Mukini jets or jet drills

[FzerozeroT]

I need to get some 300-380 size main jets for the ol' RGV. I have a whole lot of 260's that I can get drilled, just been informed that they are around $12 each new, and i don't have the coin to buy 8!

Edit: yay for 500 posts!

[F5 Dave]

Drilling jets is a bit hazardous as they can end up flowing differently & you don’t really have any way of testing them. + you have to mark them carefully. On an RGV which gets a bit prone to seizing if you get too close to the wire is it worth frying a piston by going up a jet size to be safe & finding it doesn’t flow anymore?

[curious george]

Why do you need 8? Last I looked in mine, there was only one main jet each...
I'm guessing you are running premix, no airbox?
Unless you are runing very close to the wire, perhaps go 300, 320, 340, 360, 380, instead od 300, 310, 320, 330 etc.....
You will use different jest for each side anyway, and if you go one over, just make a note for next time.
My 2c anyway

[FzerozeroT]

kit pipes and premix are the only mods to the engine, I need 8 because you can't drill down jets and I'm gonna start at 400~ and work my way down on a dyno, also wouldn't mind getting 2X #30 pilot jets.. So close to racing, yet so far :(

[F5 Dave]

Cheer up, what about the powerjets & air jets?

[FzerozeroT]

I got a decent selection as the various carbs I've got (10) have been from different models, but they all seem to have 250-280 mains and #27.5 pilot. Except for the 450,460 combo I'm running at the moment.