Jetting the Blaster on U4.4

[dericsdad]

Doing some tuning on the Blaster for Deric's 2012 season...

New CT Pipe and 35mm PWK A/S Carb. on the Blaster and gonna try the new VP U4.4 in it. Have 165 PSI Comp. and Ran a Blend of CHP Last year which is close to the same but a little more Oxygenation.

This new carb. came with a 160 Main jet and 48 Pilot. Down to a 42 Pilot, Air screw out 1.5 turns, needle happiest in the center clip, and all the way up to a 190 main jet! It just barely sputtered at WOT with a 195 main.

Amazing I had to go that big on the main but that seems to be where it is happy...

Has anyone else had experience running the VP U4.4 in a 2-stroke or Blaster???

This thing reminds me of riding my brothers 250r 4-trax race bike back in the day now!

[greenmachine70]

Too much work to run the fuel. IMHO you won't see enough gain. Now you will have to drain carb after every race. What was your main on 110 or race gas? What cylinder are ou running?

[dericsdad]

Yup... switching to c-12. Just runs too hot on the u4.4. too bad, it's a rocket for the first lap then gets warmer than it should even with jetting as rich as it can stand without sputtering.

VP says just too much heat in these air cooled motors for it. They even told me to run C12... the second time i called:confused: