Vortec Heads vs OEM SBC Old School Heads

[crazy4offroad]

I get tired of posting this link because I feel like noboby reads it, but here I go posting it yet again...
http://www.onedirt.com/tech-stories/engine/a-guide-to-vortec-vs-oe-small-block-chevy-heads/
The charts near the bottom with the flow numbers tell the tale. But read the whole thing, you may find yourself bookmarking it too like I did.

 

[HotRodPC]

Thanks for the wealth of great info C4. I copied the link to a new thread and its worth being STUCK !!! Got'R Done !!!

 

[Dave1978]

I like the vortec heads as well I have a set on ice for my next truck engine project.I read a test in a magazine years ago that tested all of GM aftermarket heads and they out flowed most.They are nice also with the center bolt valve covers cuts down on oil leaks a lot.

 

[Jims86]

The only problem is; They nail you in the ass for an intake manifold.

 

[HotRodPC]

Yep, but still glad there is an aftermarket intake that allows the use of Vortec heads on old school motors. The only other drawback I don't like about Vortec heads is the max lift issue. Got a great head, but can't run a biggo cam with them without extensive expensive machine work.

 

[GreaseDog]

Yep, but still glad there is an aftermarket intake that allows the use of Vortec heads on old school motors. The only other drawback I don't like about Vortec heads is the max lift issue. Got a great head, but can't run a biggo cam with them without extensive expensive machine work.

During valve guides down is cheap.

 

[HotRodPC]

During valve guides down is cheap.

It that all that is required? I thought the valve spring seats had to be recess cut deeper and also wider?

 

[foamypirate]

It that all that is required? I thought the valve spring seats had to be recess cut deeper and also wider?

For certain springs, maybe. But for most springs you just machine the valve guide down so the retainer doesn't make friends with it.

 

[HotRodPC]

For certain springs, maybe. But for most springs you just machine the valve guide down so the retainer doesn't make friends with it.

Cool, I thought the machine work was much more extensive than that. I was wanting to run about a .525 lift and .310 duration cam, and thinking I'm toning down to about a .510 .300 duration. Also want about 11 to 1 to with valve overlap, I should be OK with 89 pump gas, so Vortec heads would be for me. I want the sleeper effect or at least appearance since with that cam, it won't be no sleeper for sure. It'll be a biggo bumpitty bumpitty bump idle to it.

 

[Dave1978]

intake

The only problem is; They nail you in the ass for an intake manifold.

I've seen them as cheap as $75 on Ebay the ones to convert the heads to run with a carb.

 

[Guardian]

Cam reccommendation

HotRod PC I have a 500+ lift in mine and it is a sleeper, most don't notice it. It is the Lunati Vodoo roller, it runs well on pump gas.

 

[HotRodPC]

HotRod PC I have a 500+ lift in mine and it is a sleeper, most don't notice it. It is the Lunati Vodoo roller, it runs well on pump gas.

Being roller helps on making sleepers. Also other specs like lobe seperation help too. Do you know which cam grind you have???

 

[Guardian]

Yes, it is a VDSC-262. The seperation is 112.

 

[HotRodPC]

Yes, it is a VDSC-262. The seperation is 112.

Certainly a good low end power cam, but it doesn't appear to be roller, and doesn't provide over .500 lift. It can get that kind of lift with 1.6-1 rocker arms though. Maybe you just have roller rocker arms and they are 1.6-1 rockers if someone has told you it's a roller cam with over .500 lift.

http://www.lunatipower.com/Product.aspx?id=1983

 

[Guardian]

It is a 507/515 lift roller. I double checked the grind number from the card, VDSC-262. It does make a ton of low end, but I wanted to make sure it could be used as a daily driver.