Looking for inexpensive carb for trial running of Seal Major 30cc

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May 14, 2017
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Southampton, England
And I also agree with you :)
The point I was I was trying to make, but didn't quite express fully, was that any modifications to the air opening (the orifice in rotating barrel) would potentially also encounter dealing with the spray bar entering from the main / high speed needle valve side. So whether you somehow sleeved the hole to make it smaller opening, or somehow opened it up to make it bigger, you are going to have to deal with the restoring the original distance the low speed needle tip makes relative to end spray bar assembly. That distance is important because the low speed NV moves in & out based on the rotational position of throttle arm (within limits of mixture adjustment). The high speed / spray bar end is fixed. But this is carb specific, some have this spray bar assembly, I think like img 6146 in post #13. Others function differently & may lend itself to plugging off as you say.

Maybe I misunderstood the OP wondering out loud if that particular carb was a suitable match and/or how to go about sizing one based on displacement & engine type. So I think there are two inter-related factors: how big is the carb air opening & how is the fuel metered relative to that opening. Typically they are sized together. You can't put a 15mm dia carb on a 2.5cc engine & expect it to work. If he has the 'correct' orifice/carb/NVA size combination, then it makes little difference if the main NV is adjacent or remote. But I don't think he ever asked about NV position being a limiting factor or consideration?
On RC carbs and in particular cars, the choke area is reduced with inserts that sit in the top of the choke well above the barrel or slide, these work well and you don't have the problems that you mention with the idle needle.


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Jun 24, 2010
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Like so, right? That's exactly the direction I was going with my radial but chickened out in the end. Mostly because I just don't know much about RC car carbs. Maybe they are the way to go. I redesigned my manifold with a standardized adapter plate so I can try different carbs.