850XP body with thin shafts .120 N&S best on 750+ HP?

[NXBOY]

Should flow around 930 or so CFM on a 521 with Max of 7000 RPMs, Is the .120 N&S Close in size? Thanks

[rustbucket79]

If the fuel system is up to the task either the .110 or .120 needle and seat will do the job.

[NXBOY]

Thanks, just figured bigger N/S might have to run lower fuel pressure and need float mod to open more.

[rustbucket79]

I’ve never had an issue with single carb setups making north of 800 on gas.

[ClassAct]

Thanks, just figured bigger N/S might have to run lower fuel pressure and need float mod to open more.

If you want to lower your fuel pressure (and you should) then use BLP .120 bottom feed needle and seats. 4-4.5 psi is all you need. That’s all I’m using any more.

[NXBOY]

Was plan on going eventually E85 but lowering compression on build and back to Premium Fuel, sure hope it don't disappear , down to one place that sales it in town. I got friends helping to get it track once so trying to make it right, thanks