re: that heat riser. Here is what it looks like. It's part of the exhaust manifold it's not separate
Some food for thought. The above is from a 46K mile 69 Supreme. heat riser valve is present. I have a 62K mile 69 S and there is no heat riser valve in the exhaust manifold. Best I can tell, both engines have their original exhaust manifolds and haven't been messed with, so heater riser or no heat riser. Your call. Another item to think about. Run the heat riser and break out the sawzall to cut out the butterfly.
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1969 Cutlass S W-31 - 13.86@100 TnT US41 2009
1970 Tempest GT-37 400ci 4bbl 4sp -
[email protected] PSMCDR 2011
1970 F-85 - daily driver or clock it with a sun dial
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