What are the casting numbers on Vortec heads?
Vortec cylinder heads have the casting numbers located near the valve springs. 14020555: 1981 305ci, 58cc chambers 1.84/1.50-inch valves. 14020556: 1981 350ci, 78cc chambers, 1.94/1.50-inch valves. 14022056: 1985 350ci, 78cc chambers, 1.94/1.50-inch valves.
Are there different Vortec heads?
Types of GM Vortec Heads The Vortec heads are a little bit lighter than the older heads and have a “kidney” or “heart” shaped combustion chamber that is more efficient than the double hump chamber. L31 Vortecs comes in two different casting numbers, 10239906 (#906) or 12558062 (#062).
What is the difference between Vortec heads and regular heads?
Vortec Intake Valve Seats and Combustion Chamber The Vortec combustion chamber is a kidney-shaped design that promotes better combustion and will have the spark plug located near the center of the chamber. The regular 350 head utilizes a 90 degree intake bolt angle while the Vortec makes do with a 72 degree bolt angle.
How do you identify Vortec heads?
Vortec heads are easily identified, as they only have 4 intake manifold bolts per side that are straight up compared to the older style which used a 6 per side intake mounting that are angled. Real Vortec heads were introduced in 1996.
What year 350 has Vortec heads?
From 1996 to 2000, GM truck and van 350 engines came equipped with L-31 Vortec cylinder heads.
Do Vortec heads need guide plates?
Registered. If you want to use guide plates on the SBC Vortec heads they need to be machined to use the plates.
What years did Chevy use Vortec heads?
From 1996 to 2000, GM truck and van 350 engines came equipped with L-31 Vortec cylinder heads. Built of cast iron, these powerhouse heads upped the horsepower of these engines by magnitudes.
What’s the difference between a 350 and a 350 Vortec?
The regular 350 head uses a 90 degree bolt angle while the Vortec uses a 72 degree bolt angle. When the head is bolted to the engine, all the attachment bolts point straight up, as experienced mechanics know.
Do roller rockers need guide plates?
guide plates. Since you’ve chosen the roller rockers that require guide plates, you now have to either run guide plates to keep them aligned, or swap to self aligning rockers to use with the stock head setup. You’ll also need hardened pushrods with guide plates, but don’t need them with the stock head holes.
Do Vortec heads need screw in studs?
No need to machine the stud boss if you dont want guideplates. You just need to tap them and there are studs without the hex jam nut.
Where did the Vortec 906 flow heads come from?
I got my 906 casting vortec head back from the machine shop. Same shop and same SF600 flow bench that flowed my 601 heads. Those are 305HO heads. The Vortec heads came off a 1996 chevy truck Virgin. I did not do any valve or seat grinding all I did was a bowl port and thin the guides and lap the factory valves.
What are the casting numbers on a Vortec?
Here’s a quote from the link above: “The L31 Vortec comes in two different casting numbers, 10239906 (#906) or 12558062 (#062). Originally, the stock #906 casting head was available in two versions. One version had an Inconel exhaust seat with single angle valve grind and was available on 1 ton trucks.
What’s the difference between a Vortec 062 and a 906?
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.
Is the 906 casting head the same as the 062?
Originally, the stock #906 casting head was available in two versions. One version had an Inconel exhaust seat with single angle valve grind and was available on 1 ton trucks. The other version was the traditional three angle valve grind. Other than that, the #906 is the same as the #062 head.”