Lets talk about intake gaskets . . . . .

[rp930]

Manifold fit was fine. Block has not been decked, light cut only on the heads. Bolts line up perfectly.

I used the stock replacement Fel Pro gaskets. Its ready to go out the door Glad I was not the only one rethinking this.

I’m sure the stock gaskets will work fine. And they aren’t brittle like the blue stripe gaskets get.

[Schurkey]

2022_K1500_Intake_Gasket_08.jpg

2022_K1500_Intake_Gasket_23.jpg

This was the second time I replaced these. First set I blamed on me using the wrong gaskets--1205s. These are the correct port size for the heads--1256, I think. I was not happy.

But I can't rule out a warped/twisted intake manifold (ZZ4 aluminum). Anyway, the third set seems to be holding.

Sucked the wrong way, intake backfire ?

No...Ran good until the gasket pushed out enough to cause vacuum leaks.

[Tom68]

2022_K1500_Intake_Gasket_08.jpg

2022_K1500_Intake_Gasket_23.jpg

This was the second time I replaced these. First set I blamed on me using the wrong gaskets--1205s. These are the correct port size for the heads--1256, I think. I was not happy.

But I can't rule out a warped/twisted intake manifold (ZZ4 aluminum). Anyway, the third set seems to be holding.

Sucked the wrong way, intake backfire ?

No...Ran good until the gasket pushed out enough to cause vacuum leaks.

Surface finish in relation to gasket type I guess is at play unless the heads were angle milled, but even then the whole section slid up, too smooth a finish for the gasket type.

Put oem spec Victor Intake gaskets (orange ? deacades ago) on a SBC, jut about needed a jack hammer to get the manifold off, tore them to bits getting it off, lots and lots of scraping, they bonded themselves rock solid.

[rgalajda]

This leads me to ask.
Has anyone on here ever used the angle check tool? http://bhjproducts.com/index.php?main_p ... cts_id=397

Has anyone on here ever used the lead shot test?
https://www.enginelabs.com/engine-tech/ ... fold-seal/

Why not?
How do you know the intake manifold is fitting correctly?

[leahymtsps]

They were doing that 15 yrs. ago and still doing it today. That is at least in endurance applications.

[rgalajda]

They were doing that 15 yrs. ago and still doing it today. That is at least in endurance applications.

Doing what?

[skinny z]

It seems not all Fel-Pro Performance Intake Gaskets are created equally.
The 1205 has the printoseal blue bead around the ports.

Fel-Pro 1205.jpg

1205

The 1255 version (for Vortec style heads) doesn't have that bead.

Fel-Pro 1255.jpg

1255


Both are listed as the Performance line.
Not sure about the 1205 but when using the 1255, which is just some kind of composite paper, I used Gasgacinch around the ports. Provided fitment is OK, those suckers have never leaked. Evidence is in the removal as those gaskets are stuck on everywhere. A little RTV around the water ports too.

Is there a paper 1205 equivalent without the bead?

[Tom68]

Was it Bill Jenkins that used to center punch around the inlet ports ?


As we know from Erics manifold testing we don't want the manifold roof higher than the port roof.
Gasket thicknesses.

20240114_074056.jpg

[skinny z]

Was it Bill Jenkins that used to center punch around the inlet ports ?

As we know from Erics manifold testing we don't want the manifold roof higher than the port roof.
Gasket thicknesses.

20240114_074056.jpg

I don't know about "Da Grump", (although having followed his exploits through the peak of his career), what I can say is that the 120 thou gasket pictured above is what got my intake into good alignment with the heads (Vortec equivalent). As per Weingartner but my fitment was before Eric's video. I've a .060" plastic style carrier gasket with a printoseal I could have used but the shape around the ports just seems all wrong. That's despite it's listed as an OEM replacement for GM's Vortecs.

[Tom68]

Had to ask ChatGPT.

Who recommended center punching intake manifold faces to stop gasket slippage
ChatGPT
Center punching intake manifold faces to prevent gasket slippage is a technique often recommended by experienced mechanics and automotive enthusiasts. The idea behind this practice is to create small indentations or dimples on the intake manifold surface, which helps the gasket stay in place during installation and prevents it from slipping out of position.

The recommendation is usually based on the observation that some intake manifold gaskets have a tendency to move or shift during installation or while the engine is in operation. This movement can lead to leaks and affect the performance of the engine.

By center punching the intake manifold faces, you create reference points or marks that align with corresponding features on the gasket. This alignment helps keep the gasket securely in place during installation, reducing the likelihood of slippage.

It's important to note that while this technique is a common practice, not all engine designs or gaskets may require it. Always refer to the specific recommendations provided by the engine manufacturer or consult with experienced professionals who are familiar with the particular engine and gasket combination you are working with.

User
Was it Bill Jenkins or Smokey Yunick
ChatGPT
The practice of center punching intake manifold faces to prevent gasket slippage is often attributed to Smokey Yunick, a legendary NASCAR mechanic and car builder. Smokey Yunick was known for his innovative and unconventional approaches to automotive engineering and racing. However, it's essential to note that specific techniques and practices in the automotive world often involve contributions from multiple individuals over time.

While Yunick is commonly associated with this method, it's possible that other mechanics and engine builders, including Bill Jenkins, may have also used or recommended similar techniques. The sharing of ideas and practices is common in the automotive community, and the attribution of specific methods to a single individual can sometimes be challenging. In any case, both Yunick and Jenkins were influential figures in the world of motorsports and made significant contributions to automotive performance and technology.

[ChopperScott]

I've read about those same gasket sealing issues, but haven't had any problems myself. Here are a few SBC gaskets I have on hand...
-1289
-1207
-1266
-1206
-1206S-3
-1205S-3
-6901
-6900

IMG_9252.JPG

[skinny z]

I've read about those same gasket sealing issues, but haven't had any problems myself. Here are few SBC gaskets I have on hand...
-1289
-1207
-1266
-1206
-1206S-3
-1205S-3
-6901
-6900

IMG_9252.JPG

Third from the top. Is that the 1266? If it is, that may be a series indicator to a composite paper gasket without the printoseal. Similar to the 1255 I posted earlier.
If it is, that could be a bit of a problem solver in that it could be glued down (as in Gasgacinch) rather than relying on the bead of silicone of the other gaskets.
Just throwing that out there for the OP.

P.S. Scott, you need more gaskets on hand!

[Tom68]

P.S. Scott, you need more gaskets on hand!

Yer, everybody should have a set of 1255s.

[Bill Chase]

It seems not all Fel-Pro Performance Intake Gaskets are created equally.

Is there a paper 1205 equivalent without the bead?

You can get the 1205s3. @ .065" vs the 1205 @ .060. the s3 denotes a steel core.
You can also get the one that works with 55-86, and Vortec heads. but it is substantially thicker from Fel Pro.

Summit has a search engine that allows you to enter port heights and widths. For the mild street sbc heads there are probably over 150 different gaskets available from various manufacturers, the majority of them are designed for 1204-1205 size ports.

[leahymtsps]

They were doing that 15 yrs. ago and still doing it today. That is at least in endurance applications.

Doing what?

Splitting