How much CFM do Vortec heads flow?

Unported, with all the other tricks in place, the Vortec’s will flow about 235-240 CFM at 0.500” intake and 165-170 cfm at 0.500” exhaust, on a 4″ bore at 28″ H2O, with clay radiused port opening. With some careful porting there is another 5-10 CFM or so to be had.

Will Vortec heads fit on a 327?

The L31 Vortec heads will bolt onto any Gen I small block. Your 327 isn’t any different than any other Gen I small block built from 1955 thru 2002. The main difference with using the Vortec heads is the different intake bolt pattern as already mentioned.

Can you use vortec heads on a 350?

With a 8 bolt vortec intake, sure you can. Yes the 1996-02 L31 350 vortec heads will bolt to ANY gen 1 350 engine. I just did this conversion last winter. Block was a 1969 350 4 bolt main. May as well do the cam also. You’re more than half way there when you do the top end swap. The vortec’s with the XE268H cam really woke up the engine.

When did the Vortec cylinder heads come out?

Vortec heads were designed based on the 1996 Caprice 9C1/Impala SS LT1 cast-iron head castings. The only difference is the water jacket revision so these heads could be used on conventionally-cooled small blocks.

What’s the lift clearance on a Vortec iron head?

The stock Vortec iron head will not tolerate more than 0.440-inch lift. We measured our stock iron heads right out of the box and the retainer-to-seal clearance was only 0.470-inch. Subtract the standard 0.050-inch clearance, this leaves only enough room for a 0.420-inch lift cam.

How much horsepower does a Vortec bow tie head have?

The Vortec Heads come with various intake and exhaust valve sizes to complement the high-velocity port design and your performance needs. Vortec Heads outflow Bow Tie Heads right out of the box and are a 20 to 40 horsepower bolt-on increase over earlier cast iron small block heads.

Which is the weak part of the Vortec cylinder head?

The exhaust port, considered to be the “weak” part of the otherwise steller-flowing Vortec head, actually does not flow that bad but because the intake port is so good, responds better to port work than does the intake and there is a strong feeling in some camps that these heads make best power with a split-duration camshaft because of this aspect.

What kind of cylinder heads do Chevy performance use?

Chevrolet Performance Small Block Chevy Cast Iron Vortec Cylinder Heads. America’s favorite high-performance cast iron small block cylinder heads offer big power and bigger value. Chevrolet Vortec Cylinder Heads’ fast burn combustion chamber and high-velocity ports combine to produce big horsepower.