'72-'75 G180 mods: I've got a '75 Luv with non-crossflow head. First got a Weber 32DFTA-10A off a '78-'83 Ford Fiesta, so it's a Motorcraft model 740. I used the old Tomco rebuild kit # 5490B gotten off e-bay. Had a heck of a time getting a manifold adapter that would work, finally had to mix/match. Used the old style TransDapt adapter, but that's like a big rectangular funnel, no port dividers. Had to fab an aluminum plate to fit on top, Weber on top of that. Fabbed my own cable linkage. Ran stronger but far from great so time to re-think.
Re-did it all. Ported the stock round intake manifold runners to better match square head ports. Ported and opened up carb mount plenum section to match Weber throats, opened and smoothed interior contours. Modified Weber mounting holes to fit LUV intake, just barely enough meat there, but had to reinforce with hi-strength epoxy in carb base. Removed choke and electronic/SMOG parts from carb, removed choke blades, linkage & shafts.
All that foolishness to maintain stock dual port, one- port-per carb throat intake. Takes advantage of stock 'dual plane' manifold plenum design for better bottom end & torque, yet allow free breathing and more power on top end. This way no aftermarket adapters needed.
Eliminated every part of SMOG stuff. Removed 4-port EGR manifold and jet tubes from head, plugged holes in head using the jet tube flare nuts with a bolt brazed in place of tube. Removed air pump and all related SMOG, changed from solenoid controlled vacuum to straight manifold vacuum for distributor. Left vacuum solenoid in place to vent crankcase etc. Only using a PCV valve, all that's required on '75 and older vehicles in Kalifornia.
Welded up a different throttle lever, and fabbed a new throttle cable 'L' mounting bracket. Gotta be careful on throtte linkage on throttle shaft, if not re-assembled correctly the spring can jam it up. Also be careful because under some carb components removed [throttle kicker assy, electric choke assy] there's a bleed or vacuum orifice hole, sometimes needs to be sealed with a screw.
Idle shutoff solenoid must be wired to ignition hot, bowl vent solenoid doesn't need electrical connection. This carb uses a fuel supply and a return line like stock LUV. There's a brass welch plug with plastic plug underneath covering up the idle mixture needle, drill out and pry out carefully so you can adjust.
Ported the stock phenolic carb insulator to match Weber throats. Got it all hooked up and ran terrible, everything wrong. Fiddled and got it at least driveable, but lousy idle, miss, and carb hissing real loud.
Took a piece of plastic fuel line and used as stethoscope to trace down source of hiss. Turns out Weber DFTA carb base has some bleed ports that were not sealed by stock LUV phenolic spacer & gasket, not wide enough. Pulled carb and fabbed up an aluminum plate, about 3/16" thick, to match Weber base width and cut gaskets, to place on top of stock phenolic insulator and under Weber.
SUCCESS! Idles great, miss gone, no flat spot, quick acceleration. Now expecting much better bottom end, better mid-range and strong top end with much better mileage to boot. Got a fuel pressure regulator but haven't installed yet. Pain in the but to adapt this carb, pretty tricky, but requires no aftermarket adapters, just a bunch of hand tools, time and congential insanity.
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