Restoring Rusty

[MikeB]

Originally Posted by Gregski

Basically the holes of the Vortec head and the holes in the Mr. Gasket gasket do not match up, in other words they are not the same exact size. I wonder how much of that bottom 3/16ths of meat could you grind down before hitting a water jacket...

Don't touch the exhaust ports! There is absolutely no benefit in doing so.

Vortec exhaust ports are raised relative to the header bolt holes compared to conventional heads. The trick is to find headers and gaskets that are "tall" enough. A huge percentage of exhaust flow is at the top of the port so it's imperative not to block the opening. As long as the gasket and header openings are the same size or a little larger than the head ports, you'll be fine. As I recall, 1.5" x 1.5" gaskets will work fine.

I used these stock 1997 replacement FelPros on my Vortec heads.


And then raised the ports on my cast iron manifolds.



An old racing trick where rules limit header primary tube size is to raise the headers on the head. Although this covers up the bottom of the head port, that loss is FAR outweighed by the gains at the top of the port where the denser and higher velocity gasses now have more room to move upwards and outward.

[MikeB]

Originally Posted by Gregski

Wow replacement GM Intake Valves part number 10241743 are $16 bucks a pop, EXPENSIVE!

Try pricing vales from Sealed Power or Competition products, Make sure they have only one groove.

Be sure to "lap in" the valves to the seats using valve grinding compound and a tool like this:
http://www.summitracing.com/parts/oe...2c4aAoYY8P8HAQ

[chevybuldr]

So a couple of things while looking at your heads just thru the pictures. The valve seat width is WAY to big to be able to lap the seats in. You want the width to be about .060. This is what a proper valve job comes into play to be able to fix this issue. a 30* top angle, 45* sealing and a 60* bottom. The pitting on the valve will need to be addressed and the valve refaced to the proper angle. The valves in your old heads are a little different then the Vortec valves. They have an O-ring groove below the keeper groove. While this will not hurt anything, they are not the same. The price for GM parts is crazy to aftermarket, valves should run you about 5-6 dollars a piece.

[Gregski]

Originally Posted by chevybuldr

So a couple of things while looking at your heads just thru the pictures. The valve seat width is WAY to big to be able to lap the seats in. You want the width to be about .060. This is what a proper valve job comes into play to be able to fix this issue. a 30* top angle, 45* sealing and a 60* bottom. The pitting on the valve will need to be addressed and the valve refaced to the proper angle. The valves in your old heads are a little different then the Vortec valves. They have an O-ring groove below the keeper groove. While this will not hurt anything, they are not the same. The price for GM parts is crazy to aftermarket, valves should run you about 5-6 dollars a piece.

let me preface what I am about to regurgitate by saying I dont know squat about this stuff, but I am learning so i appreciate what you shared

however I believe those specs are for a performance valve job not stock

Super Chevy article Angling For Power says:

"Using a dial caliper, we measured a seat width of 0.060 inch, which is a generally accepted street-engine spec."

it goes on to say

"Narrower seats generally improve flow but are also less durable."

[MikeB]

The below info is from a guy who was involved with Vortec head design and testing. As you can see, a single angle valve job is used only on the HD version of the 906 head for use in 1-ton trucks.

The #906 casting head was available in two versions. One has an Inconel exhaust seat with a single angle grind, and the other has the conventional 3-angle grind on the exhausts as per the #062. The #906 with Inconel seat does not intrude into the exhaust port. It was used primarily on the HD and 1-ton truck applications where sustained towing of heavy loads & weight up inclines could cause eventual damage to a standard induction-hardened exhaust seat from excessive heat.

The only difference between the #062 and #906 Vortec head is in the exhaust seat of the HD/1-ton truck #906 version, as described above. The #062 has a 3-angle grind on a standard induction-hardened seat, as does the non-HD #906 head. The 062 does flow slightly better on the exhaust side at low lifts but the advantage over a 906 is very slight. They both utilize back-cut exhaust valves. They both have 3-angle grind seats on the intakes with back-cut intake valves. Both heads make the same power in stock form.

Unless Super Chevy mag is now into 1-ton trucks, I'm not sure why they said what they did. ???

[Jake Wade]

The pitting on the sealing face of the exhaust valves is typically what you see from higher mileage use. You will have some leakage if not addressed.

I would send the heads out to have the seats recut and the valves ground(valve job).

You should not need to buy any valves unless you have one with pits too deep to clean up, stem wear under spec, or bent/out of round.

You also need to mic the guide boss OD to see what size seals you need. The ones you showed a picture of may work as they are designed to fit a size range.

[Gregski]

so feeling a bit overwhelmed with all the cylinder head science and it pouring rain outside I decided to price out some "Complete" brand new Vortec cylinder heads by Chevrolet Performance part number 12558060 to reassure myself I did the right thing by buying used heads, so here we go, follow along if you like this will be fun research.

Summit has the best price: $316.99 each

but looking at the pictures these heads sure had a lot of parts missing wouldn't you say?

Damper Spring Included: No
Rocker Arms Included: No
Rocker Arm Nuts Included: No
Guideplates Included: No

so we gots to add $24.99 for the Rocker Arm Kit GM part number 10089648 times 8 per head so $199.92 extra

so our new actually assembled and really complete heads now cost $516.91 and I stole mine for 1/10th the price, though they did come with their own set of [ahem] HEADACHES! ha ha

man I sure the good ol' days where we said what we meant and we meant what we say, non of this partially "complete" nonsense, or WiFi ready (I'm looking at you Panasonic)

[chevybuldr]

Originally Posted by Gregski

so feeling a bit overwhelmed with all the cylinder head science and it pouring rain outside I decided to price out some "Complete" brand new Vortec cylinder heads by Chevrolet Performance part number 12558060 to reassure myself I did the right thing by buying used heads, so here we go, follow along if you like this will be fun research.

