lower intake gasket question

[Couger1968]

Re: lower intake gasket question

They are under the valve covers. I think there is a 99% chance that they are lb4. Even if they are l35 you can still use the Lb4 gasket.

 

[dgoodhue]

Re: lower intake gasket question

O so l35 heads are stock on some ty? Sorry I'm new to this tryingto learn.

No L35 from the factory. It was a rumor for w long time that some late 93 had them but it was never true.

 

[Slyclone]

Re: lower intake gasket question

Magnum is for l35.

1202 if still available is what you need.( stock)? I don't know anything else that works I used some ms933? And had a lot of trouble with it. The correct intake gaskets they don't even make anymore! They looked like asbestos material!! You will knpw it whem you see..A good pratice is to note everything you see, like note if there has been replaced gaskets and engine was opened up.. After I struggled... And eventually sold the truck A set of the real McCoys ( the asbestos looking gasket) popped up. Its the way it works.

Keith sent me the info in regards to the Magnum gaskets about 6 mons ago when I was stressing out about my typhoon.

 

[JoeSupra]

Re: lower intake gasket question

So confusing. Lol if l35s arnt factory then the magmum kit might work because why would they make a gasket kit for a Frankenstein setup?? The kit looks to be decent. I called them to see if they can give any info on their kit. Maybe I could talk them into making the right ones when I take of my stock one...that's if mine are stock.

 

[Couger1968]

Re: lower intake gasket question

I used Fel-Pro MS93346 on my L35 conversion and have not had any trouble. I don't have a ton of miles , but it has been a couple of years and about 2500 miles.I think the 1202 are also fine and a lot of people use them and are readily available. You would need to open up the egr passages if you would like to use it with the 1202. The magmum MS18103 gasket is close to stock looking.

 

[SY-1193]

Re: lower intake gasket question

LEFT for L35 Heads MAGNUM PN: MS18094
RIGHT for LB4 Heads MAGNUM PN: MS18103

See the radius in the top of the ports on the L35 (left set).

These gaskets have metal in them for strength.

Joe (Slyclone) asked me to clarify.

 

[JoeSupra]

Re: lower intake gasket question

LEFT for L35 Heads MAGNUM PN: MS18094
RIGHT for LB4 Heads MAGNUM PN: MS18103

See the radius in the top of the ports on the L35 (left set).

These gaskets have metal in them for strength.

Joe (Slyclone) asked me to clarify.

Thank you! I will look into gettin the MS18103 Seems other gaskets dont have other ports cut out. But these lb4 magnums seem to be almost correct. According to Magnum l35s are for 93 and lb4 is 92. I have a 93 but I should still get the lb4 gaksets right?

 

[SY-1193]

Re: lower intake gasket question

Thank you! I will look into gettin the MS18103 Seems other gaskets dont have other ports cut out. But these lb4 magnums seem to be almost correct. According to Magnum l35s are for 93 and lb4 is 92. I have a 93 but I should still get the lb4 gaksets right?

Short Story: YES.
Long Story and disclaimer....yes, as long as no one has changed the heads on your truck.
Only you know the answer. Read the posts above about checking the head part numbers located under the valve covers cast in the metal of the head material. The only way to know for certain.

Bottom line...run whatever gaskets you want...it is your truck.
This is a subject like: What oil is best? Many opinions will surface.

 

[JoeSupra]

Re: lower intake gasket question

Short Story: YES.
Long Story and disclaimer....yes, as long as no one has changed the heads on your truck.
Only you know the answer. Read the posts above about checking the head part numbers located under the valve covers stamped in the metal of the head material. The only way to know for certain.

Bottom line...run whatever gaskets you want...it is your truck.
This is a subject like: What oil is best? Many opinions will surface.

I doubt the heads were changed on my truck. Truck is almost stock. But thank you guys. Hopefully people will see this and have a better understanding of this.

 

[SY-1193]

Re: lower intake gasket question

Just to add to this...
Those (pictured above) cover LB4's (stockers) and L35's. We didn't cover Vortec's so I will post pictures of them too. FELPRO 1203 also work for Brodix -8 and Brodix -10 heads also. NOTE: Vortec's and Brodix type heads require modification to the lower intake for the gaskets to cover the larger ports properly and apply pressure to the gasket tops. RACE SIZE PORTS

Notice it says the port size on the label. RACE PORTS.

