|
by Dave Koehler
12/8/04
 |
Hi Dave!
This is likely one that you
get a sore neck from shaking your head but here
goes. My son and I found and pieced back together
a 1969 FED played with carbed gas and then switched
to injected methanol mid-season. We are now building
a blown injected small block for next year. Now
for the dumb question,would it not make sense
to run a belt drive pump driven by the top blower
pulley? -- i.e. the fuel would be referenced off
the air pump, more air more fuel. I know of no
one that is doing this-- yet there are plenty
that think straddling an 8 3/4 Chrysler is crazy...
any thoughts?
About the pump, we are staying
with the FED.
Thanks,
Dave Ahlstrand
Round Barn Racing
BACK IN BLACK
Front Engine Dragster
Davey Ne.
|
|
 |
Dave,
I am known for some rather bizarre concepts but never considered
this one. This idea may fall under the heading of something
my late farmer father used to growl at me. "Do not reinvent
the wheel before learning how to make it roll downhill first."
The proper fuel pump for your application is chosen to provide
more than the amount of fuel required to feed the blown monster
and is designed to be run at 50% underdrive (cam speed) or
close to it. If you ran it off the top pulley at 20% blower
overdrive you are now driving the pump 120% over the original
pump design speed. Driving your original pump off of the top
pulley would result in some rather serious tuning problems
and the pump would probably reach a saturation/cavitation
point somewhere around 4500 engine rpm. This could be a very
short race. Driving the proper pump at cam speed would achieve
the same thing as going off the top pulley with a little bitty
pump to match the needed fuel curve.
If you go this route with the original pump you will be required
by the Sorely Underpaid
Crew Chiefs Society
to supply Stickers For
Income umbrellas for anyone standing in the vicinity
of the car.
Despite the feeble humor, never quit thinking and scheming.
FEDs forever!
Have a safe race,
Dave Koehler
 |
Fuel
for Thought [11/9/04]
Dave Koehler answers your nitrous & fuel-injection related questions |
|
 |
|
