What's a good sealer/ gasket for exaust to engine . looks like some kind of grey sealer was used from factory. berrilli 26-ssr.

Permatex Ultra Copper silicone gasket maker. Almost any automotive parts store will have it. Don't use a gasket, just the silicone.

I second that!!!!

I would just add to that to be sure the mating surfaces are clean and flat before assembly. I usually clean the mating surfaces with something like acetone before applying the sealer. You only need a very light coat of sealer. Gaskets just go to pieces over time and allow the muffler to loosen.

I think you'll find he used JB Weld to make the gasket and to lock the bolts in. After I got my Brillelli I started using it too, works great.

alert 5,

I use Permatex High-Temp RTV Silicone Gasket Maker. I have not had anything come loose using this yet.

Same here. RTV silicone sealant , applied very thin on clean and planed surfaces, let dry, then assemble.

Yup...permatex ultra copper here. The gaskets are good to hold onto, they make nice templates for making header flanges later on

Perfectly flat surfaces are not necessarily the best for attaching mufflers. The area between the bolts can flex and warp. A slight convex in one of the surfaces will help keep the bond pressed tighter. Reducing the chance of vibration and movement. I file and sand my headers a tiny bit round. Helps the bolts to stay tight too.