454 vortec heads: which gaskets to use

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Slooptin

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Recently acquired a set of vortec heads and an Edelbrock performer rpm intake (oval port) and wondering which head/intake gaskets I need to get for these?
 

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Vortec gaskets. But if you plan to use these for performance purposes they are terrible. 454 vortec heads aren't like the small block vortec heads. The 454 ones are very low compression and poor flowing
 

bucket

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Vortec gaskets. But if you plan to use these for performance purposes they are terrible. 454 vortec heads aren't like the small block vortec heads. The 454 ones are very low compression and poor flowing

That largely goes against anything I've ever read or been told about them. The Vortec heads are not to be confused with the peanut port heads. They are supposed to be some of the better flowing oval port heads.
 

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I just so happen to have a set of Fel-Pro gaskets here for just that combination.
You must be registered for see images attach

I have a Mark IV 454 in my '79 truck and adding the L-29 heads will bump the compression up from a dismal 7.9-8.0 to a beautiful 9.0 to 1.
Much better in all respects.

Putting a better chamber on there will help in loads of ways that I have read from people that know far more about the subject than I do.
The intake ports are 235 cc or so which is larger than the peanut port heads for better flow from an untouched set.
The chamber is 20cc or so smaller for the nice bump in compression.
Internet sources state a 30-40hp increase by simply bolting them on.
You must be registered for see images attach

Well worth the price of junkyard heads combined with a cleaning and valve job.
I don't need giant port aluminum heads as it is still a truck, so these are a great deal.
 

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That largely goes against anything I've ever read or been told about them. The Vortec heads are not to be confused with the peanut port heads. They are supposed to be some of the better flowing oval port heads.
The small block ones are yes the big block vortec are more like. A swirl port but compression ratio would be so low they don't make power
 

bucket

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The small block ones are yes the big block vortec are more like. A swirl port but compression ratio would be so low they don't make power

Yes, I'm aware the small block Vortec heads are a different animal. They have nothing to do with the big block heads. But, the '96-up Vortec big block heads were a significant improvement over the previous TBI heads and 80's heads. They flow well and have the potential to make great power. There's been a lot of magazine articles and dyno testing that has proven that.
 

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Better off with a set of aluminum heads damn near same price after proper rebuild
 

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Rebuild is $600 for a pair here where I am currently.
Aluminum heads have 290 to 335cc intakes and are way to big for a truck that lives at low rpm most of the time.
 

bucket

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Rebuild is $600 for a pair here where I am currently.
Aluminum heads have 290 to 335cc intakes and are way to big for a truck that lives at low rpm most of the time.

Yeah, similar around here. Last big block heads I had shaved and redone were in the $500 range.
 

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Vortec bbc heads come with 99-100cc chamber giving a good compression bump. Work good for a truck application
 

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There are a lot of people selling aluminum, "who" do not want you to buy cast iron.
Period.

If you ever blow a hose, have a cooling system air bubble or a thermostat stick, (on a long drive), the threshold and the curve of heat to metal fatige ratio of a cast iron head vs aluminum, is not even close.

You can warp a $1200-$3500 aluminum heads driving as little as 30 seconds after the water hits 260-280 degrees and your gasket blows with hydro lock. Especially if you are on it.

All that white steam coming out of your exhaust is your head getting ruined, unless you stop and pull over immediately.

When you choose GM ***7.4L*** "Vortec Heads", they have a proprietary vortex cast into the intakes, which swirl the air flow for increased velocity.

30-40 hp is accurate, over Mark IV and V heads. This has been data logged on videos at dyno's by many quality builders.

If you are running a mild to towing camshaft, let's say under .500 lift in and out, the roller allows faster snap at the lifter and better efficiency, than let's say .520-.530, (in and out), using a flat tappet. Probably by a wide margin.

All this dope is saying is, rollerized torque cams, more towards the street able cams, with good vacuum, good performance and low end grunt for truck work loads, would probably be better off using quality GM Cast iron, over ANY aluminum head, period.

GM Manufactures aluminum heads. They manufacture and sell millions of them every year.
If it was worth it, for the power band, they would have sold them.

