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Author Topic:   carb loading in corners
Alan Rat
posted August 16, 2003 08:02 PM
I'm running hobby rules that limit carb to a Holly 1850, single inlet,vacume secondary.M y problem is it loads up in the corner.then sputters comming off. picks up fine on straight.Plug check is lite tan after a pull down the straight. I'm running 71 jets, 3.5 power valve, it has a whistle vent, and float level is correct. Engine is 355,550 lift cam,alumium intake and headers. Can any one offer help or where to look for help? Thanks

posted August 16, 2003 08:43 PM
Try setting the floats down a little bit below the hole might be sloshing out of the vent.

posted August 16, 2003 08:47 PM
It's a simple design limitation of the side hung float bowls in the 1850 carb. That's what those side hung floats will do when fuel is loaded up sideways due to cornering forces.
I'm not sure there's much you can do. The side hung float bowl is not meant for oval track racing for just that reason.

I've seen some ingenuity at work, however, with some fancy little teeny baffles to help limit fuel side loading, but they also can shift or fail and cause a float to hang open (instant DNF).

Hope that helps, wish I had a simple answer...


posted August 16, 2003 11:56 PM
we work with the 1850 alot try 76 jets in front 80 in rear...#31 squirter..and use short yellow or tall yellow rear springs... hope this helps...Kp will have the parts if you need a 6.5 power may be opening a little slow with the 3.5,causing a bog from to much air.hopes this helps.

[This message has been edited by mongo21 (edited August 16, 2003).]

Alan Rat
posted August 17, 2003 10:04 AM
Thanks guys for the input. Does any one know a web site that offers race carb tuning tips?

Earl Parker II
posted August 17, 2003 02:24 PM
KPLugnut is exactly right on the fuel bowl design. The solution, if the rules allow, is a center-hung fuel bowl. In addtion, you want to make absolutely sure you have no more than 6 psi. of fuel pressure at idle. If you do, you'll need to plumb a fuel pressure regulator (Holley PN 12-704 seems to work well) into the fuel line per the enclosed instructions, then set the pressure at 6 psi. This is a must for maximum acceleration any time a .110" Viton-tipped needle & seat is used (which comes standard in the 0-1850).

Earl Parker II

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