Jump to content

Hsr42 Float needle for draw through 2.3 vs 4.2 vs 4.5


Recommended Posts

After looking through countless forums for jetting advise for a 1040cc draw through turbo setup im doing. I found a few mentions of the 2.3 float needle being a must. I ordered all sudco had to offer for float needles left to right (2.3,4.2,4.5) and the 2.3 was by far the smallest of the bunch which leaves me scratching my head a bit. Is there some kind of regulating effect the 2.3 gives with a fuel pump that makes it viable? Seems like the most counterintuitive solution and i'd really want to install the 4.5 float seat which has the biggest hole. Keep in mind that the needles themselves are the same between the bunch I checked that already

20210112_204353.jpg

20210112_204334.jpg

Link to comment
12 hours ago, Gixer1460 said:

For a bike carb - even a HSR - 5psi FP isn't low!

1.5 - 2.5psi max is usual pumped pressure!

True 1460. When we were using a s+s super b carb, 2-3 psi. When switching to hsr42, was able to realize 6-7 psi. Just messing around on the dyno with it, that's where the bike liked it best and worked very well at higher rpm's.

Link to comment

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...