Intake Manifold Gasket

[D.A. Davis]

Can anyone give some information on an intake gasket for a AMC 360 that is a non-metal gasket without the valleypan made on it? I remember reading somewhere about a replacement gasket for the old metal one.

[porkchop]

Yes I have put them on my wag. Go to www.mrgasket.com (http://www.mrgasket.com) and do a search you will find them. There are two different ones. I like the results I have from them. They block off the cross over so cold starts will be a little rougher but over oll performance is great.

[porkchop]

Ok I found them at Summit Racing (http://store.summitracing.com/default.asp?target=search.asp%3FType%3Dbykeyword%2 6Part%3Dintake%20gasket%26Search.x%3D1%26SearchTyp e%3DBoth) Here is what they look like.

http://store.summitracing.com/global/images/prod/large/mrg-800.jpg

[ September 20, 2002, 03:31 PM: Message edited by: porkchop ]

[Jambo1]

I got a Felpro valley pan from a friend for free. It's the big metal pan with the rubber strips.

When I do my rebuild, is this pan o.k. or should I get something better? As it is now, I got a pool of oil right behind my distributor which I think is coming from the intake. I dont want this to repeat. There is a sea of gaskets makers out there. Will the Felpro suffice? :( Im not doing any high perf stuff by the way.

[Stuka]

Yes, you REALLY need to use the valley pan...do NOT use the little gasket, you will run into problems. Also, you need to use the heat shield off the OEM manifold, without it you will be getting a TON of oil into the PCV vavle.

[porkchop]

Originally posted by Stuka:
Yes, you REALLY need to use the valley pan...do NOT use the little gasket, you will run into problems.NO you do not need the valley pan gasket, and yes the little gasket is better for sealing the intake, especially if you have an aftermarket intake and milled heads. As long as you use the heat sheild on the bottom of the intake you are fine. I have had it on for sometime and have never had a problem. No high heat, blow by or nothing. There is someone else on the board, can't remember the name, that has run nothing but the non-valley gaskets for about 10 years and has never had a problem.

[Stuka]

oh the engine will still run fine without the valley pan...it will also run with only 7 pistons ;p Doesnt mean its right...

[ September 20, 2002, 07:48 PM: Message edited by: Stuka ]

[Frankenstien]

The metal pan is your best option and they work great. They also have inset holes that punch down into the block to hold it in place while mounting. And what ever you do dont use the gaskets in the front and rear of the manifold , use a thick layer of Black RTV. These little black gaskets will blow right out at the first hint of a backfire.

J
Just did mine.

[Stuka]

frankenstein: if the rubber gaskets are done correctly they will never leak (none of the ones i have done have leaked..just clean metal/rubber with enamle reducer to get rid of all oils..and it will adhear with the metal)

on a second note...how is a backfire gona blow the rubber gaskets out...you should NOT bet getting pressure in the lifter valley from the cylinders..if you do...something is very wrong...

[porkchop]

Originally posted by Stuka:
oh the engine will still run fine without the valley pan...it will also run with only 7 pistons ;p Doesnt mean its right...Just curious, what is wrong with it? Please enlighten us.

[gwinn]

I need to know ASAP exactly what will happen if the valley pan gasket is left out. The engine is being reassembled as I'm writing this. I was convinced to leave it out by the engine shop. He said I wouldn't need it as long as I changed oil every 3,000 miles. He's also running an extra line to get the oil to the #7 & 8 journals. I really didn't understand most of what he said or why it should be done. I have confidence in his advice since he builds mostly engines for ASCA sprint cars. My GW isn't a sprint car, but he has rebuilt some 360's and 401's. They were for stock cars back in the dark ages. Is there a good reason why this pan gasket needs to be installed. Explain in detail, please.

[Stuka]

The valley pann helps prevent carbon build up in the lifter vallley by keeping the oil from burning on the bottom of the intake. It also helps keep the oil down by the lifters rather then splashing around. And the engine builder was correct by saying regular oil changes kinda negate the reason for it. But my oil gets dirty fast from offroading (dont ask me how but it does) so I was not gona take a chance. My engine had one tiny spot of carbon build up (about the size of a marble) when I opened it up after 162k miles. So I say the valley pan did its job well. I feel it was well worth the few extra bucks to put it together correctly. It also acts as another barrier to keep oil out of the pcv (my pcv is clean inside...zero oil)

So to each his own I spose...but I put it in and when i rebuild it next year it will get another.

[Jeep Jeep]

To add a little here. On my first rebuild, I installed a used Torker Manifold with gaskets that PC has shown. I have had no problems with it, but I have not torn it apart yet. I also change the oil every 3000 miles. I just completed the 401 build up. I bought a new Performer with EGR and the instructions from Edelbrock, states to use the valley pan with there intake. Stuka makes a good point about keeping the oil of the bottom of the intake. I had purchase a set of gaskets until I read the insrtuctions on the new intake. Just as a side note. My heads were resurfaced and so far everything is working just fine.

[oddfire]

It sounds like you have a very competant engine builder if he's doing the oil line mods. Most rebuilders don't even know of this little trick.
I think also with the oil lines run from the front of the lifter valley to the rear, there may not be enough room under the intake manifold for a metal valley pan...........phil

[Chero77]

I don't have any personal experience with this, but on the AMC forum, most of the guys that run without a valley pan complain about oil getting sucked into the PCV. Seems like they either go back to a valley pan or seal off the PCV hole and get valve covers with holes for breathers.

