Tweet
I need answers to two questions in regards to the exhaust manifolds on my 1965 coupe, 327/350hp. My exhaust manifolds are numbered correctly, but they have been painted silver in color. I assume the exhaust manifolds should be painted chevrolet orange like the engine block. Also, they have gaskets installed between the manifold and head surface. Should they be painted chevrolet orange and should I remove the gaskets for flight judging?
-
-
Re: 327/350hp Exhaust Manifolds
No gaskets. They should be cast color with some chev orange over spray on them. -
Re: 327/350hp Exhaust Manifolds
Actually, paint coverage on the manifolds was pretty complete at the time the engine was built, but most of it burned off between roll test and the dealership delivery. Take out the gaskets, paint like you were in a hurry to cover everything, and once you have run the engine for a few minutes you will be perfect, assuming you remove the silver paint first. Note the heat riser was not installed until St Louis, so it shoud remain unpainted.Bill Clupper #618Comment
-
Re: 327/350hp Exhaust Manifolds
No Gaskets? I have never heard of that, were they just bolted on metal to metal?Comment
-
Re: 327/350hp Exhaust Manifolds
Exactly. Metal to metal. All the judging manuals spell that out, so it is not a well-kept secret.Comment
-
Re: 327/350hp Exhaust Manifolds
Chevrolet NEVER used exhaust manifold gaskets on SB or BB V-8's, although all the gasket set manufacturers feel compelled to include them in their gasket kits.Comment
-
Re: 327/350hp Exhaust Manifolds
I use a thin film of orange High Temp RTV.Comment
-
As Terry suggests in a later post, you
might be well-advised to "skimp" on the paint coverage amount on the manifolds; I suspect that what is now available as paint just "may" exceed what the General was paying for in the '50's and '60's....Comment
-
Re: 327/350hp Exhaust Manifolds
When you remove the gaskets check the manifolds carefully for flatness. The gaskets can compensate for slight warpage, but to seal well without gaskets requires very flat surfaces.
I recently learned this lesson first hand after I removed the gaskets for judging. One manifold had a very audible leak and I had to remove it again and true it up. On that manifold, the large center portion that connects to cylinders 4 & 6 was slightly concave, with the middle being about .015 inches lower than the two outer edges. So, the bolts could be torqued up to spec and there would still be a leak.
I used a flat file, a straight edge, and about two hours of sweaty work to fix the problem. Later, a friend said he had accomplished the same task by cutting a belt sander belt and taping it to a known-flat surface so that he could true all three surfaces at once. Even so, he said it was a slow, messy job.Comment
-
Re: 327/350hp Exhaust Manifolds
Thanks, good advice. I will check the mating surfaces before I re-install them.Comment
Comment