I was told by a well known engine builder to use RTV instead of an exhuast gasket. I just wondered if anybody has done this and what type of RTV was used (copper,high temp. black, etc.)? Any help would be greatly appreciated.
I've heard of this for old cast iron manifold because ideally both the head surface and the exhaust manifold are flat.
Also I remember watching one of the ESPN car shows and there was some header manufacturer that actually recommended RTV. But again the header had a wide weld bead on the engine side of the header flange that had been milled flat.
You can use copper RTV. I've done it. It's a mess to clean later. You can also order copper header gaskets for $20 to $30 and keep reusing them. That's what I do now. If you get a leak pull the header, clean the gasket with brake clean, carb cleaner or my favorite a can of heavy duty oven cleaner (from the dollar store and put it back together.
Dragstang has a good comment for people with leaky headers. My friend races roundy-round cars and we soak standard header gaskets in water and it works great. It has always seemed to work better when you install the gaskets and fire up the engine and let it warm up to operating temp. and shut it off and let it cool. Tight seal and no leaks!!
I have used the "red" high temp silicone for a long time, I smear a thin coat on the head and header side and bolt up the header, works for me, never tried the copper though..or the water soaking...I may give those two options a try...
I dont like the mess of using rtv, its hard to get the headers to line up perfectly without smudging the stuff all over the place. IT would probably work better with header studs though. I soak my gaskets and I've never had a problem.
A forum community dedicated to Ford Mustang owners and enthusiasts. Come join the discussion about performance, production numbers, VIN decoders, modifications, troubleshooting, power adders, DIY tutorials, and more!