[Tigers] Fuel Pump Pressures

[Jay Laifman]

I also looked through the Archives for this information when I was thinking
of rebuilding the SU or perhaps using the Carter I have.  The Carter is
pretty cool.  It flows the gas without pulses and is very reliable.
However, I never found any clear indication of the PSI rating.  I found one
guy who said he thought it was 3 psi.  I found someone else that said 3-5
is good, and suggested a pressure regulator be used for the common 7 psi
pumps out there.  But, no one came out with any authority of the rating of
the psi.

That said, as someone pointed out, the psi is often affected by the float
valve.  That would be carb specific.  So, for those with non-stock carbs,
they need to look to the specs of their carbs.

I do know that Weber specifically provides that the Webers for Porsches
should be at 2.5-3.5 psi.  But, those float valves are much different than
I have been used to in other cars.  They vary their rate of flow based upon
the level of the float.  They are not just on/off valves that close at the
top.  So, on those, it is critical to have the right psi/flow and to set
the floats at the top and the bottom (I'm used to just the top).

Jay