How many CFM carburetor do I need?

How to calculate Carburetor CFM. The formula for calculating how much CFM (cubic feet per minute) your engine requires is: CFM = Cubic Inches x RPM x Volumetric Efficiency ÷ 3456. Any ordinary stock engine will have a volumetric efficiency of about 80%.

How much horsepower can you get from a 396?

The average power numbers from 4,000 to 6,250 rpm (where it carried over 400 lb-ft of torque) were 438 hp and 450 lb-ft of torque. While power peaked at a high 6,400 rpm, low-end torque was still plenty respectable with the motor peaking 483 lb-ft at 4,700 rpm.

Is a 750 carburetor too big for a stock 350?

A 600-cfm carburetor may perform quite well on a stock 350 Chevy. However, the minute you start weaving in power adders like a hotter cam, a dual-plane performance intake manifold, and aluminum heads you’re going to need 700-750 cfm.

Will a bigger carb make my bike faster?

A bigger carburetor alone will not make your bike go faster. In most cases, your bike won’t even start or idle roughly with a carburetor that’s too big. For more power, you should look into a full system performance exhaust and rejetting your carb (not replacing it entirely).

Is a 396 a good motor?

The 396 is a good revving engine, so you’d want to run a steel crank so it would live at the rpm you’d have to run it to make HP. And probably a roller cam, as flat tappet cams in big blocks have a nasty habit of “going away” relatively easily.

What is the difference between a 396 and 402?

Although it displaced 6-cubic-inches more than the 396 and had a bore that was 0.03 inches wider than the 396, Chevrolet marketed the 402 as a 396 on its smaller cars like the Nova, while labeling it as a 402 in its full-size automobiles.

Which carb spacer is best?

The 4-hole plenum spacer is most effective when it’s made from phenolic resin or a polymer. And the good news is that phenolic resin spacers can be stacked, the same way as wood or aluminum spacers. So if insulation and durability are both important to you, this may be the spacer for you.