[porkchop]

Well I have never had a problem with the oil getting into my pcv. There is a hole on the valley pan gasket directly below the PCV, why is it there? I also called Edelbrock to ask them why you need the valley with their intakes they said you don't. They have had that in the instructions for a long time and have never bothered to take it out. If the heads are resurfaced then a valley will not seal right unless you have the intake done to match and then it still might not seal right.

As for the oil not getting to the lifters. How is that possible? The bottom of the intake does the same job as the valley pan gasket. If you don't put on the heat sheild/oil deflector on the bottom of the intake then I can see a problem occuring. I pulled apart my old engine that had a valley pan in it to put in the new cam. There was so much burnt oil under the PCV it looked like coal.

I ask about three engine rebuilders if it was needed and they all said NO. That is all they do rebuild engines. One of them has been doing it for over 40 years. I have a tendency to believe those that have knowledge in that area not the shadetree mechs. I am strange like that. So bottom line is do what you want to YOUR engine. But before you do get a good engine rebuilder or someone that actually does this type of work, to tell you what is right, like gwinn did, not the kid next door.

[jeepjake]

OK, thought I'd have to throw in here.

First time I rebuilt a 401 in my '74 was in 1987, I used the stock valley pan (Fel Pro). It leaked like a sieve.

Took the manifold and heads back off, had a machine shop square up and clean the mating surfaces. Used the factory pan again, the next time with the goop that Victor packages with theirs. It was better, but still leaked (vacuum and oil).

Finally talked to a guy who worked on AMC's at a dealer sometime in the early 90's (where I eventually acquired a job as an engine mech for a short time) and he ordered the Mr. Gasket comp gaskets (like the pic that's posted). Installed that and no leaks anywhere.

This engine was torn down after 140k on it and another build, this time bored to .030 over (yes, we mapped the cyls), line bored crank journals, decked, etc. At teardown, the underside of the stock 4bbl manifold was perfect, no oil or carbon buildup, no crud, nothing (I did paint the underside of the manifold inc the riveted on shield with engine paint when I assy'd).

Put another 238k miles on it when I finally parted it out and there was STILL no crud buildup on the underside (sold the manifold on ebay).

Also, I've never had a problem with oil coming up through the PCV in the 15 or so years I've used comp gaskets.

Through the years there has been 3 401's and half a dozen or 360's I've used the comp gaskets on and wouldn't go back to that stupid valley pan for anything.

One thing I do now is use the Ultra black around the port holes and goop up where the manifold meets the head and block, and cut out holes for the exhaust feedthrough and goop around them.

Also, I use a "little" ultra black on the rubber gaskets and let it almost dry before assy'ing (they'll just slip right out like hot snot if you don't let them dry enough.)

Have tried just using a bead of sealant instead of the rubbers, but with the close to 1/4" gap, I always had to redo them.

The biggest thing with carbon or oil burning under the manifold is using Quaker State (std oil) or Pennzoil. Use a synth or a southern base oil and it won't crud up.

[Jeep Jeep]

Hey, I just followed the instructions from Edelbrock on the intake install. I just went out and read the instructions again and there it is.

(CAUTION) Do not use high performance or competion type intake gaskets for street applications. Due to material deterioration under street conditions, internal leakage of both vacum and oil may apply.
Use only Fel-Pro#MS96011 or OEM steel shim intake manifold gasket for this installation.

Now if Edelbrock states that it is not required. Maybe they need to have new QA department. When it is listed as a CAUTION, one would tend heed to it, or maybe it is just my 19 years of military Avaition Maintenance experience.

Like

[Jeep Jeep]

Well sense I just Fat-Fingered my last post, I will finsh.

Like I said before. I have done both. I just wanted to shed light on what the instructions stated from Edelbrock. The engine builder that did all my machine work also recomended the Valley pan. Now if it leeks, what can I say, I followed the instructions. So far it has not. I will say this. I doubt vary seriously that the factory intake and heads where match from the factory. Just a thought.

In the Edelbrock instructions it also states to apply Gasgacinch to both sides of manifold as well as head surfaces and also to apply a bead of RTV around water ports and coat base bolt threads.

I don't claim to be a Shadetree machanic. I was just trying to shed light on my experience. But if you think about it, aren't we all, to some degree Shadetree machanics

[porkchop]

When it is listed as a CAUTION, one would tend heed to it, or maybe it is just my 19 years of military Avaition Maintenance experience.Then you should know about revisions and IRACs. I have been in military aviation long enough (10 years) to know that when there is something that just ain't right to you or that you don't understand you call the tech rep to be sure. I did, I called edelbrock and talked to two different people and they both told me that the valley pan is not needed.

[Jeep Jeep]

Then you should know about revisions and IRACs.

Yes I know. PC I appreciate the phone calls to Edelbrock, but did they say not to use the valley pan? If so then it's time for a TPDR. I did not question the installation because it did seem right. Like I said before, I intended to use gaskets until I read the instructions. The TECH manual states the valley pan seals the heads to the block and also serves as an oil splash baffle.
I too will call Edelbrock and complain that they need to clairify this issue.