Stock vs AM carbs

[Alex Barker]

I've seen a lot of threads about single vs dual and smaller vs bigger size but I can't find anything about how thrust, full spec, dasa and other aftermarket carbs compare to stockers. What makes them so much better and more expensive? Im not in the market for anything currently just trying to learn!

 

[mikidymac]

Very basically they flow more fuel and air. They also atomize the fuel differently than stock which can help with the larger bores.

As far as performance your engine can only use so much air and fuel so let’s say you have a stock 701 and you slap a big set of AM carbs on you will actually loose performance since it is too much air and fuel and your engine won’t have enough vacuum signal for the carbs to work properly.

Another big generalization is smaller carbs make more bottom end and larger carbs are more for high rpm and top end power.

 

[Alex Barker]

That makes sense, but if all they do is atomize better and have better flow why are there different options of the same size carb? Is there that much of a difference between them? People seem to like certain carbs, is that just because of brand loyalty or is there actual differences you can feel between high dollar carbs of the same size?

 

[TheBuzzard]

oh you can definitely feel the differenced. with high dollar carbs, there will be less pressure on your ass cheek, when your much thinner wallet is in your back pocket.
in reality, you should just leave the wallet out of your pocket, since there aint going to be any money left in it anyway. you wont even notice the difference in wallet thickness when you sit down tho, cause you butt will be very sore from it getting hammered by the carb guy

 

[smokeysevin]

My understanding is that the aftermarket carbs are basically upgraded versions of the sbn. Mostly better manufacturing and quality control which should mean they are easier to tune since the ports and fittings are better machined.

Another difference is the actual fuel outlet style, some use spray bars or "bomb sight" style nozzles in the venturi.

I don't know enough about them to be more specific than that.

Sean

Sent from my LM-G710 using Tapatalk

 

[Alex Barker]

My understanding is that the aftermarket carbs are basically upgraded versions of the sbn. Mostly better manufacturing and quality control which should mean they are easier to tune since the ports and fittings are better machined.

Another difference is the actual fuel outlet style, some use spray bars or "bomb sight" style nozzles in the venturi.

I don't know enough about them to be more specific than that.

Sean

Sent from my LM-G710 using Tapatalk

I didnt know they go through them and machine them better. Obviously the better the air and fuel gets atomized the better the engine will respond, is there any one way that is the best for fuel supply? For example is the spray bar better than the traditional bomb sight?

 

[smokeysevin]

I didnt know they go through them and machine them better. Obviously the better the air and fuel gets atomized the better the engine will respond, is there any one way that is the best for fuel supply? For example is the spray bar better than the traditional bomb sight?

Sorry if I confused you, the high end aftermarket carbs are just made with higher quality parts to start with while the clones and oe parts have looser tolerances.

Sean



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[Alex Barker]

Sorry if I confused you, the high end aftermarket carbs are just made with higher quality parts to start with while the clones and oe parts have looser tolerances.

Sean



Sent from my LM-G710 using Tapatalk

Gotcha thanks!