Head gaskets

[fekbmax]

How much compression are 1020's good for ?
What's the thought on useing copper coat?
How many uses do you guys normaly get out f a set of Cosmetic's ?

[fryedaddy]

1020s-10.1?

[Barry_R]

we install them dry on extremely clean and flat surfaces.  Have run them at 13:1 and 700+ horsepower without a problem, but with evidence of stress after teardown at that level.  Probably at the design limits...

[Joe-JDC]

I am going to go out on a limb here, but my engine was close to 12:5 to 1, 427 +.030, 3.98" stroke, and C5 Medium riser heads with tunnel wedge, big solid lifter camshaft, and it lived many a race at 7400 rpms through the lights.  Mechanical tach drive, so it was not guessing the rpms.  I think the problem today with many builds is that the aluminum will bed the fire ring after a few heat cycles, and the heads should be re-torqued in proper sequence, one bolt at the time.  Most of the aluminum heads for the FE only have a .500 or .600 firedeck, and if you cut the heads .040, .050, or more, the hardness is weaker, and the heads bed in making the torque relax some.  JMO, but that is my experience.  Especially with SBF aluminum heads.  Joe-JDC

[ToddK]

I don't mean to hijack this thread, but it is related.

Robert Pond recommends using the 1020's on his aluminium block, however I would prefer to use Cometic's. This is going on a 14 to 1 comp race engine. Surely the Cometic would be a better option in this case? Any reason the 1020's would be preferred head gasket?

[Joe-JDC]

If your liners have taken a set, or been torqued down for honing, or had the block decked, then the cometics should work.  Some aluminum blocks don't have the smooth deck surface necessary for the cometics from the mfg.  If the liners never had a torque plate installed or the engine ran through heat cycles, and the liners were milled flat when new, then the block will grow the first time it is run, and the engine will grow more than the liners, and possibly have a water leak.  Gaskets come into play as to where the crush bead is located on the top of the liners to stop water leaks.  I would call Pond and ask for specifics, or e-mail him.  Joe-JDC

[blykins]

I have ran 1020's with 12.5:1 with over 700 hp. 

A couple of notes on Robert's block (or any aluminum block):

*The sleeves must be set*!!! before any machine work starts.  We usually bolt torque plates on the block and put it in an oven.  Robert will tell you that he prefers Felpro 1020's because in the event that a sleeve drops, the fire ring matches the sleeve and will take up the slack.  Robert uses 1020's on his wedge headed engines, but will use Cometic gaskets on his Cammers.  I have used Cometics on Pond aluminum blocks without issue, but the sleeves absolutely have to be set. 

I use Hylomar spray on the Cometic gaskets and have used copper coat on gaskets that had been used once/twice.

[ToddK]

Sleeves have DEFINITELY been set on my block, so we'll go with the Cometics.