Vortec heads

[gldevall]

Posted this in the engine forum also.

There is a set of vortec heads on ebay for sale that should be avoided.

http://cgi.ebay.com/ebaymotors/ws/eB...category=33617

I was reading an article from Chevy High Performance and they said the heads with the casting # 10239906 should be avoided.

Just a heads up so nobody wastes their money.

Link to article
http://www.chevyhiperformance.com/howto/97458/

[Tom]

Sorry, but your getting the dreaded

They took that article back a couple mags later, saying "sorry they really are all the same"

Because they are

[ElGracho]

Not only about the valve seats, but in that article they say you can only safely run .420 to .430 lift with stock vortec valve springs/guides. Now does that really make sense when the GMPP 330 hp crate engine runs .460" lift with stock vortecs? I don't think so. GMPP also says it's safe to run up to .475" lift with stock springs. They took that back too a couple months after they initially published the article you linked to.

[Izzy]

Lowrider had pretty much the same write up last month.

[gldevall]

Originally posted by fiveeightchevy
Lowrider had pretty much the same write up last month.

About them being the same or avoiding the ones with that particular casting #?

[gldevall]

OK new question. What is a head assembly? Does that include the rocker arms? or just the valves and springs?

[allthrtl]

Normally they don't come with rockers. Usually complete head assemblies will come with valves, springs, collars, keeps etc....but not always...Usually, they will say "bare" if they don't come with valves etc.....

[swervin ervin]

I'm pretty sure that GMPP upgrades the springs on the Vortecs when installing them on the crate engines. Not sure. Could be wrong, but I think I'm right. Personlly, I wouldn't even think of running stock Vortecs on a performance engine. What's the point? Sure, it will increase the hp over your old smog heads, but there is so much more to be had with just a little bit of money and work. If I'm going to the trouble to upgrade heads, I sure want to get all I can out of them.

I read somwhere before what the difference was in the two castings, or more importantly why they have different casting numbers, but I can't remember where I seen or what it said. It was a very long time ago.

[ElGracho]

Well, I guess the question here is what is a "performance engine". I've built two engines using vortec heads in the last six or so years.

The first engine was just to replace the goodwrench engine in my 84 that already had 140k on it (the truck now sits at 480k miles). I bought a rebuilt shortblock from a place in California. I was in Connecticut at the time and machine shop prices were outrageous. It was cheaper to buy vortec heads than have my old Goodwrench engine heads rebuilt. The fact that I ended up with 75 or more hp was a bonus.

The last engine I built (for my 86) I had another Goodwrench block bored, torque plate honed, zero decked, crank micropolished and balanced with forged pistons etc etc. I used a set of vortec heads and an RPM air gap intake. I figure I'm making at least the 330 hp that GM makes with their crate engine and hopefully a little more. After paying the bills for than engine, I wouldn't do that again, I'd go buy the crate version. It would be cheaper and have a warranty.

Anyhow, vortec heads are better than any other $500/pair complete head. The possible additional cost of the required intake and rockers still makes them tough to beat in performance per dollar for a rebuilt head. You'd have to spend a few hundred dollars more to get the same or more performance from other aftermarket heads. I'd call that more than just a little bit of money.

[Izzy]

Originally posted by gldevall


About them being the same or avoiding the ones with that particular casting #?

Same article stating to avoid that casting#. They stated in their article, "some Vortec heads were equpipped with a specially hardened exhaust seat that kills low- and mid-lift flow." Also stated " they lose 20% percent of their flow at 0.120-inches lift. "

[Jonboy]

you can buy the new vortec heads upgraded by Scoggin Dickey with Z28 springs, all bolts and necessary gaskets, and performer intake for $900 on their website. Pretty solid deal to me.

[Tom]

The problem with vortecs and valve lift is not the springs, but the valve guide. Its too tall and hits the retainer or inner dampner. I highly doubt GM machines down all vortec heads for the .460" 330hp motor or the ramjet 350 which also uses stock vortecs and has .481" with the stock 1.6 rocker arms.

Vortec heads are great for mild performance engines, in other words under 500hp. With about 4hrs worth of porting they can flow better then stock fastburn heads while retaining 170cc intakes [say hello to gobs of torque along with your HP]

[swervin ervin]

I wasn't talking about putting a little more in another set of heads, but putting it in the Vortecs. They are just a little weak on the exhaust side. And no Tom, they don't need 4 hours of work. And they are only good up to about 400 hp or so. After this, there are much better heads. If you are after 450 to 500 hp, do it right with a set of aftermarket heads.

Now, before everyone jumps on me, I think Vortecs are a great head. A little thin in the casting department, but so are any other late model stock head. Just don't ever let an engine with a set of Vortecs overheat.

What I meant by performance engine is one you are building for max power on a budget. With a couple hundred more bucks, you could have gained 125 hp or more.

[1972C10]

906s are the ones that everyone around here looks for.

[1FaastC10]

Originally posted by swervin ervin
Now, before everyone jumps on me, I think Vortecs are a great head. A little thin in the casting department, but so are any other late model stock head. Just don't ever let an engine with a set of Vortecs overheat.

as for the thinner casting, Mike you're right, they are a thinner casting. but, they are also fairly new, and a lot better designed than the traditional thin casting smog head that give the rest of them a bad rap. i wouldnt recomend overheating an engine at all, why would Vortecs be any different?

[swervin ervin]

I'm no dumbass. I know not to let any engine overheat.

Where do you come up with these wisecracks. I think you been hanging around Tim too much. You're starting to act just like him. :p

I meant most of the older heads would take heat and at the most warp. Vortecs will crack if they get too hot.

[jimfulco]

I thought they said the "bad" Vortec heads with the hard exhaust seat inserts were found in some of the heavy-duty trucks.

[1FaastC10]

well, with the overheating issues, since the Vortecs are a newer head, they probably havent been abused like the older thin casting heads. you can probably get away with overheating a thin casting a few times before it will crack, whereas a 20 year old head may crack the first time you overheat it.

i also noticed when reading through one of your previous posts you mentioned GMPP upgrading the springs. the heads are identical to the factory units, and even carry the same part number. so the GMPP heads carry the same max lift figure as the assembly line units.

[1972C10]

I gotta Agree the vortechs being computer designed Are bound to be better than something that was prolly mocked up in clay

[gldevall]

Originally posted by jimfulco
I thought they said the "bad" Vortec heads with the hard exhaust seat inserts were found in some of the heavy-duty trucks.

Yeah, the article stated the heads to avoid came on 3/4 ton and 1 ton trucks.