Good thread!
Since this thread seems appropriate I'll post my story... .
'94 160hp pump, 370's, Big DV's, stock camplate pushed full forward
, no AFC rack stop... . etc.
I just installed a FP gauge... and am seeing what I think are odd numbers. (I tapped into the P-7100 inlet using an old drilled out overflow valve... . I matched the hole sizes to the OEM inlet banjo bolt - don't want to bottle neck the fuel there... )
Idling in neutral - 20psi
Rev it up to 2krpm and it quickly goes to 25-30psi... then settles down to about 22psi if I hold it there. Same story all the way to 3500rpm.
Highway speeds - 25-30psi steady as a rock. If I poke it at highway speeds and bring it up to darn near double the speed limit it pulls fine... . smooth as can be.
Accelerating from a dead stop (foot to the floor) it pulls hard... . then it acts up immediately (2 seconds after you poke it... ) and starts surging like a son of a gun. The fuel pressure is all over the place when this happens... . but so are the RPM's - since fuel pressure is somewhat dependant on engine RPM this tends to make sense.
If I accelerate slowly it doesn't happen. It happened BIG time @ Muncie when I tried to pull the sled.....
All of this seems centered around the bigger DV's - it never used to do it with the 181's or 131's - because I have never tried to flow as much fuel as I am now.
Lack of AFC?
Sticking and then slipping rack?
Sledpuller Voodoo?
Sucking air?
Need bigger supply line from tank?
Matt
Since this thread seems appropriate I'll post my story... .
'94 160hp pump, 370's, Big DV's, stock camplate pushed full forward

I just installed a FP gauge... and am seeing what I think are odd numbers. (I tapped into the P-7100 inlet using an old drilled out overflow valve... . I matched the hole sizes to the OEM inlet banjo bolt - don't want to bottle neck the fuel there... )
Idling in neutral - 20psi
Rev it up to 2krpm and it quickly goes to 25-30psi... then settles down to about 22psi if I hold it there. Same story all the way to 3500rpm.
Highway speeds - 25-30psi steady as a rock. If I poke it at highway speeds and bring it up to darn near double the speed limit it pulls fine... . smooth as can be.
Accelerating from a dead stop (foot to the floor) it pulls hard... . then it acts up immediately (2 seconds after you poke it... ) and starts surging like a son of a gun. The fuel pressure is all over the place when this happens... . but so are the RPM's - since fuel pressure is somewhat dependant on engine RPM this tends to make sense.
If I accelerate slowly it doesn't happen. It happened BIG time @ Muncie when I tried to pull the sled.....
All of this seems centered around the bigger DV's - it never used to do it with the 181's or 131's - because I have never tried to flow as much fuel as I am now.
Lack of AFC?
Sticking and then slipping rack?
Sledpuller Voodoo?
Sucking air?
Need bigger supply line from tank?
Matt
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