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Pro Action Vortex Carb Mod
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Posted by: ryder---------------------
Just wanted to pass on some good info. I recently had my carb modified by Pro Action. Basically, they cut grooves into the cylinder side of the carb throat (much the same as rifling in a gun barrel). As the grooves get closer to the cylinder, they get closer together. This creates a swirling effect in the air/fuel mixture and actually "packs" the mixture to achieve more volume in the charge. Don't quote me on this, but I believe the company claims an increase in horspower of around 3/4 of a pony.
Anyway, I just rode the bike with the "new and improved" carb for the first time this weekend and it rocks. I found the motor picks up off idle better and makes more power across the entire rpm range. Throttle response is absolutely wicked and I can run corners a gear higher.
Guys, I don't see a down side to this and would highly recommend this mod. Anybody else tried this yet?
Posted by: '00kx250spode---------------------
I thought there was a thread on this a while ago - and the verdict was that it was bull. I think Rich didn't think too highly of it - if I remember right. Rich correct me if I'm putting words in your mouth.
I'm not disputing your results. Just stating what I remember reading. I would like to hear others experience with this mod - since I've run out of mods to try on my KX310. 
Posted by: ryder---------------------
Yeah, there was a thread about it. I just read it. I'm sure those guys know a lot more about the subject than I do, so maybe the results are just in my head--I dunno. I recall someone said the principle "went against the laws of fluid dynamics", but I still don't understand why it wouldn't work. Could someone explain it in more detail? If rifle barreling can spin a bullet, why wouldn't this spin the fuel mixture?
Posted by: Rich Rohrich---------------------
Quote:
Originally posted by ryder
If rifle barreling can spin a bullet, why wouldn't this spin the fuel mixture?
|
For starters think about the following and I think you'll be able to answer your own question:
- the mass difference between a bullet and a column of air
- the velocity difference between a bullet traveling through a barrel and the constantly variable velocity of a column of air
- the compressibility of air and the relative compressibility of a bullet
- the center of a bullet is travelling at the same speed as the outer surface of the bullet. The center of a column of air in a pipe or port is travelling at a higher rate of speed than the air next to the port surface which is at a virtual stand still (boundary layer)
- creating additional turbulence (i.e spinning the air as PA claims) would only serve to reduce the mass airflow at the exit of the carb. (FYI I have tested this on a flow bench, which I'll venture a guess PA has not).
- airflow is probably the least intuitive thing on the face of the earth. In other words air rarely does what most people assume regardless of how much money you spend marketing a concept.
I'm glad you are happy with the mod. Any time you spend money and walk away pleased it's a good day, but I put this out as a warning to perspective buyers of ANY too good to be true technology.
Ask specific questions of the person taking your money and DEMAND documented proof (test data) if you aren't sure about a questionable technology or product .
Highly accurate air flow test equipment is very affordable and reasonably simple to operate. There is really no excuse for a big company selling carb related mods to not have test data available. Don't buy into the "but our test riders loved it" nonsense.
As for me, when a suspension guy who took business classes in college and has never touched a flow bench (unless his set his coffee down on someone else's bench while visiting a competitor) tries to sell me an "advanced fluid dynamic concept" with no hard data, I tend to hide my wallet just like I do in the subway. :D
Caveat Emptor
Posted by: steve125---------------------
ryder along with the carb mod from Pro action was your jetting altered in any way? If so, then most likely that could be where your real gain in power came from. I'm quite sure that proper jetting will out perform those grooves in the carb bore by a large margin.
Posted by: ryder---------------------
Thanks for setting me straight Rich. Everything you said makes sense. I never considered that the characteristics of a gas would be different than that of a solid. Steve, jetting was altered so I'm sure you're right. I guess I need to learn more about jetting. Any recommendations? Thanks again to both of you.
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