Intake Boot Length

[Mick Milakovic]

Hi All,

I'm converting my Harescrambler from the worn-out Bing to a Mikuni.  I've made the first cut on my carb-to-intake boot, and I know it's too long, but I was wondering if the length of the boot can affect power, and if so, in what way?

Thanks, in advance, because I know someone out there knows the answer to this question!

Mick

[firstturn]

Mick,
  Here is the theory I have operated under many years. To answer your question of the length you should be OK since you are not going after specific "all out High or Low range racing".  I use velocity stacks in some of my specific applications since I feel that gas "floats" around between 2 to 6 inches past the slide when the piston (or in 4 Cycle valve) closes.  Just for  some other information in "Theory" Velocity stacks are a Convergent Duct, meaning the air will increase in veleocity as it goes through the stack which is what I want.
  I hope Nelson makes a comment.


Ron Carbaugh

[linglewn]

Ron,
No additional comment needed. I agree with your explanation.

Nelson Lingle
73 Jackpiner
74 Jackpiner
71 DKW 125

[firstturn]

Thanks Nelson...you are the man with all the formulas and I respect that.

Ron Carbaugh

[Mick Milakovic]

Ron and Nelson, thanks, appreciate the feedback.

Mick

[Paul Danik]

Hi Mick,

   The old school guys that I hung with who did those types of conversions usually agreed that a little longer inlet tube would help with ease of starting and good bottom end response. If they were after high end performance and were willing to give up a little at the bottom they shortened the tube.

    Hope that helps, and hope to see you at VMD.

Paul

[Mick Milakovic]

Thanks Paul, I'm into easy starting!

Mick