Cleveland Question?

That is how you tell the difference...that and the larger port sizes on a 4v.

Here's a page with some casting numbers:

It's been my understanding that 2v heads have more low-end and the 4v heads make their power high in the RPM range.

Agree, the 4bbl heads are too big for the street, typically. Check your references - the '73 Q code very well could have the 2bbl heads, which are huge to begin with, leading into the "smog" motor era...

Rob

FYI: Cleveland 4V heads feature larger ports/valves than the Cleveland 2V heads. The 70-71 Cleveland 4V heads also feature a closed or quench-type combustion chamber - 2V heads feature an open combustion chamber. 2V heads also feature non-adjustable rocker arms.

Cleveland 4V intake diameter 2.19", exhaust diameter 1.71" Cleveland 2V intake diameter 2.04", exhaust diameter 1.65"

On Fri, 12 Nov 2004 14:50:23 -0500, Dean rearranged some electrons to form:

According to Ganahl's book, 351Cs in 73 had open chamber (2V) heads. However they may have varied, the 4V heads have open chambers with the (larger) 4V valves and port sizes.

David Said(incase you missed it):

According to Ganahl's book, 351Cs in 73 had open chamber (2V) heads. However they may have varied, the 4V heads have open chambers with the (larger) 4V valves and port sizes.

-- David M (dmacchiarolo)

Rob

Just a suggestion: I'm currently building a 351C for my '72 mach 1 and I've decided to go with the "Aussie" heads. They're the best of both worlds, the fuel economy and low-end torque of the

Good luck!

-Dave

BullShit!!!

The only people who make this totally absurd statement are those who have NEVER DRIVEN a 351 Cleveland with 4 barrel heads! If you ever get to drive one you will see how silly your statement really is...

No!

The 4 barrel Cleveland engines all came with 4 barrel heads from the factory. The 4 barrel heads have larger ports as well as valves, and the came in either open chamber or closed (quench) chamber styles. I have some of both types. All 4 barrel heads have the digit 4 cast on the top corners just outside the valve covers. While All 2 barrel heads have the digit 2 cast on the top corners just outside the valve covers.

You CAN NOT determine weather the block is a four bolt main by the casting number. You have to pull the oil pan and visually look at the main caps to tell. My 1971 four bolt main, open chamber 4 barrel heads, Cobra Jet engines casting numbers do not indicate that is what it is, according to any reference sources.

My guess is someone swapped the 4 barrel heads for 2 barrel heads, or you have a complete two barrel engine that someone stuck a four barrel intake on it.

By The Way: Don't get caught up in this CRAP about the 4 barrel heads not producing torque. There is no lack of torque in a 4 barrel Cleveland. Anyone who has had the pleasure of driving one knows this. :-)