Head gaskets

[JimNolan]

Merry Christmas Guys,
    I decided to pull the 410 engine I have to fix the oil leak. While I've got it out I'm going to install a 268H cam in it and put thicker head gaskets on it. Edelbrock has a steel core laminate gasket that is .038 X 4.4. So does Fel-Pro and Mr. Gasket. Does it matter which one I use. Back when I first installed it they claimed a two layer steel gasket was the way to go with Aluminum heads and cast iron block. Well, now Edelbrock is touting their composite gaskets. Which one should I use or does it really matter. Thanks guys, Jim

[NIsaacs]

When I changed to the ED heads, I used the ED gasket #7337, it had Fel-Pro name and number stamped on it. I am a fan of Fel-Pro, Mr. Gasket...not so much.

Nick

[Lenz]

I'm running Fel-Pro head gaskets with my ED heads.  Torqued, walked away for an hour and re-torqued.  After break-in run torqued one more time, having no issues.  Got nothing against Mr. Gasket, just seems like some of their other stuff isn't top shelf and I never ran their gaskets at a critical assembly point like I have Fel-Pro.

[My427stang]

Jim why thicker head gaskets?

Potentially you can lose any benefit from quench that you'll gain from lower compression. Are they leaking, or is this a "while I am in there"

[JimNolan]

427Stang,
   By going with the 268H cam I'll increase my torque and horsepower (30lb/12hp) at 2000 rpm (where I usually cruise [gas mileage] ). The 30 hp I'll loose comes between 4000-5000 rpm(where I'm seldom at).
I'll raise my quench from .052 to .063. I'll gain 20 ci of useable motor while still maintaining a 7.6 DCR. And yes, you guessed it. I found antifreeze mixed in with the oil dripped on the floor from the back of the motor yesterday. I haven't got it torn down yet but I thought if I have to change head gaskets I wouldn't go back with the same kind and I thought I'd better ask you guys what you would recommend. You helped build this engine, what do you think. Jim

[My427stang]

I'd run a Felpro 1020.

Cheap-ish, easy and reliable.  .041 compressed thickness, never have to think about it again.

[jayb]

Jim, you might look at the new SCE head gaskets.  I saw them at the PRI show and they looked real good.  They are not for big motors (4.25" bore on the head gasket), but they have that raised silicone ridge around the water jacket and the oil transfer hole for better sealing.  They are also side specific; you get a left and a right.

[JimNolan]

Boy I feel little and small. There's a heavy stream of oil coming from between the transmission and the bell housing. I talked to Mike Forte and he's sending me the retainer seal and the membrane seal to fix it with. I couldn't find any oil or antifreeze coming from the heads or rear intake seal. Hopefully I'll have this oil leak fixed with just the transmission seal. I wondered why a rear main seal would go bad when I've done about six or eight of them and never had one leak before.

[jayb]

Leaks like that can be tricky; at least you found it!

[TomP]

Between tranny and bellhousing can be the rear cam plug or other oil passage plugs.

[cdcastle]

Hello- I'm new to the forum, but not new to engines- anyone else use Cometic custom made Head gaskets?  I am using them on my 427 SideOiler. They are pricey, but the guys at Cometic are very professional and I have had good luck with them and got exactly what I ordered and on time.

[jayb]

Welcome to the site.  I use Cometics on a lot of my engines, especially the higher horsepower ones.  They do indeed make an excellent head gasket.

[ScotiaFE]

I'll raise my quench from .052 to .063. I'll gain 20 ci of useable motor while still maintaining a 7.6 DCR. And yes, you guessed it. I found antifreeze mixed in with the oil dripped on the floor from the back of the motor yesterday. I haven't got it torn down yet but I thought if I have to change head gaskets I wouldn't go back with the same kind and I thought I'd better ask you guys what you would recommend. You helped build this engine, what do you think. Jim

Ideally you want .040" of quench. A quench of .063" will promote detonation especially at your relatively low rpm of 2000 rpm
and your use of low grade fuel.
Not sure where how you would gain 20 ci of motor from your plan.

[JimNolan]

Ideally you want .040" of quench. A quench of .063" will promote detonation especially at your relatively low rpm of 2000 rpm
and your use of low grade fuel.
Not sure where how you would gain 20 ci of motor from your plan.
[/quote]
I look at cubic inch as when the valves are closed and you're on the compression stroke.  Different cams give you different useable cubic inch displacement. My 410 probably has about 313 useable cubic inches.

[My427stang]

Jim, you are going to blow everyone's mind... 

Intake valve closing point adjusted displacement...it is indeed possible to calculate, but remember, depending on overlap, exhaust and other things that affect cylinder fill,  a "smaller" engine based on IVC may actually fill the cylinders more than a larger one, and it will likely be different at different RPM

Fun stuff to think about though