Vortec head help

[72kool]

So I have a stock 350 in my '72 C20. It has 68000 miles and runs pretty good (idles high,needs adjusted)

I had a post years ago about a vortec head swap and hitting close to 400hp for $1500.

Well a few years later, another kid and new home, truck money is non existent right now.

So my question is, I have a set of 096 vortec heads. What is the minimum cost way to do this swap? I know I need a vortec intake and need a better cam to compliment the head swap. Otherwise I won't gain much. But what do I need to do to the heads? What parts HAVE to be changed on the heads to work? Do I need to have the whole engine rebuilt or can I justify a cam and head swap and not touching the lower end? The engine runs good and my only complaint are oil leaks. Can I leave it alone and just change the leaking gaskets?

[truckster]

If you don't go above the max lift (I think it's .450) you don't have to modify the heads at all.

You'll need a new temp sending unit.

If the bottom end is in good shape you don't have to do anything with it.

[B. W.]

To hit the 400 hp mark, you''ll need to up the compression ratio (pistons) A roller cam would help also. But if you just want to swap the heads I would, at minimum, do a compression test before removing the old heads. A cylinder leakdown test would be even better. You can buy leakdown gauges cheap now but I'd borrow one if possible because you hardly ever use them. These tests are good indicators of a sound motor. Oil pressure is another indicator, as the bearings begin to wear, the bearing clearance increases & the oil pressure decreases.

So, in short, if you have good compression, you're not burning oil, you have good oil pressure & there aren't any bad noises, the bottom end is in good shape.

As for the heads, you can run them stock if you stay mild on the cam. Too much lift & it crunches valve stem seals. Plenty of reading on this.

You might see a decent gain by just swapping heads, IDK what the volume of your stock heads are (maybe someone will chime in) but the vortecs should give you a bump in compression & they flow very well.

Finally, not wanting to be a buzz kill, almost every used vortec head out there is cracked. I'd have a machine shop check them.

[72kool]

I was going to.have the heads rebuilt no matter because it's my major unknown. At least the engine block I can test and I've driven many miles on it and have not had any issues.

What would be a good suggested cam to get that would maximize the heads in stock form?
If they clean the surface of the heads and rebuild them, with a virgin stock block, what thickness head gasket should I use?

[Captainfab]

While the heads are being rebuilt, have the guides machined to allow more valve lift and check into better springs to also allow more valve lift. Summit racing has a couple sets of their house brand spring kits for reasonable. For a cam, I would go with a Comp XE262, a XE268 or Lunati equivilant.

[72kool]

What do I need for springs? Also what lifters? Just get some with the cam or go back to stock?

[B. W.]

You should match the springs to the cam your running. Once you decide on the cam see what the manufacturer recommends. Lots of options, some inexpensive.

For lifters, either / or. The last few motors I built were vortecs. I used stock GM lifters.

X2 on Captainfab's cam suggestions, you'll need to cut down your guides.

[PebbleHill]

PM me. I just sold a budget 355 with vortec heads that ran 6.94 at 94 mph in the 1/8 with a 1.59 60ft. Vortec heads work great !

[chevy_mike]

Originally Posted by PebbleHill

PM me. I just sold a budget 355 with vortec heads that ran 6.94 at 94 mph in the 1/8 with a 1.59 60ft. Vortec heads work great !

Why don't you post up your info so everyone can learn something.

[truckster]

My machinist installed stock SBC valve springs in my Vortec heads, primarily for spring pressure (100 lbs vs. 70 lbs.) but that also limits possibility of binding springs.

He also said he's seen very few used Vortec heads that don't have cracks. The ones I brought in were 906 castings from a 1 ton, so they came from the factory with hardened seats. They were cracked anyway.

[AcampoDave]

Maybe i am the buzzkiller here. You said money is tight and you're motor runs good. (I wish we had an emoji for a can o'worms because I could use one in my post.) If the engine is old, I would just fix the leaks and roll on. Doing things on a shoestring budget seldom yields optimum results. I already see dollar signs rolling on machine work, intake, cam, lifters, gaskets, antifreeze, oil, filter, and an assortment of miscellaneous crapola which is sure to spring up. Then what if things don't work out like you wanted...(this happens when putting new heads on old motors) and then next thing you know you're trying to justify the expense of a total rebuild. I say focus on the family and enjoy the truck for what it is.

[garyd1961]

Originally Posted by AcampoDave

Maybe i am the buzzkiller here. You said money is tight and you're motor runs good. (I wish we had an emoji for a can o'worms because I could use one in my post.) If the engine is old, I would just fix the leaks and roll on. Doing things on a shoestring budget seldom yields optimum results. I already see dollar signs rolling on machine work, intake, cam, lifters, gaskets, antifreeze, oil, filter, and an assortment of miscellaneous crapola which is sure to spring up. Then what if things don't work out like you wanted...(this happens when putting new heads on old motors) and then next thing you know you're trying to justify the expense of a total rebuild. I say focus on the family and enjoy the truck for what it is.

Smart man^.

[mattfranklin]

There was a Car Craft issue a few years ago where they overhauled a complete Vortec V-8 junkyard motor on a budget. Although it was high miles it had good iron and design, so the wear was low and didn't need much if any machine work. Basics were cleaning plus new rings, bearings, and gaskets. Then for power they added a cam. If I remember, they needed only the cam because the stock rollers could be reused. And they gave it an intake to adapt to a carburetor. They made an easy 300hp.

Something like this you could do slowly over time as budget allowed in your garage while enjoying driving with the existing engine. Then when it was finished you could swap it in a weekend with very little down time for your truck.

EDIT
Here's the article:
http://www.hotrod.com/articles/how-t...l-block-chevy/