*** The problem with the aluminum heads is: GM Marketing Team, requires the heads to last five years or more for the warantee, in order to brainwash the consumer to buy them...***

Something tells me the freak expensive aluminum heads from the video I posted below; are NOT rated for 5 years...?

Bet, after working and filming at Lake X, where the "Gentlemen and Ladies" from Murcury Marine, build and test race boat engines; the guy selling heads in the video for $5K (per head), you most likely get a "walk out the door warantee".

"You break it; You Own It!"


If you have $5000 for the best designed 8.1L VORTE-X head(s), check out the ones that freak out the lemon 8.1L.
Bring your Nitro-Methane or Alcohol...

Please, Check thses video's out, so the rest of my post makes sense:

https://www.raylarengineering.com/cylinder_head.html
xc_hide_links_from_guests_guests_error_hide_media

It's the intake that makes the heads work, though...
xc_hide_links_from_guests_guests_error_hide_media

If your opinion is based upon the 8.1L heads, then you have a point, however not for the 7.4L L29 heads, used on the Mark V or Mark VI... and especially when used on the Mark IV...

The 7.4L head is NOT the 8.1L Vortec head.

Here's a great thread from 2019, where bucket was already a fan of the 7.4L L29 heads.
https://www.gmsquarebody.com/threads/vortec-454-7-4l-vs-vortec-496-8-1l.26940/

Can tell you from my personal experience, the reason for NOT using the 8.1L format:
The threads on the crankshaft bolt are proprietary pitch. It strips out very easy.

Was asked to service an 8.1L. It had already been abused by whomever replaced the timing chain and whomever used a breaker bar to rotate the engine to start it, after it developed a flat spot on the ring gear; (years before worked on it).

Wanted to pull the engine out, for good reason, because all the oil lines were shot and the ring gear needed to be serviced, (but only AFTER the rear main seal was replaced), and a new oil pump was installed with upgraded oil pump drive shaft, eliminating the plastic shaft connector crap.

Got over ridden. 220K on the engine... whay would you want to refurbish it, right?
Was humiliated because the other guy knew how to slide the transmission back and replace the ring gear, faster, cheaper better.
When everyone was made aware the crankshaft bolt was shot, from years of abuse, guess who they tried to blame?

The timing set was 120K on it, the oil lines were bleeding, the cir-clips and o-rings were shot every line on the engine.

Instead of reaming the threads and saving the crank, the next mechanic condemned the engine for complete replacement. It went back as a core, completely capable of being overhauled.

During the hundreds of hours of research I poured into the format, I found detailed threads, by quality machine shop owners, stating the 8.1L Vortec heads were not worth rebuilding. The rods were weak, the crank was weak and the heads needed for any power are the ones from above.

You might think my opinion of the 8.1L is not that good, but you are wrong.
The 8.1L, used, with a broken crank bolt, is the exact engine to rebuild with high horsepower parts for any offshore marine engine application.

8.1L can be made to sit with three others, with various rotational mods, using tunnel ram and blowers to drive your offshore boat to scary speeds.

Get this: If your building for offshore, (presuming you own a few helicopters and safety rescue diver's to chase you down when you flip), there are millions of them just waiting for the right wallet to make them great!

Getting the feeling what we have here is a mix up between formats, both using the Vortec name... cross mixed with referencing the 350... Sometimes, it really is rocket science, to figure it out.

Thing is, for many years, the most daring NASA rocket scientists came home in a boat.

*Edited the word "which" to "Who"... and a bunch of spelling errors...

If this saved you thousands of dollars on your big block Chevy Build, please respond with a Like.
 
Last edited:

bucket

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There are a lot of people selling aluminum, which do not want you to buy cast iron.
Period.

If you ever blow a hose, get an air bubble or have a thermostat stick, on a long drive, the threshold and the curve of heat to metal fatige ratio of a cast ion head vs aluminum, is not even close. You can warp a $1200-$3500 aluminum heads driving as little as 30 seconds after the water hits 260-280 degrees and your gasket blows with hydro lock. Especially if you are on it.

All that white steam coming out of your exhaust is your head getting ruined, unless you stop and pull over immediately.

When you choose GM ***7.4L*** "Vortec Heads", they have a proprietary vortex cast into the intakes, that do swirl the flow for increased velocity. 30-40 hp is accurate and has been data logged on videos at dyno's by many quality builders.

