Hello,

my headgasket's are leaking now (felpro 1094, 0.015" copper, coatet with copper spray) and they need to be replaced this winter. I need some help with choosing a headgasket. The heads will be ported in the next time too. I'm installing a supercharger 06/07 (centrifugal) and need to know what a good headgasket is for that use. Compression should be around 8.0-8.5:1.
It's a 305 with 64cc Pro Topline Vortec's, 650 Holley DP, Powermax 2031 208°/214° (etc, see sig).

Any suggestions? (no, i'm not going for a 350. i just hope that the internals hold more than one season )

Nebu.

Edit: can someone put this in the power adder section? thx!

 

what is the piston CC. Do you have 8 to 8.5:1 now with the 64cc heads. Must have big dish pistons in there. Who makes them??

 

I was using the Cometic Multi-Layer steel ones for mine. (15#'s) They held up very well. I believe theres a calculator on "Ross Pistons" website that lets you play with head gasket thickness, cc, etc to calculate your final static compression.

 

I'm around 9:1 now with the .015" headgasket. I think ~ 8:1 should be ok with a supercharger, is it? Can't really do a perfect compression calculation because i don't know the deck height and the valve pocket cc's. The internals are all stock (lo3) with 68k miles on the clock.

Vortec Heads with Valve pockets, 4.080 bore, #C5474-040. is this the right one? The gasket thickness is .040"?
What do you think how much hp do the internals hold up?

Nebu.

 

I run SCE copper head gaskests with an o-ringed block. Three years now, no leaks. 0.060 thickness

 

Thats perfect. You should have no detonation problems and be able to run lots of boost assuming your motor can take it.

 

When using the small bore gaskets you have to make sure they clear the chamber. They hung over just slightly on my vortec heads in one spot.

Since you have stock internals, 6-7 psi is probably a safe number for the pistons. Which means any of the gaskets with a wire fire ring insert will work fine. There are 350's running 12-15psi with the felpro 1003. I think the cometic is over kill for your setup and I'd check into using them on a used motor. I think they supposed to be run on a fresh block/heads.

 

what about these. they say its for some vortec engines. stock bore is 3.740". the gaskets got 4.080". so i assume it should fit? how much hp do you think i'll gain from the sc?

nebu.

 

Chamber- not cylinder bore.

Those are the gaskets I tried to use.
They may or may not clear the chamber

8lbs boost, maybe 1.4x stock.

 

Get the cometic head gaskets and be done with it. I'd get some copper seal spray and give them a good coat before your put them on.

 

i did that to my felpro 1094 and they are leaking... both... so i dont think that i'll be using it on the new gaskets.

maybe i'm getting
these. they have the same bore as my old ones and they cleared the chamber from the vortecs. as for the cometic's, haven't found a dealer yet that sends to germany.

 

Check the links page on my site.
The engine builder link will ship international.

 

SCE makes a gasket now that is copper, and print-o-seal style, people have been loving them for awhile now.....as they dont need o-ringing

preston smith (here we go again) has been using them for some time now in his 9sec turbo iroc and swears by them.

im gonna be using them on my car this spring as well

 

Why wont FelPro stock replacements work? I have had no problem with Fel Pro 9441PT's in my buick V6 and it only has 4 bolts per cyl verses the SBC's 5 bolts. I just pulled my heads off to get some more porting and guides done and the gaskets look like new even after 200 passes this year with boost between 18-26psi(depending on gas) and a best ET of 10.77 @ 125.3 at almost 3700lbs raceweight.

I just think with a good tune that stock replacement felpro's should work fine.

Steve

 

its a luck/durability issue......MOST of the time, with heavy boost stock type gaskets don't last......especially with alot of hard driving when the cylinder pressure really gets up there.

sometimes you get lucky though, and for some reason the head has a perfectly even clamp load on the gasket, it'll stay there forever

 

Bore size is different too. And area is a square function.
Double the radius is 4x the area.
Not to mention deck thickness etc. Can't compare buick to chevy. To many variables.

 

I suppose there are too many variables, and I'm sure luck has something to do with it. I just figured I'd post my experiences with felpro. On another note when a turbobuick blows a gasket it is usually due to a tuning problem regardless of gasket used.

Steve

 

Do not use copper spray, aluminum paint or any othe coating on the head gaskets. Install they clean and dry on a clean dry block. (clean the surfaces with spray brake parts cleaner) Any spray stuff on the gasket just acts as a lubricant allowing the gasket to slide on the head under boost and detonation making it that much easier for it to blow out. ya want the gasket to have good traction with the head and block surface. Copper spray (or any other sealant) on a head gasket is just like haveing grease on the bottom of your shoe.

 

First pick was Cometic, second choice would be SCE.

 

we used to be sponsored by cometic.....i was never really impressed with their gaskets

 

Can anyone tell me the name and who makes this product "copper seal spray" if they do what i'am thinking I wouldn't mind coating my paper intake gaskets with them.

 

if they're talking about what i think they're talking about, its normally used on solid copper head gaskets.....we use it on the truck

 

i used something similar to this.. maybe this is what your searching for.

 

MLS gaskets, installed dry.

i mean, sure, you have dozens of other options but thats just what the:
LS1,honda,DSM,toyota,ford,BMW, Holden, Mazda, Mitsubishi, Nissan, Saab, Subaru, Toyota, Volkswagen, ect ... guys use... and some of them, esp the smaller motors, push ALOT of boost and see cyl pressures higher then you'll ever see.


and they're still daily driven and expected to last 1000s of miles.

not to mention, multi-layer-steel gaskets are stock on almost every new performance motor.. they work.
if they dont work for you, you're doing something wrong.. lol.

 

different types of head gaskets exist for a reason

 

yea, they made alot of kinds before they came out with MLS.


lol, seriously though, its not the only one out there, but its the only one to my knowlege thats doing OEM life to cars pushing crazy boost.. im sure theres some other composite gaskets that are doing that...
the newer graphite ones seem to hold up great to a point.. if you never exceed that point, they dont really give...

 

my point is that there are parts intended for different applications, and no single part is the beat-all end-all answer for every situation.

theres a reason we use straight copper gaskets on the blown-methanol 482.....that has alot higher cylinder pressure than anything you're talking about.