Summit has the best price: $316.99 each

but looking at the pictures these heads sure had a lot of parts missing wouldn't you say?

Damper Spring Included: No
Rocker Arms Included: No
Rocker Arm Nuts Included: No
Guideplates Included: No

so we gots to add $24.99 for the Rocker Arm Kit GM part number 10089648 times 8 per head so $199.92 extra

so our new actually assembled and really complete heads now cost $516.91 and I stole mine for 1/10th the price, though they did come with their own set of [ahem] HEADACHES! ha ha

man I sure the good ol' days where we said what we meant and we meant what we say, non of this partially "complete" nonsense, or WiFi ready (I'm looking at you Panasonic)

Rocker arm kit should come with all 3 pieces that you need, rocker arm, rocker ball and the nut.

You can not run a guide plate on those heads unless you have them machined for screw-in studs and guide plates. Then you would have to run a non-self aligning rocker arm (early version).

[hatzie]

They're complete heads for an engine buildup. No machine work necessary.
They assume you'll be completing them with shaft mount roller rockers. They're around $240. No need for guide plates with those.

[rich weyand]

The valves and seats look fine to me compared to a 110,000 mile engine I rebuilt. Those valves and seats needed grinding, and I just happened to know a guy who worked at a place with the correct machinery who was willing to trade favors.

Just lap the valves and put it all back together. You'll be fine.

Lapping would be the first thing I would try anyway. You'll be able to tell looking at them after lapping what kind of seal you've got.

[Jake Wade]

A $200 (on average) trip to the machine shop for cleaning, crack test, resurfacing, and valve job will have your heads like new, assuming they are not cracked.

[chevybuldr]

Originally Posted by Jake Wade

A $200 (on average) trip to the machine shop for cleaning, crack test, resurfacing, and valve job will have your heads like new, assuming they are not cracked.

I would have to agree with you on this.

[MikeB]

Originally Posted by Gregski

Feeling a bit overwhelmed with all the cylinder head science and it pouring rain outside I decided to price out some "Complete" brand new Vortec cylinder heads by Chevrolet Performance part number 12558060 to reassure myself I did the right thing by buying used heads, so here we go, follow along if you like this will be fun research.

Summit has the best price: $316.99 each

but looking at the pictures these heads sure had a lot of parts missing wouldn't you say?

Damper Spring Included: No
Rocker Arms Included: No
Rocker Arm Nuts Included: No
Guideplates Included: No

• You don't need guide plates, only self-aligning rocker arms which you already have, assuming the valve stem tip contact surfaces aren't too worn.
  
• Stock Vortec springs do not require dampers. Springs are good to a approx .480" lift + a safety margin, and are good to 5500 RPM or so. They are the same springs used on the RamJet 350.
  
• The nuts that came with your heads are probably better than aftermarket nuts which don't grip the studs as tightly.

Have you considered conventional heads for use with the intake manifold and valve covers you already have?

[Gregski]

The valve seals showed up today GM part number 10241743 got 'em for a song $12.99 on eBay and FREE shipping - good things come in small packages I guess

[Gregski]

completely disassembled the second head today, the Driver Side

[Gregski]

lets check out these studs a bit closer shall we

[Gregski]

ok lets check out the combustion chambers, look closely

[Gregski]

Noooooooooooooooooooooooo

[54earl]

Mother trucker

[chevybuldr]

Originally Posted by Gregski

Noooooooooooooooooooooooo

Thats a bummer. Main reason why you need a machine shop to magna flux them for cracks like I said earlier.

[Gregski]

Originally Posted by 54earl

Mother trucker

LOL, last chamber I cleaned too, we was almost out of the woods

[Gregski]

Originally Posted by Chaplain

Oh my...

I am kicking myself for not buying a second set of these Vortec heads I just saw recently already pulled at a junkyard, just laying there in the back of some Suburban

[Gregski]

Originally Posted by chevybuldr

Thats a bummer. Main reason why you need a machine shop to magna flux them for cracks like I said earlier.

I hear you, I just really wanted to go through this at least once on my own, successfully that is, so this don't count

I did call a number of shops in Northern Califirnia and a basic head job runs us $250, thats hot tank, magnaflux, and put back your old parts plus the seals I provide myself, I guaranty you seldom they put your old parts back in

[enaberif]

#1 issue with vortec heads.. cracks like that and you never know till you bought them.

you now need to replace that cylinder head or take it back for a exchange.

[chevybuldr]

Originally Posted by Gregski

I hear you, I just really wanted to go through this at least once on my own, successfully that is, so this don't count

I did call a number of shops in Northern Califirnia and a basic head job runs us $250, thats hot tank, magnaflux, and put back your old parts plus the seals I provide myself, I guaranty you seldom they put your old parts back in

A good quality shop will not rip you off on parts. They make more money with you returning as a happy customer. Also they have to show you your parts that are no good when you ask. There are a lot of crooks out there, but there are also a lot of good quality shops out there. Call around and ask how much it costs to check out a set of heads. It would be my guess though that the exhaust valves will need to be replaced.