are all small block chevy votec heads the same?

[dj_joker_2002]

Just curious here but I bought a set of L31 vortec heads and have them on a 305. They have 194 valves and was just wondering what the difference is between 305 and 350 vortec heads. I just received a 350 from a 1995
chevy 30 series van for free so I may build it and install it in my new project.

[robertg]

quoted from http://www.hotrodders.com/forum/305-350 ... -4556.html

The 305 Vortecs have smaller runners, smaller chambers, and smaller valves, They would still work nicely, but wouldn`t give the full potential of the 350 Vortec head. this is what it says in Chevrolet High Performance.

[dj_joker_2002]

OK update : according to my friend who is a parts man at the local GM dealership the L31 vortec heads are the same for 305 or 350's from 1997 to 1999 they all came with 194 intake valves and they all were the same as far as runners and such. mid way through the year 1999 they redesigned the 350 versions for high torque for the trucks and such. The version that was sold over the counter was not the same as the factory installed versions but he didn't elaborate on what the difference was. So my heads are 1997 L31's so they will work fine on the 350 I am building.

[6spd_monte]

Check out this article by Sallee Chevrolet. They have edited a Chevy Hi Performance article to clear up the confusion regarding vortec casting numbers vs part numbers.

Link

It's some good info.

[Rebel]

The 95 350 heads,,do they have 4 bolts on each side of the intake or 6 ?

[dj_joker_2002]

I will check the numbers on both the vortec heads and the 350 stockers and get back to you guys tomorrow. I will also check the intake bolts on the 350 stockers. Mark

[dj_joker_2002]

The heads are factory 350 vortecs that I had on the 305
the heads on the 95 350 are 12 bolt intake variety 350 heads, I have yet to take the valve covers off the 350 as I recently had surery and can't lift anything for 2 weeks.

[Rebel]

Here is the explanation Mr_Roboto gave me on the 12 bolt intake heads when I asked what I had.

Those should be swirlies not Vortecs in all honesty. If you have one pull a valve and see if they have the ramps in em. No not the best head but if you're willing to take the grinder to em I'd use em. The other thing is that look at the number of intake bolts all production vortec heads have 4 not 6 bolts per side.