If you are running a mild to towing camshaft, lets say under .500 lift in and out, the roller allows faster snap at the lifter and better efficiency, than let's say .520 in and out using a flat tappet. Probably by a wide margin.

All I'm saying is, rollerized torque cams, more towards the street able cams, with good vacuum, good performance and low end grunt for truck work loads, would probably be better off using quality GM Cast iron, over ANY aluminum head, period.

GM Manufactures aluminum heads. They manufacture and sell millions of them every year.
If it was worth it, for the power band, they would have sold them.

If you have $5000 for heads, check out the ones that freak out the lemon 8.1L
https://www.raylarengineering.com/cylinder_head.html
xc_hide_links_from_guests_guests_error_hide_media

If your opinion is based upon the 8.1L heads, then you have a point, however not for the 7.4L L29 heads, used on the Mark V or Mark VI... and especially when used on the Mark IV...

The 7.4L head is NOT the 8.1L Vortec head.

Here's a great thread from 2019, where bucket was already a fan of the 7.4L L29 heads.
https://www.gmsquarebody.com/threads/vortec-454-7-4l-vs-vortec-496-8-1l.26940/

I can tell you from my personal experience, the reason for NOT using the 8.1L format:
The threads on the crankshaft bolt are proprietary pitch. It strips out very easy.

I was asked to service an 8.1L. It had already been abused by whomever replaced the timing chain and whomever used a breaker bar to rotate the engine to start it, after it developed a flat spot on the ring gear; (years before I worked on it).
I wanted to pull the engine out, for good reason, because all the oil lines were shot and the ring gear needed to be services, AFTER the rear main seal was replaced and a new oil pump was installed with upgraded oil pump drive shaft, eliminating the plastic shaft connector crap.

I got over ridden. I was humiliated because the other guy knew how to slide the transmission back and replace the ring gear, faster, cheaper better. When everyone was made aware the crankshaft bolt was shot, from years of abuse, guess who they tried to blame? The timing set was 220K on it, the oil lines were bleeding, the cir-clips and o-rings were shot every line on the engine. Instead of reaming the threads and saving the crank, the next mechanic condemned the engine for complete replacement. It went back as a core, completely capable of being overhauled.

During the hundreds of hours of research I poured into the format, I found detailed threads, by quality machine shop owners, stating the 8.1L Vortec heads were not worth rebuilding. The rods were weak, the crank was weak and the heads needed for any power are the ones from above.

You might think my opinion of the 8.1L is not that good, but you are wrong.
The 8.1L, used, with a broken crank bolt, is the exact engine to rebuild with high horsepower parts for any offshore marine engine application. It can be made to sit with three others, with tunnel ram and blowers to drive your offshore boat to scary speeds. Get this, if your building for offshore, there are millions of them just waiting for the right wallet to make them great!

I'm getting the feeling what we have here is a mix up between formats, both using the Vortec name... cross mixed with referencing the 350... Sometimes, it really is rocket science, to figure it out.

Yeah, see? I've wanted a set of those heads for years, lol.
 

RanchWelder

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Try this gentleman out...
https://www.powellmachineinc.com/

How we straighten a cam shaft
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Who actually Made Your Camshaft?
xc_hide_links_from_guests_guests_error_hide_media

How much does it cost to go Roller cam?
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Cam Design and Ramps, Let's unpack it some...
xc_hide_links_from_guests_guests_error_hide_media

What is your cam made of... Flat Tappet Investigation...
xc_hide_links_from_guests_guests_error_hide_media

It's what you don't know, will kill your engine.
Everything matters, all the time.

This the the guy you send the golden turkey too... Just sayin'... YMMV...
 
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RanchWelder

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Inertia, during lift, on a roller cam, will kill your cam, if you don't know what your doing.
Don't freak out: Ask an expert...

Oiling is everything... Never cut corners with oiling...
Every lifter is actually an oil filter and an oil pump.

Never buy cheap, or the wrong volume / pressure OIL pump... Buy what your build requires, nothing more...
If you don't know what your Build requires: DO NOT BUY ANYTHING.

Lifter's rule the world... get the correct ones and win.
Have the cam made by an expert?

YOU MAKE THE CALL...
 

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