Two cylinders, one heart… or carburetor

[Halftwist]

I’d like to change over to a single carb set up on my bobber. The intake isn’t an issue I’ve got that built for the most part. I was wondering what carb works well for the job and what jets to use.
Set up is as follows:
2 1/2” intake pipe length .
3 1/4’ header pipes with light insert baffles.
usual operating altitude 3500ft above sea level.

What do the wise ones say?

 

[BluzPlayer]

Hello Halftwist.
I can't really help you out with any precise information. I do have a 2 into 1 for my project. It came with a vm36 carb. Reported to have ran fine and I was told it's ready for plug and play but I am sure it will need sorting out once I get to that stage.
It will be interesting to see what direction you go and how well it performs. Good luck

 

[gggGary]

Since the cylinders pull charge alternately,a single will be set up VERY similar to jetting used on a two carb set up. VM34's can be had jetted close to what the Ole 6fitty motor needs.
This may be some worthwhile reading hint Teecat did a lot of writing about his single carb conversion trials and tribulations.

 

[Halftwist]

Since the cylinders pull charge alternately,a single will be set up VERY similar to jetting used on a two carb set up. VM34's can be had jetted close to what the Ole 6fitty motor needs.

I didn’t even consider that it’s still only one cylinder asking for fuel at a time so yea that makes sense. For some reason I thought I’d have to go big. Would you go with a vacuum carb?

 

[gggGary]

3500 you will prolly go a bit leaner then normal.
Don't go vacuum unless you will run a roomy air filter on it.

 

[Halftwist]

It will lean out at midrange? Is there a way to tune around that or would you say it’s inevitable. What if I went to a 36. I’m sorry I grew up in the time of fuel injection and electric cars so I’m fairly carb illiterate.

I was just going to run a uni pod like I run on my bs 38s. How do run a vm not on vacuum? I see teecat mentioned it but I can’t find where he explains that

 

[gggGary]

Might be less of an issue with the single carb, (faster pulses so less variation) but the slide tends to pulsate at mid RPM's with a small volume airfilter.
(that's my story and I'm sticking to it)