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What fuel pressure?

  • Thread starter Thread starter NKau
  • Start date Start date Sep 5, 2008

NKau

Founding Member
Dec 15, 2001
1,346
0
37
Jefferson, WI
Sep 5, 2008
#1
  • Sep 5, 2008
  • #1
Mods are in sig below. I was running between 39-40 psi when I last checked (not changed when we installed the new engine), and was only able to trap as high as 103.7 mph when I got it to the track last fall. Wanted to see what I could squeeze out of it before getting a 'real tune'.
 

Vipersix

Founding Member
Feb 25, 2001
434
0
0
Clarksville, TN
Sep 6, 2008
#2
  • Sep 6, 2008
  • #2
You should probably check to see what pressure the manufacturer tests its injectors at. Most use 43.5 psi. This directly affects your flow numbers and can starve (or drown) an engine depending on what you believe you're pumping versus what you are actually pumping. For example, if your injectors were rated at 43.5 psi your actual flow at 40 psi is only 23 lbs/hr.

New Flow Rate = [SqRt (New psi/Old psi)] * Old Flow Rate
 
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