I use these Felpro PN: 1203 on Vortec, Brodix heads and I put Hylomar Racing Formula from Permatex on the gaskets for extra holding. ( expensive sticky blue stuff - wear gloves - only used on 1203 gaskets).

.

If you are at this level you may have your own methods. I would also recommend at least a port match to the 1203 gaskets on the intake and heads if you are at this level you are looking for every bit of flow you can get.
Again...
Bottom line...run whatever gaskets/sealant you want...it is your truck.
This is a subject like: What oil is best? Many opinions will surface.

 

[Davemc1963]

Re: lower intake gasket question

I saw those magnum gaskets when I bought the Felpro 1202's. I had never heard of them, so I gave them a miss. Being that they have a tanged core, which I hadn't realised, I wish I had bought them now over the Felpro's which I have some reservations over, but so far so good. They look like a much better gasket imo. Although I found some OE GM ones after I changed them which is typical, they are probably worth as much as the truck.

 

[Don W.]

Re: lower intake gasket question

I discovered that when using the 1203's with Vortec heads they sit "low." Meaning if you let the little tab at each corner sit on the block like you would think it should the gasket is not centered over the intake ports. You have to move them up a little and plan on, obviously, bringing the RTV on the block up further.

 

[JoeSupra]

Re: lower intake gasket question

Sy 1193 I removed the metal blockoffs that these magnums come with like so..

Did I make a mistake? I figured it would be ok cause some of the other options we have dont have it blocked off.

 

[SY-1193]

Re: lower intake gasket question

Sy 1193 I removed the metal blockoffs that these magnums come with like so..

Did I make a mistake? I figured it would be ok cause some of the other options we have dont have it blocked off.

The metal block off holes go to the rear where the manifold water passeges are blocked off. When you put your lower intake on there is no where for the water to go for the rear holes. The block off plates stop the water from hitting the aluminum intake. I don't know why you didn't just use them as designed? Why waste your time? Unless you plan to put a cross over pipe plumbed in...which will be quite an undertaking with the distributor, map, fuel pressure regulator, fuel rail all in the way. Not to mention the wires there.

 

[JoeSupra]

Re: lower intake gasket question

The metal block off holes go to the rear where the manifold water passeges are blocked off. When you put your lower intake on there is no where for the water to go for the rear holes. The block off plates stop the water from hitting the aluminum intake. I don't know why you didn't just use them as designed? Why waste your time? Unless you plan to put a cross over pipe plumbed in...which will be quite an undertaking with the distributor, map, fuel pressure regulator, fuel rail all in the way. Not to mention the wires there.

I could of sworn I seen and read that some gaskets had to but cut open and not blocked off. Infact after looking at the discontinued Victor R gaskets they are open too not blocked off. So your saying Im screwed?

 

[SY-1193]

Re: lower intake gasket question

I could of sworn I seen and read that some gaksets had to but cut open and not blocked off. So I screwed up then is what your saying.

You can probably still use them. You did do a neat job cutting them out. It is just that I feel the metal adds strength to the gasket there as designed. You can probably use them as they are. I am sure you can feel the quality of the gaskets are way better than the paper ones. There is sealing lines around the ports regardless and it should seal just the same. Follow the directions for applying the rtv provided to the end tabs and the China wall of the block when you assemble it. You will see the way it was rtv'd when you take it apart also.

 

[JoeSupra]

Re: lower intake gasket question

You can probably still use them. You did do a neat job cutting them out. It is just that I feel the metal adds strength to the gasket there as designed. You can probably use them as they are. I am sure you can feel the quality of the gaskets are way better than the paper ones. There is sealing lines around the ports regardless and it should seal just the same. Follow the directions for applying the rtv provided to the end tabs and the China wall of the block when you assemble it. You will see the way it was rtv'd when you take it apart also.

No cutting involved I just popped em out of the port.I did dig into the gasket itself while getting one of em out but it didnt go beyond the raised sealing lines at all. I think its going to seal fine. Thanks for your input and giving me a slight heart attack. ahaha

 

[Couger1968]

Re: lower intake gasket question

They will be fine, a lot of the gaskets people are using have them open. I don't because I figured one less surface to seal.