Thermoquad choke question
This type of choke well should be what you have-
On this type, the choke well is open to the exhaust crossover. As such, it needs a "bathtub" which sits in the well, and a gasket to go between them, like this:
This seals the crossover and prevents exhaust leaks.
You can most likely use the one from your 318 manifold, or else some kits have them included.
72 340 THERMOQUAD CHOKE STAT, AND CUP. | eBay
Then the choke thermostat gets installed on top of the tub.
Bucks down? Use your 318 BBD choke. Bolt it up to the 340 manifold, and set the TQ and it's spacer gasket (you absolutely need the thick isolator gasket, just like the factory used) on the manifold, and make sure the carb's choke is closed. Now attempt to line up the thermostat's choke rod with the choke arm on the carburetor- you'll probably find the rod is about two inches too short. Now get creative- look at the coil spring, and you'll see that it can be separated from the rod fairly easily with a little finagling. Now get a piece of rod, coat hanger, whatever- and start bending. Mimic the ends of the old rod, adjust the length measurement to fit making sure it will not interfere with any carb linkages or fittings. Reinstall your new rod on the spring, and hook up to the carb, making sure it has free range of motion.
It will now operate as intended- the thermostatic coil doesn't care if it is operating a 2 or 4 barrel, only the rod differs.
This type of choke well should be what you have-
On this type, the choke well is open to the exhaust crossover. As such, it needs a "bathtub" which sits in the well, and a gasket to go between them, like this:
This seals the crossover and prevents exhaust leaks.
You can most likely use the one from your 318 manifold, or else some kits have them included.
72 340 THERMOQUAD CHOKE STAT, AND CUP. | eBay
Then the choke thermostat gets installed on top of the tub.
Bucks down? Use your 318 BBD choke. Bolt it up to the 340 manifold, and set the TQ and it's spacer gasket (you absolutely need the thick isolator gasket, just like the factory used) on the manifold, and make sure the carb's choke is closed. Now attempt to line up the thermostat's choke rod with the choke arm on the carburetor- you'll probably find the rod is about two inches too short. Now get creative- look at the coil spring, and you'll see that it can be separated from the rod fairly easily with a little finagling. Now get a piece of rod, coat hanger, whatever- and start bending. Mimic the ends of the old rod, adjust the length measurement to fit making sure it will not interfere with any carb linkages or fittings. Reinstall your new rod on the spring, and hook up to the carb, making sure it has free range of motion.
It will now operate as intended- the thermostatic coil doesn't care if it is operating a 2 or 4 barrel, only the rod differs.
