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dannyracer6
09-21-2013, 10:32 PM
Ok, I got good information earlier about my carb stumble...I have a 4.5 PV, 72 Main jets, and a 30cc accel pump. Min 5 psi FP, pink accel cam, I have the accel pump adjusted properly, timing is correct for my engine at 37, It does not run lean now but I still have a stumble when I stab the throttle at lower RPM. It will stumble a bit at higher say around 3500 to 4000 but not bad. It will then do just fine. I am using a 28 squirter, the float is just below the site glass opening. and I have the off road needle and seat. Question, should I just live with this or is there something I am missing. It is a 500 cfm carb. It is way better than it was. The cam is a roller Crane, 42--82 range. any body have any ideas.

Dan

drtlvr
09-22-2013, 07:04 AM
I would try a bigger squirter if it runs good everywhere else.

7uptruckracer
09-22-2013, 07:32 AM
More fuel psi, and adjust your low speed idle circuit. 3.5 PV and white orange pump cam

84Dave
09-22-2013, 04:51 PM
With regard to the squirter, I'd try the opposite direction. Try about a #20 squirter. And use a 'stub' squirter. If the fuel is not being properly atomized out of the squirter, put a 1/16" drill bit, with tapered end, between your thumb and index fingers. Using only the tapered end, spin the drill bit to put a slight taper at the squirter outputs. That will tend to 'fan' the fuel output and atomize it much better. I've never been able to successfully use a #25 or #28 squirter on a 4412 2-bbl mounted on a 4-cylinder. -Dave-

let-r-eat
09-23-2013, 01:08 AM
ditto Dave's info. 25+ squirters are too big. Have you tried another carb?Try this:Put a flat plate and cover the opening of the carb slightly like your choking. Does it still stumble?