351c ?

[snowb07]

I was wondering if there is anyway to tell by just looking at the outside of a 351c if it is a 2v or 4v. with out taking it apart.
Thanks

 

[Gud T.B. Blown]

4V heads have the number "4" cast onto the top corners of the head.

 

[D.Hearne]

The "2" or "4" is next to the valve cover in the corner.

 

[snowb07]

thank you

 

[HHStang]

I thought you could tell by the air filter cover...

 

[D.Hearne]

I thought you could tell by the air filter cover...

Well you CAN tell by the air cleaner cover whether or not the cover is a "2V" or "4V" item or not, but alot can happen to the engine under it in 30-something years. Or in simpler terms, what's on the cover, doesn't guarantee that what's under it is what's on that sticker. Both engines used the same aircleaner assembly in many cases. 2V means it's a 2 Venturi carburetor or barrel, 4V means it's a 4 Venturi carb. The Venturi is the section of the throttle bore that necks down to increase the air velocity and increase that signal to the Booster Venturi to pull the fuel from the bowls. The Booster is the round thing hanging out over the throttle bore.

 

[bigcat]

need a pic of the 4? (or 2). i can run down and snap a quick photo....

 

[snowb07]

that would be great, as the engine is covered with dirt and grim..

 

[bigcat]

look on the left hand side of the head, in the top corner.....

 

[HHStang]

sorry man- I was kidding...

Well you CAN tell by the air cleaner cover whether or not the cover is a "2V" or "4V" item or not, but alot can happen to the engine under it in 30-something years. Or in simpler terms, what's on the cover, doesn't guarantee that what's under it is what's on that sticker. Both engines used the same aircleaner assembly in many cases. 2V means it's a 2 Venturi carburetor or barrel, 4V means it's a 4 Venturi carb. The Venturi is the section of the throttle bore that necks down to increase the air velocity and increase that signal to the Booster Venturi to pull the fuel from the bowls. The Booster is the round thing hanging out over the throttle bore.Well you CAN tell by the air cleaner cover whether or not the cover is a "2V" or "4V" item or not, but alot can happen to the engine under it in 30-something years. Or in simpler terms, what's on the cover, doesn't guarantee that what's under it is what's on that sticker. Both engines used the same aircleaner assembly in many cases. 2V means it's a 2 Venturi carburetor or barrel, 4V means it's a 4 Venturi carb. The Venturi is the section of the throttle bore that necks down to increase the air velocity and increase that signal to the Booster Venturi to pull the fuel from the bowls. The Booster is the round thing hanging out over the throttle boreWell you CAN tell by the air cleaner cover whether or not the cover is a "2V" or "4V" item or not, but alot can happen to the engine under it in 30-something years. Or in simpler terms, what's on the cover, doesn't guarantee that what's under it is what's on that sticker. Both engines used the same aircleaner assembly in many cases. 2V means it's a 2 Venturi carburetor or barrel, 4V means it's a 4 Venturi carb. The Venturi is the section of the throttle bore that necks down to increase the air velocity and increase that signal to the Booster Venturi to pull the fuel from the bowls. The Booster is the round thing hanging out over the throttle bore

 

[D.Hearne]

I really had that post aimed at snowb07, he seemed lost. And I figured he was maybe a young'n that had never seen a carb before.

 

[CochinoFilipino]

,,, 2V means it's a 2 Venturi carburetor or barrel, 4V means it's a 4 Venturi carb. ,,,

Awesome! I finally know what the "V" stands for.

 

[snowb07]

thank you fpr the pics and the explaination...
with that in mind is there a big performance difference between the two

 

[bigcat]

the 4V heads are better for high RPM, while the 2V are better for the street. people will tell you that 4V is fine for the street, but it is a little soggy in the lower RPMs. IMO my 2V motor will run circles around my 4V on the street. racing, thats another story.....

 

[D.Hearne]

The 4 bbl heads are only soggy if you choose the wrong cam, intake and carb. Stick with a 600-700 cfm carb, vacuum secondaries, a dual plane intake and not too much cam and they're fine.

 

[Hack]

From the dyno numbers I've seen, 4V must only seem soggy in the bottom end due to the incredible top end. It's just so much stronger in the top that the bottom doesn't seem as good. In reality there's very little difference in the bottom between 2V and 4V and I've seen some 4V builds that had a better bottom as well as the top.

But hey, buy some 2V Aussie 302C heads if you want. The more Clevelands running here in the US the better IMO.

 

[ddonaca351]

If ya need Aussie stuff, there is a place right across the river in Portland, Oregon (from me, that is).
www.ausfordparts.com *IF* I remember right, but its something pretty close to that, google should hook ya up.
He sells on E-bay too.

Good luck,
Dave-