Need Carb Help

[aellerb]

Just installed new carbeurator on my boom Vader. When I run the motor the carb makes a loud noise. When I run down the road the carb sounds louder than the exhaust. Any ideas on what would cause / fix this? Thanks in advance!

[daytonacat]

thats an easy one guy.
That is INTAKE NOISE is all.
You are hearing the air being sucked in to the carb.

If you got a buddy with a truck or car with a V8 in it,(older vehicle is better for this) have him remove the air intake cover, start the vehicle and pop the gas pedal a few times real good. You will hear a nice throaty sound coming from the air cleaner assembly.

it is nothing to worry about at all.

It is just another source of noise is all.

Carl

[Megadan]

Originally Posted by daytonacat

thats an easy one guy.
That is INTAKE NOISE is all.
You are hearing the air being sucked in to the carb.

If you got a buddy with a truck or car with a V8 in it,(older vehicle is better for this) have him remove the air intake cover, start the vehicle and pop the gas pedal a few times real good. You will hear a nice throaty sound coming from the air cleaner assembly.

it is nothing to worry about at all.

It is just another source of noise is all.

Carl

Yep, I second that opinion, sounds like normal intake noise to me.

If you want the ultra nerdy explanation, you are hearing two things. When the slide first opens you hear the increase in vacuum across the slide and venturi . The secondary part of the intake noise is you experiencing the anode of the intake harmonic wave as it bounces off of the intake valve when it closes (the node) and the shockwave reverts back out the inlet of the carb to open air (anode).

You can actually hear the intake resonance wave at its strongest in a specific RPM point in the curve, usually close to torque peak,
You can also visibly see the waves with an open carb inlet. This video actually shows it quite well. You should also hear some familiar noises.