Im also looking for a Holley 4bbl to go on my 318, wanting the extra pwer from the 4bbl.

 

318 -

It "might" with the right CFM, but without the right cam and exhaust, the benefits, while real, won't be as great as they could be.

Yes, the tranny's stall converter and rear gears matter too!

Still, for most new hot-rodders, the carb/manifold swap is the first step.

I'd have that tranny /kick-down checked out first though.

Archer

 

When I switched from 2bbl to 4bbl on my 318, I didn’t notice much power gain, honestly. It idled and ran better, for sure, because the carb was brand new, but it sure didn’t thump any harder.

In fact, the biggest “seat of the pants” upgrade I did was replacing the factory fan with an electric unit. Man, that’s a difference!

 

When you say you put in an electric fan, do you mean the cooling fan on the radiator? I never thought of this as something that would boost power. How would I go about doing that myself? Currently have a belt-driven fan.

 

RS -

An electric fan doesn't make power, is "saves" power. The HP needed to spin the fan can now go into spinning the wheels.
However, an electric fan will require more output from your alternator (which also uses up more HP) and your wiring has to be up to snuff, if you decide to get a "bigger" alternator.

If you have a clutch fan on there (that works), you might be hard pressed to do that much better.

Archer

 

David Friberger did a episode on Engine Masters, electric and mechanical, he also did a hp loss for running an altters ernator for an electric fan. He came up with the electric fan and alternator took less hp to run than a mechanical fan.