It’s all relative. These early chevy motors respond to being hot rodded just like any other motor. More carb, more cam, more compression, more spark, more gear, more rpm, it all adds up to more power. But it’s all relative. These are relatively small motors so the gains are relatively small. You just can’t bolt an offy 2x1 on a 235 and turn it into a screaming high hp power V8 killer, lol. For those of us who like to mess with our inline motors we measure success more modestly.
My first modification, I bolted a Weiand 2X1 on a 235 in 82. The car it was in ran a little faster with the two carbs than the one carb. It was not a lot faster, but a little faster. Then it was a rebuild on the motor, then a cam, Clifford headers, head work.
Never very fast but it was fun tinkering with it all.
Put your offy on and go have fun. Add a little water heat to the bottom of the intake (the fentons have provision for copper tubes to get exhaust heat but I have never found those tubes to work all that well.)
Alternatives to the single bbl. Rochester carb, 1974 Ford Pinto Holley Weber 5200 progressive 2bbls. Small primaries, larger secondaries, almost perfect for a 2x2 install. The Rochesters can be a little too big and tend to run fat. Smaller carter w-1 carbs would be a choice.
But if you want to use the Rochesters, and get them right, here is a link to Pat Smith’s excellent article on how to do it. Pat was Dyson Racing’s IMSA crew chief for many years and one of the best minds I knew when it came to this stuff.
https://www.inliners.org/tech/tech4.htmlBigger 261s with all the mods can handle bigger carbs. One of my 261s uses a pair of Holley 2300 350 cfm carbs and runs great.
But it’s relative. Small motor small gains.
Go have fun my friend.
