Do all 350 Vortec heads have the "sawtooth" marks?

[clampjockey]

Hi all, I just bought a set of "allegedly" 350 votec heads. My only problem is there isn't the easily identifiable "sawtooth" marks, just one round hump on each head. Casting numbers are correct, chambers look correct, but no sawtooth marks. Are they really 350 vortecs or not?
I saw the truck/engine they are from...97 chev, 5.7.

[clampjockey]

Pic #2

[clampjockey]

Pic #3

[clampjockey]

Pic# 4

[hugger6933]

Does it have bolt holes in the center, like where a heat crossover should be? Vortec heads only have four bolt holes ,two in front two in back around the front and rear ports, That is why the intake is different. that and the bolt holes are straight up and down on the Vortec. Jim

[clampjockey]

I can't say for sure...they aren't here atm. They came off of a 350 vortec engine, have the correct casting numbers, but no sawtooth marks. They wouldn't be 305 heads on a 350 engine? I assume the 305's have different casting numbers on their heads than the 350's.

[clampjockey]

There was a vortec intake on the engine, so they are deffinitely vortecs...but are they 350 vortecs? Did any 305 vortec heads have the same casting numbers as 350 heads?

[hugger6933]

They have a different chamber volume so no the numbers would not be the same.There were two different castings one was 906, I think and I don't remember the others. I do know that it will bring you about 40 hp on anything no matter what if anything else is done. If you had the whole motor and then changed out the cam for one similar to the LT4 hot cam, it would be on mean son of a gun. Jim

[clampjockey]

The other 350 votec casting number ends in 062 i believe. Some people prefer one over the other, others say there is zero difference power wise.... My only issue is the sawtooth marks, or lack of actually. Everything I've read says to look for the sawtooth marks....these have the round bump as seen in the pics

[clampjockey]

My plan is to actually stick em on an older block, with a 350 hp 327ci cam and a intake for votecs w/ a carb.

[clampjockey]

I found the answer for anyone else interested:
Casting # ending in 062 has sawtooth marks
Casting # ending in 906 has one large hump

[Acorn]

Do a quick google search. Every thing I read says it hat most of the flow numbers are a myth. Only difference is the 906 are used in heavier trucks and boats and have a hardened exhaust seat.

[clampjockey]

I'm not worried if one flows better than the other...all I was worried about was are they actual 350 vortec heads....I was under the assumption that both casting numbers had the "sawtooth" marks....these heads have just one hump.

[Acorn]

Looking at the combustion chamber, they are vortecs. Some had saw teeth and some had just one hump like yours.
Just don't forget you will need a bypass in the cooling system. Vortec heads do not have the same cooling port in the head.

[Acorn]

...

[Acorn]

http://67-72chevytrucks.com/vboard/s...d.php?t=651739

[clampjockey]

I was also under the impression that I could have the water jacket drilled on one of the heads to eliminate the cooling bypass...is this true?

[clampjockey]

Haha...that link is to my old thread that I started before I took my engine to get rebuilt....before I found out my "sawtooth" vortecs were cracked. So the pic in the link shows where to drill the hole for the water jacket....will doing this eliminate the need for the coolant bypass?

[Vintage Windmills]

I think that is unnessary. If you have the normal heater core (stock) setup and a non AC truck, you already have a bypass built in. You get flow from the manifold (through the head), to the heater core, and right back to the water pump. There is no coolant flow valve that can close in the heater core circuit.

[clampjockey]

It is an A/C truck, but i don't have the compressor and likely won't be hooked back up right away. I had no idea that made a difference.

[Vintage Windmills]

I think they have a coolant flow valve but am not positive.