved this into the tech forum... good info!