Vortec Heads???

[blazzin72]

I'm am in the middle of a top end job on the 72 Blazer and started thinking..... would vortec heads be worth the cost? I'm guessing about a 400 - 500 bump in cost.... I'm told I'd gain 30% in HP and some fuel economy? Has anybody done this and what were the results????


T

[aesj2]

Don't count on 30% H.P. More like 20%. Little more mpg. You will need to modify or replace your intake manifold. The center bolt's are NOT angled, they are stright up. Cost for heads and correct manifold more like $800. Good Luck.

[bigjimzlll]

the vortecs will raise the CR by 1 full point..which will help,but will take higher octane fuel. with out a cam change you will pick up some HP. Probably from 240 to 275 or so. with a cam change..over 300, with proper exhaust

[Mudder]

I just did this. Vortecs, roller rocker and edlbeock airgap (sorta over kill imo) and tried to run the 670 truck avenger but had no luck. After calling Holley they talked me into a 770 street Avenger. It really does run a lot better. Dont know about gas tho. I do have to burn the good stuff. It'll smoke the tires on a 4x4 with 35's.

[70 longbed]

Super Chevy ran a series about 18 months ago, where they built a 350, then added this part, then that part, and so on; each time they dynoed the engine. Really good article because it was all the stuff that we add; headers, dual exhaust, intake, etc. It was the vortec heads that did the trick. My neighbor is the local Chevy service manager, and also drag races a 350. He says that early model vortecs flow all most as well as the new Corvette heads and some of the more expensive aluminum heads that you buy aftermarket.

I did the something similar to Mudder; 350, .125 pop top hypereutechtics (sp), bored .30 over, airgap intake, edlb 650cfm, and a good size cam, and desk top dyno put me around the 400hp mark. I really don't believe it, and have even decided against the vortec just for the reason of having to modify my intake. Maybe when I get everything put back together and run my regular heads, I can switch out to the vortecs, and have it dynoed again.

In the meantime I have a set of rebuilt vortecs with 1.5 and 1.9 valves, new seals, new (stiffer springs) set up for the 1.6 roller tip rockers I was going to use, for sale; $450 +shipping, or make an offer that I can't refuse.

[72k5]

Careful...

That thinking gets expensive! I went to rebuild the TH 350 in my 72 Blazer, then I got to thinking. I ended up swapping in a 700r4. I figured I should stop the oil leaks on the motor while it was out for the 700r4 install, then I got to thinking I should check the bearings (they were fine) and do something about a head with a slight antifreeze leak. So, I thought I might as well rebuild it. Then I thought Vortec heads and some D cup pistons woud be good. Then I thought some Edelbrock E tec heads would really be the way to go, and not much more expensive. I thought I might as well get the roller rockers since I went this far. Then I thought I should protect the exhaust threads in those aluminum heads with some good Thorley TriY headers. So I thought that I really needed to rework the exhaust for that to be right.

I'm not quite done yet, but I think I need to stop thinking!

[Mudder]

Thinking can get very expensive!!!!!!!!!!!!!!!!!!!!!