Re: 350 Scrambler Head on a 250 Monza
Posted: Sun Apr 26, 2020 1:34 pm
by gregwils
Thanks for all the responses, lots of great technical data. I am sure other future searchers will benefit from it as well. I will pull the head as soon as I have the opportunity.
Re: 350 Scrambler Head on a 250 Monza
Posted: Thu Apr 30, 2020 7:07 pm
by double diamond
A narrow case 250 Monza with a standard 24mm intake will have a 37mm intake valve. BTW, the port will be untouched casting. Higher specification models (SCR, Diana, Mk 3,etc.) use the same casting but the ports are hand ported and much of the valve guide support is removed. This is probably how your head with the 28mm port looks. Early Diana’s and SCR have 36mm intake valves. WC 350’s have 40mm intake valves. If your WC 350 head indeed has a green/white cam, that would be a pretty hot cam for a 250 and would require a high compression piston and megaphone exhaust to run well.
Matt