Are heat risers found on 68 Camaro,s w/SS option & 350 engines?

Answer 1

It depends on the engine options. ...and what you mean by heat riser? Chevy engines of that era had what is called a heat riser valve which is located between the exhaust manifold and front exhaust pipe. It has a thermostatic spring which closes the valve at cold engine temps which forces some of the exhaust gases back through passages in the intake manifold under the carb area to help warm up the choke coil. So that heat riser valve was found on all models/engines with a heat operated choke setup vs an electric choke coil setup.

Some engines also had what is called a heated air pipe which is a short piece of metal tubing that goes between the heat stove on the exhaust manifold and the air cleaner on most models used to help in cold weather conditions to prevent carb icing and aid in low temperature engine operation. Most models had that setup except for some high performance V8 models of Camaros, Chevelles, Corvettes, etc.. that had open element air cleaners and no snorkel.

https://www.hemmings.com/magazine/hmn/20...

Answer 2

Yes, they are. A "Heat Riser" is a metal tube that runs from the top of the exhaust manifold to the air filter box. The purpose is to provide heated air to the carburetor on cold days to reduce carburetor icing. It lets your engine run smoother while warming up to full operating temperature. Heat risers are no longer common because MOST newer cars have fuel injection instead of carburetors.