Welcome! The first tip is to decide what exactly you want the car to do differently than it does now, and figure out how much money and time you've got for the project. Remember also that when the car can go faster and quicker, it needs to
steer and
stop faster and quicker, too.
Before you do any modifications, you'll want to give the car a top-notch tune-up. Tune-up parts and technique suggestions in
this thread. Remember this engine has solid lifters and needs periodic
valve adjustment. You will also pick up a great deal of driveability with two simple underhood tweaks: set the base timing to 5° BTDC rather than the factory spec of 0°, and bypass the OSAC valve. The latter is a widget on the passenger side of the firewall with two vacuum hoses running to it: one from the carburetor and the other to the distributor. What you want to do is run
one hose directly from carburetor to distributor, leaving the OSAC valve out of it.
Once you set out to do modifications and upgrades, you'll hear the name "Clifford" come up, but be very careful before you decide to spend any money with Clifford. They have a long and ugly reputation for being a bunch of clowns; see for example
here,
here,
here,
here, and
here. Much of what they sell is inaccurately described, and a lot of it is not even slightly cost-effective. The good news is that you don't need to go to Clifford to get hot rod parts for slant-6s; there are lots of other, better options. See for example
Dutra Duals and header options discussed in
this thread and
this one,
Erson custom cams,
HEI ignition upgrade,
Mike Jeffreys windage trays,
Hurricane intakes,
other exotic intakes. Hi-perf engine buildup
here, high-perf parts and build info
here.
