This device looks very interesting, and I’m curious about how it works and affects engine performance. I hope someone comes along and explains things better than I can. But for now I’ll just throw some things out there. From their animations, it is visually shown that they are accelerating airflow through the carburetor by somehow fixing a flat plate about halfway in the mouth of the carb. In the two top animations, they show turbulence in the back of the carburetor slide at ¼ to ½ opening. I am pretty sure that there would be a swirl effect here, but without doing some experimenting and probing here, we can’t know how serious it is. There are also probably a lot of variables here, including carburetor bore diameter, and engine speed at each throttle opening that would affect that turbulence. It seems that that is their main argument for their product; reduced turbulence behind the carburetor slide and resulting acceleration of air.
At ¼ throttle opening, they still have some turbulence going on too. On one of the other pages, they also advertise another plate on the opposite side of the slide that would decrease the swirl effect on that side. I’m curious about this; I’d like to see some CFM numbers here to back up what they’re saying.
I always find that a company that shoves dyno numbers in your face is just looking for attention. I think it’s especially interesting in this case that they’re advertising ¼ throttle, but their charts are showing a full run. And I’m having a hard time seeing the difference between their charts. Going by the charts, clearly there are other modifications to the engine to be able to top out with more horsepower. Their device is only supposed to affect midrange response, and I don’t understand how it can yield better overall power. And there’s no way a two-stroke will rev out to 9500 RPMs on ¼ throttle. It would make a lot more sense if they showed us CFM numbers through carburetors with and without their product, rather than using dyno charts they seemingly pulled from somewhere else.
One of the claims is “volumetric engine efficiency through uncompromised airflow velocity.” On our two-stroke Blaster engines, volumetric efficiency is much more affected by cylinder porting and scavenging; widths, heights, angles, and directions of transfer ports into the cylinder, exhaust port shape and time/area, not to mention crankcase pumping and the incredible effect of the tuned exhaust. With this carburetor mod, we may be smoothing out our airflow into the cylinder, but if our cylinders have stock porting (nasty bumps and dips that come from the aluminum casting process) we certainly will be restricting that air movement inside the barrel. Like blasterfreak said, milling the head can be an inexpensive performance gain since the Blaster has a squish height that is much too thick to do us any good; mixture trapped there is useless because it never gets burned. When we lower the squish height, we’re putting more of the compressed mixture in the burn path by cutting off its escape route.
Something else I thought I’d mention while we’re on the subject is that sometimes magazines are bribed to give good review to products. The magazines are sent products to review, sometimes with other incentives, and they give a good review so they get to keep the product and whatever else they’re given. It’s all about money.
Don’t get me wrong, this is certainly an interesting mod, and it may indeed help on some tracks when coming out of corners. But I wonder if someone hasn’t thought of it before and found some problem with it. I wonder if this is leaning out the midrange without a needle adjustment. A thinner needle may have to be installed to allow more fuel to be drawn up from the bowl to be mixed with more air at part-throttle openings.
I would be very interested if someone else has any experience with this, and I hope someone with more knowledge about it comes along and clears things up here. But I guess for now, I’d rather spend money on quality porting to get more mixture where it really needs to be, inside the cylinder.
