Ultra Gray or Ultra Black RTV

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68 Coronet RT

68 Coronet RT

68 GTS # 508 in Registry
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Getting ready to put my performer rpm intake on my stock heads. As per the instructions you cannot use cork gaskets on the ends. So my question is do I use the Ultra Black which is Maximum Oil Resistance or the Ultra Gray which is Maximum Torque gasket maker.
 
I prefer the Ultra Gray. It skins over quicker, and seems to work better especially on intake china rails etc. I learned this from the guys at Westech and Hot Rod magazine.
 
No matter what you use don't use so much as to make it fall into the valley and ultimately wind up in your oil pump screen.
 
I use ultra black and get it in a culk tube that way it’s easier to go across the China wall
 
JDPdart said:
I use ultra black and get it in a culk tube that way it’s easier to go across the China wall
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China wall or tRumps Mexico wall LOL. I called Edelbrock and talked to a Tech. He did say to use only the Ultra Black RTV as it's more oil resistance than the Ultra Gray
 
As a general rule they are color coded and easy to remember.

Red is for hot stuff.
Blue is for water.
Black is for oil.
Grey is for???

And the "Right Stuff" is for when you never want it to leak... (or come apart.)

:)
 
Permatex_Right_Stuff_Replica_01.jpg
I use the black Right Stuff on everything. The pan the pump the intake the transmission the main Seals Everything. Absolutely nothing has ever leaked "knock on wood!"
4 years of drag strip and danger rides....
I've had pretty much everything off and on also and trust me it doesn't come off easy but everything's doable.
 
I prefer the black for that application because it's more pliable and soft after it's cured, the grey I like more for high-pressure sealing like around water ports and thermostat housing because it gets really stiff when it cures.

FWIW I smeared a thick bead of Ultra Grey to seal the baffle I welded into my stock oil pan, 25k miles of being submerged in motor oil and there's been no degradation at all... I think it's safe to say the grey is plenty resistant to oil. I thought about redoing it before putting it on my next engine but that stuff still has no interest in coming off, it's stuck in there tight.
 
I use the 3M weather adhesive to glue it on the heads and I buy the big tubes of Ultra Black RTV from Advance Auto and apply it THINNLY to the intake side of the gasket.. I usually spend my points money to buy my Ultra Black.
 
Try Gray on one wall and Black on the other, then let us know which is better! I used Black per the directions and the many, many posts on the site!
 
pittsburghracer said:
I use the 3M weather adhesive to glue it on the heads and I buy the big tubes of Ultra Black RTV from Advance Auto and apply it THINNLY to the intake side of the gasket.. I usually spend my points money to buy my Ultra Black.
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China wall I lay the intake on DRY and take a black magic marker and trace where the intake sits. Then after I remove it I use my caulking gun with a tube of Ultra Black on it and lay down the bead needed. By checking it dry I get an idea how high of a bead I need then I lay a horizontal bead across the valley were the head and block meet.
 
Either will work fine. I like ultra grey because I use it pretty much everywhere and it's easier than stocking two different RTVs that do the same basic deal.
 
I prefer the black for that application because it's more pliable and soft after it's cured, the grey I like more for high-pressure sealing like around water ports and thermostat housing because it gets really stiff when it cures.

FWIW I smeared a thick bead of Ultra Grey to seal the baffle I welded into my stock oil pan, 25k miles of being submerged in motor oil and there's been no degradation at all... I think it's safe to say the grey is plenty resistant to oil. Permatex the Right Stuff Grey vs. Black I thought about redoing it before putting it on my next engine but that stuff still has no interest in coming off, it's stuck in there tight.
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I understand your preference for using black sealant for certain applications due to its pliability and softness after curing. It can indeed be advantageous in scenarios where flexibility is desired. On the other hand, you mentioned that you prefer grey sealant for high-pressure sealing, such as around water ports and thermostat housing, because it becomes stiff after curing.


Regarding your experience with Ultra Grey sealant, it's great to hear that it has performed well in sealing the baffle in your oil pan. The fact that it has remained intact and resistant to degradation even after being submerged in motor oil for 25,000 miles is a testament to its durability. It seems that the grey sealant has proven itself to be reliable and oil-resistant in this particular application.
 
Old thread but if you really want something that works, get the Ford grey RTV and use it all over the intake gaskets and on the china walls. Once cured, you can take the intake bolts out and throw them away and the next time you have to remove the intake, it will break off in pieces.
 
I use the copper because I have a bunch of it, and it works well. I let it cure for a couple days then take a utility knife and trim along the intake.
 
I use black RTV Max oil resistant on the intake ends (china wall). I love Ultra Grey, but usually on freeze plugs, or T-stat gasket, and such.
 
318willrun said:
I use black RTV Max oil resistant on the intake ends (china wall). I love Ultra Grey, but usually on freeze plugs, or T-stat gasket, and such.
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I've had to literally chisel off the oil pan on a Ford 2.9L V6 that was factory installed with the grey Ford RTV. We tried everything. Carb cleaner, brake cleaner, I even tried the smallest wound guitar string I had. I had to go back and GRIND the remaining pieces of oil pan rail off the block with an angle grinder. I've never seen anything like it. That pan would have never leaked had we just taken all the bolts out. It was ridiculous.
 
j par said:
View attachment 1715273872 I use the black Right Stuff on everything. The pan the pump the intake the transmission the main Seals Everything. Absolutely nothing has ever leaked "knock on wood!"
4 years of drag strip and danger rides....
I've had pretty much everything off and on also and trust me it doesn't come off easy but everything's doable.
Click to expand...
Nothing leaks with Right Stuff, but it takes an air-chisel to take it apart.
I just use the Black RTV, it seals, and will come back apart fairly easy.
 
Right Stuff and 3M Weatherstrip Adhesive, ( I prefer black )
Everything else went into the trash years ago.
No regrets .

I've found regular RTV of any color may cause more leaks than it solves. Especially if you are one to go around "snugging" pan bolts.

It's not nec to chug on a great bead of Right Stuff, as you are used to with reg RTV, a small bead sufficient to fill the void, bonds really well on clean surfaces.
No air chisel nec, lol

Good luck .
 
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