Jetting Help

[Banshee's ROCK!]

I just put high compression domes in my vitos head and k&n filter with the lid off i put the kit in and it freakin rips!!! with .040 over power pistons! But the problem is that it seemed as if i was still to lean on top with 300 mains because it kinda pops like its kinda lean or its running out of fuel. i drilled my mains out to 5/64ths of an inch and it kinda helped now the plugs dont look quite so lean actually they look perfect, but it still does it a little only at full throttle. one of my theorys is that now with all the flow my carbs are too small, its sucking the fuel so fast they cant keep up has anyone ever heard of this?

[Banchetta]

If your lean it will just take a while to rev out. If your too rich, then it'll spit and sputter......

[Rescuejeff]

What are your pilots and what type of elevation, and temp and maybe running a 330 main is good, let us know more...maybe Ducman or SDD will read this and have a better idea for you.

[Ducman]

Is the only thing that you changed was adding the head with high compression domes or did you also take the lid of the air box and/or add a K&N filter at the same time. What cc domes did you install, what is your elevation, and what octane gas are you running. List all of your mods.

 

I'm guessing you are too lean on the mains, and are geting symtoms of lean mains and/or detonation. With a K&N and lid off depending on what other mods you have I'd say a 330 main would be pretty close to what you'd be dialed at on the mains at sea level. Dont be drillin shit, you cant drill holes that small with any accuracy especially not enough for main jets IMO. Your carbs aren't too small unless you have have had some major porting done.

[Banshee's ROCK!]

I have a vitos head with 19cc domes and at the same time i put the k&n filter on without the box lid. vitos gave me a jet kit i drilled out mains tho but im going back to 290s and starting from there. i also am using 30 pilots. I am at sea level and i use 110 race fuel with 50:1 Klotz. I am going to take the jet kit out and put my proflo foam back on with the jets i had in and go just a little by little till i get it right. it might take longer but it then should be dialed in just right. I dunno its hard to describe the symptoms but when i figure it out i will tell ya guys. By the way we have a chassis dyno here at school and i will post my results! THANKS for the help but if theres anymore information out there please share it!