Faster Plane

In my ’71 Duster I currently run a
1970 stock compression 340 with ported
J-heads, a Comp. XE284H cam, an Edelbrock
Airgap intake, Ed 800 CFM carb,
3500 stall TCI, and 3.91:1 gears. I only
street drive it but usually pretty hard,
always redline. Would a single-plane and/
or double-pumper carb add much power or
just change the power band? I also oversize
fuel lines, sender, and pump to install. (P.S.
I just ordered an MSD to replace the MP
distributor I bought in 2001.) Also, I love the
photos of your cars at Derham’s alignment
shop [Newburgh, NY – ed.] I have known
them for years.

A big single-plane will definitely pick
you up some power and would be an
excellent match for your converter and
gears, eventually you might want a bit
more cam duration, too. The DP carb,
though, might improve the launch a tad
but would do nothing for power and really
trash fuel economy and fuel wash (trashing
the rings). Double-pumpers are suitable
for drag-only cars only. Remember, if
the car sees any street time, your distributor
must have vacuum advance.
Poughquag! I spent many happy afternoons
at Poughquag Auto Wreckers in
the ’70s. I remember the owner, Charlie
(?) was a real pistol, his kids wandered
barefoot and nearly naked amongst the
wrecks, mud, and parts. His driver was
a ’69 Road Runner. One day his ’Runner
was suddenly out with the wrecks. Seems
his wife had broken all the glass out of it.
Every single pane was gone. He must’ve
pushed one of her hot buttons.