Recommendations for Hemi intake gaskets and intake stud kit

[AR67GTX]

In another thread I’ve narrowed my largest oil leak down (I think) to the rear china wall gasket pushing and bulging out from under the manifold. It will be interesting to get it off and find out how this happened as there are 3 dowels across the area that should pin the gasket in place.

I’m looking for the best gaskets to go back with and also a black finish stud and nut kit. The bolts I have now are 4.5mm hex socket bolts that I’m leaning against reusing as I think studs and nuts might be better since retorquing seems to be commonly necessary for the intakes on these engines.

I‘ve read of one recommendation for Superformance gaskets for the intake. I know nothing about them.

Thanks

 

[pnora]

I used the FelPro FEL-1234 and used silicone on the front and rear.

 

[snakeoil24]

Super performance has become a leader ive used a few of their pieces. Bolt kit can be ordered from Dodge Boys on Ebay and your advised to drill for safety wire considering your torque range is 70 inch pounds.

 

[Beekeeper]

Superformance gaskets are excellent and I would consider doing away with the China rail gaskets and go ultra grey rtv instead.

 

[68 HEMI GTS]

I just used flat out gaskets on mine. Glued to the heads with weatherstrip adhesive. I vasolined the intake side. RTV always on China walls.

 

[gtx6970]

Anyone ever stippled the head to give it some teeth for the gasket to stay in place.

Ive been told its a common thing for the street hemi to suck an intake gasket in causing it to use oil

Ive also been told to leave out the end gaskets and go with a large damn of RTV .
But have not tried any of this myself.

But plan to do some some work on mine this spring and I think I want to pull the intake and ck for my oil consumption .
Plus need to go thru the valves

 

[AR67GTX]

I would think the 3 dowels across the ends would keep the gasket in place although a little something to tack it would probably be good. However, I appear to have a fail for some reason. I don’t think you will find the end pieces getting sucked in as generally the crankcase is not going to have a vacuum unless one heck of a lower gasket leak around the intakes that overpowers any blow by. I worry more about having too much + pressure in the crankcase from a worn engine but I don’t think that’s the case with this one. Maybe they were talking about sucking in a piece of gasket sealing the intake passage. I also haven’t done the RTV dam before and I’m a little reluctant for fear of screwing it up. I’ll think about it some.

 

[pnora]

Anyone ever stippled the head to give it some teeth for the gasket to stay in place.

Ive been told its a common thing for the street hemi to suck an intake gasket in causing it to use oil

Ive also been told to leave out the end gaskets and go with a large damn of RTV .
But have not tried any of this myself.

But plan to do some some work on mine this spring and I think I want to pull the intake and ck for my oil consumption .
Plus need to go thru the valves

I think thats why they like to glue the gaskets to the head. That seems to work very well. The large dam of RTV also seems to do the trick. On my block and intake surface I used an engraver and made lines that the RTV will grip to. I also use guide studs so the intake drops straight down on to the RTV. Clean and properly machine fit is a must. Torque and retorque after each drive when cold the next day. It will take 5 to 10 re-torques before the bolts quit moving. Re-torque is critical.

 

[gtx6970]

I would think the 3 dowels across the ends would keep the gasket in place although a little something to tack it would probably be good. However, I appear to have a fail for some reason. I don’t think you will find the end pieces getting sucked in as generally the crankcase is not going to have a vacuum unless one heck of a lower gasket leak around the intakes that overpowers any blow by. I worry more about having too much + pressure in the crankcase from a worn engine but I don’t think that’s the case with this one. Maybe they were talking about sucking in a piece of gasket sealing the intake passage. I also haven’t done the RTV dam before and I’m a little reluctant for fear of screwing it up. I’ll think about it some.

My reference was in regards to the intake to head gasket.
Ive heard and read it somewhat common to suck the lower edge of the gasket into the valley pan / lifter area causing a vacuum leak and or oil consumption issue

But I agree, one would think the 3 dowels would be enough to hold the end seals in place

 

[pnora]

I would think the 3 dowels across the ends would keep the gasket in place although a little something to tack it would probably be good. However, I appear to have a fail for some reason. I don’t think you will find the end pieces getting sucked in as generally the crankcase is not going to have a vacuum unless one heck of a lower gasket leak around the intakes that overpowers any blow by. I worry more about having too much + pressure in the crankcase from a worn engine but I don’t think that’s the case with this one. Maybe they were talking about sucking in a piece of gasket sealing the intake passage. I also haven’t done the RTV dam before and I’m a little reluctant for fear of screwing it up. I’ll think about it some.

Once you get it apart you may see why they failed. My experience is unintentional installer error. Use guide studs.

 

[6PKRTSE]

I use Cometic gaskets. Almost everything is studded on my engine. Main studs and side studs, head studs, front cover, oil pan, water pump with front plate, intake, valve covers, headers all in stainless etc. All from ARP. Some are kits from ARP, other sizes I gave ARP all my sizes and they shipped me what I needed.

 

[dvw]

Just run the gaskets on the heads. Clean the china wall and lower intake well. Use Ultra grey and you'll never have another issue. Interesting fact I learned about RTV years ago. How do you know your surface is clean enough? Wipe a very thin layer on the mating sufrface with your finger. It should stick and spread smotthly. If if rolls off and fails to adhere, it's not clean. If you do this on all the mating surfaces, the bond will be permanent. Then lay a nice bead. If you let it dry a day you can trim the excess and you can't even see it. Hell you can use Ultra grey on an oil pan. Take the bolts out. It wouldn't come off. The lid, valley tray, water pump, mootor plate are all Ultra grey only. The pan gets a gasket. Why? So you can get it off. The gasket will tear during removal. Without the gasket good luck.
Doug

 

[Runcharger]

In 42 years I've never sucked in an intake gasket. I use RTV on the China walls as well. And retorque until it stops needing it.

 

[AR67GTX]

So I see the Superformance intake gaskets are available in .062” and .032” thickness. I’m thinking what appears to be a stock street Hemi uses the .062” ones based on the Fel-Pro set?

Maybe I can find a place on my intake to try to get a measurement of the assembled gap with some feeler gages

 

[pnora]

So I see the Superformance intake gaskets are available in .062” and .032” thickness. I’m thinking what appears to be a stock street Hemi uses the .062” ones based on the Fel-Pro set?

Maybe I can find a place on my intake to try to get a measurement of the assembled gap with some feeler gages

Once you get the intake off you will be able to see the sealing of the gasket. If good measure the thickness.

 

[AR67GTX]

Looking at the compressed gasket on the heads and holding feeler gages to it it looks to be a little over .060” thick on the intake surface. Hope I don’t have to go to the .120” inch gaskets. I’ll start taking it apart and see what it looks like. I don’t think the intakes have been sucking oil as the plugs are dry and no smoke.

I wonder what OE Mopar gasket thickness was used on the intake?

Also, I was mistaken on the cap bolts taking a 4.5 mm hex head. After working the paint off one a 3/16 “ hex head seemed to fit fine. They obviously haven’t been re- torqued after the engine was painted so it will be interesting to pull the intake off.