I have the Dynomax/Walker 86110 Ceramic Full Length Headers, & Large oval port heads. I was going to use either SCE Copper Gasket 4013 or 4313, one is 1.875" Thick and the other is 2.00" thick, is there a big difference? I think the larger thickness is for flawed surfaces isnt it? Is there any special method to putting on the copper gaskets?

Phill, are you talking about the port opening size on the exhaust port. I think that a 2.00 in. thick head gasket is a little large. :D The quench wouldn't be too good and the compression would be a little low.
If you are talking about the exhaust port just measure the header opening and the exhaust port opening and see what you need.

Well they list the same number for thickness and diameter openings. The headers openings are just under 2" So the SCE 4013 would probably be the one? Which are 1.875"

Philo, I would go by the exhaust port opening on the head. You want the gasket big enough so there is no blockage but you need enough to seal properly also.

Dont overtighten the header bolts against the copper gaskets, the header flange will bend. Snug them up good, run the engine a few minutes and resnug, check/tighten again after breakin period, and after a couple of hours runtime and then a couple of more times in the first hundred miles or so, or untill they show no signs of working loose between checks/tightenings. headers tend to sink into the gaskets and settle as they go through several heat and cool cycles, copper or paper gaskets.

I'm still running the same cheap gaskets that came with my $79 headers I bought 2.5 years ago.
The key is to keep an eye on the bolts..keep tightening them every couple of days.I did that for about a 3 weeks straight,and haven't touched them since.

You ought to be able to get 2-3 years out of paper gaskets as long as you tighten them after 2-3 heat cycles,they won't come loose.

I'm running SCE copper gaskets and they work great. They will not blow out and you should never need another set of header gaskets. Make sure to mark the gaskets inside/out and left/right so that if you take them off at some point they can be put back in the same location using the same impression in the copper.

Same here....we use copper exhaust gaskets on all of our SBC and BBC turbo stuff. They work very well.