Intake Resonator

[YetiWoodz]

Lol. I don't know what its called. CDI, CVI?

 

[Chainlube]

I use the same kind of tach for tuning my chainsaw, I only paid ten bucks CAD.

 

[YetiWoodz]

So yeah, whoever wants the exact dimensions for a custom tuned intake resonator and what parts to use, look at my post on page 2.

A test that was done on one of the webpages I linked, the intake resonator will increase throttle delivery at 1/4 throttle 6% at resonant rpm. The boost is 12% at 1/4 throttle and 8% at 3/4 throttle. It will also give you a more linear powerband by eliminating trough rpms. It also almost completely defeats the need for a reed valve because it sucks in the air that exits the engine through the carb.

 

[YetiWoodz]

Just to clarify, the STOCK carb/intake does have a valve that opens and closes or something that stops the air from entering/exiting intermittently right?

 

[YetiWoodz]

No it has no reed valve. It's controlled by the piston. AKA piston port 2 stroke.

Ok, so the stock intake lets air back into the carb, but the air going into the cylinder does get stopped intermittently right? Allowing a boost bottle to work in a stock intake?

 

[YetiWoodz]

How comes I got a peak rpm of 5850, and my meter says its at 349 hz, but if you convert rpm to hz, it should be 98hz? I guess each engine has a different frequency to rpm "multiplier" because different engine have different tones maybe??

 

[HumanPerson]

Could casting flaws, which IMO would be different for each engine, cause the differences in hz?
Inside one of these china girl engines there are alot of inconsitencies/variables to take into consideration, yes?

Would the thickness of even the covers change things?

 

[YetiWoodz]

Yeah idk, I'm getting a lot of outliers too. At full throttle full speed, it flashes 66hz, 180hz, 350hz, and 600hz. So Idk which is the real frequency(s). My front fender slightly taps the front tire which I'm gonna take off, and it makes a high pitched noise so im thinking the 600hz is that but idk.

 

[YetiWoodz]

And im not running a boost bottle yet

 

[HumanPerson]

never mix meatloaf and persimons at the same time