OEM Carb Mods While You Are Saving For FCR Flatslides.

[ducpainter]

I think I'd have done the same knowing what little I do about the subject.

The laminar flow thing on the downstream side is what really gets tricky.

[koko64]

Yeah, I know a bloke in the 80's who polished the ports of his race motor only later having to tear it down to scuff up the heads.
I hadnt my licence long and this guy was a racer who started explaining this stuff to me. He found out the hard way. It was like another language, I was pretty green and just learning  about, well, everything!

[ducatiz]

I wonder if there would be any advantage with a vortex shaped surface leading into the bell mouth?  Something to direct the incoming air in a pattern..

[koko64]

I really dunno. Modifying evidence of cost cutting is easier. What do you mean?

You got a pic of unmolested carbs?

[koko64]

Actually...my stock carbs were gifted to another member that had a set on his SS that were acting up.

I'll never have to look at the inside of them again.

Nibor has a set of stockers. I'll ask him to take a pic to show the hard edges on the slide and in the throat.

[Nibor]

I'll pass it on to Nibor and let you know when he gets back to me!

[koko64]

When he tells you, let me know

[koko64]

PM sent.

[koko64]

Nibor came by last night with a set of stock carbs off Nugget and took some pics.

Examining the stockers, not only does the bellmouth to throat area transition have an angle from the front of the carb, but drops over into a lip or ridge because the carb is bored from the rear and the boring stops short of the bellmouth casting. You cant see it, but its quite pronounced when feeling it with your finger. That wouldnt help smooth airflow. I'm guessing that if the bore went through, they would have had to clean up the angle by hand, which costs. Like I said, built down to a price. You dont see that on Keihin or Mikuni performance carbs.

When cleaning up that area don't venture too deep and damage the bore and CV slide recess. Stay short of that area unless you are Jerry Branch. Im only suggesting the mods that shops have been doing since carbs were invented but are DIY. Just want to clean things up a bit and get a nice radius on transitions.

Thanks for your help Nibor.

[koko64]

You can see how unfinished the stock carbs are to meet the price point.
The modified carbs aren't quite finished, but you get the idea.

[koko64]

I wonder if there would be any advantage with a vortex shaped surface leading into the bell mouth?  Something to direct the incoming air in a pattern..

I Googled Vortex to get the Fluid Dynamics perspective rather than the Star Trek perspective.

[MotoPsycho]

You guys are spelling it wrong.

http://www.vorteccyclone.com/what-is-it.html

[ducatiz]

You guys are spelling it wrong.

http://www.vorteccyclone.com/what-is-it.html

that's interesting.

my thought was that it would enable a better mixture and "aim" the air flow.. no idea something like that existed.

[Dirty Duc]

Vortex generator testing:
http://www.popularmechanics.com/cars/a310/1802932/

[ducatiz]

Vortex generator testing:
http://www.popularmechanics.com/cars/a310/1802932/

That is not what I had in mind -- that adds an obstruction to the air intake.

I'm saying to shape the intake bell mouth sids in such a way as to have a vortex shape -- not add vanes to the center.