Posted By: jyrki
Carb identification? - 08/07/22 12:30 PM
Anyone recognize this carburetor I have in my car. It has absolutely no markings anywhere. It seems like it's anodized gold, and is a typical Holley style. The fuel inlets are the same as in some Demons I think. With blind power valves and to me seemingly large 91 & 93 jets.
Posted By: Tig
Re: Carb identification? - 08/07/22 12:37 PM
I've never seen one in person but I believe this to be a "Pro Comp" carb, Chinese version of a 4150.
Speedmaster appears not to have the screw in bleeds, but again I have no experience with either
Posted By: B1MAXX
Re: Carb identification? - 08/07/22 12:53 PM
I thought procomp and speedmaster was the same company
Posted By: Tig
Re: Carb identification? - 08/07/22 01:06 PM
I thought procomp and speedmaster was the same company
Correct, Procomp changed their name to speedmaster around 2014.
Posted By: jyrki
Re: Carb identification? - 08/07/22 01:13 PM
Thanks! Seems like one. There doesn't seem to be any numbers anywhere, so it's kind of hard to judge what kind of jets should be in there. The size is supposed to be 850, but I have no idea weather it's true or not. Anyway, for that size, 91&93 jets seems awfully big, and according to the plugs it runs rich = black plugs. And the idle screws can only be open about 1/4 turn or it's too rich. I think I'll drop the jet sizes 3 in the rear and 10 in front, and install a power valve in front. See how that affects the idle, or do I have to try to change the idle air bleeds to bigger size.
Posted By: B1MAXX
Re: Carb identification? - 08/07/22 01:26 PM
Jetting won't effect idle circuits.
Posted By: Cab_Burge
Re: Carb identification? - 08/07/22 03:13 PM
Jetting won't effect idle circuits.
Shouldn't affect the idle circuit UNLESS the throttle plates are open far enough to expose the transition circuits on some carbs
Posted By: B1MAXX
Re: Carb identification? - 08/07/22 04:04 PM
Transition slots are still from idle circuit. Idle feed restriction is the only "jet"on that side.
Posted By: jyrki
Re: Carb identification? - 08/07/22 06:17 PM
Ok. Anyway, I'll put in smaller jets all around + the power valve. Then I think again if I want to play with the idle restrictions. I think it was way too rich overall. Next weekend we'll see how it reacts, weather permitting.