New Guy - '65 273 Valiant Convertible

punkybub said

Two7T3Dart - since there's no commentary in the parts section (from what I read) I'd like to ask you here: is it the 4bbl carb that makes the difference between a regular Valiant (Signet in this case) and a Commando?

This car had a 2bbl originally and during this rebuild I had the 4bbl manifold/carb put on with pretty much stock cam I think (?). I just wanted the power when I needed it and the economy when I didn't need power.

So much to learn - thanks for any info.

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Basically, the differences between a regular 273 (2bbl) and a 273 Commando (Plymouth's name) and a 273 Charger (Dodge's name) are: Hi-comp pistons (10.5:1), a bit hotter camshaft, the iron 4bbl intake with Carter 500cfm AFB 4bbl carb, dual-point distributor, fancy valve covers, and chrome air cleaner.

Even using the iron 4bbl intake and AFB carb will be a vast improvement over the 2bbl setup. You can run the 2bbl cam as well...actually preferable given the "cat-piss" they call gasoline these days. Being a small displacement engine, it's real easy to over-cam or over-carb these things.