I have fired up my '73 250 with Langdon's cast headers, Offy intake and Holly 390. After some tuning it is running ok but I have 2 issues to address. One is water seeping from the Langdon's Heat plate around the gasket. It is scary tight and I was careful to get it tightened down even but it still seeps. I used the stock gasket used to seal the exhaust heated manifold and I think is not suitable for H20 use maybe?
The 2nd problem is a weird one. All the time the engine is running it emits this piercing incredibly loud shreiking whistle. Sounds like a teakettle on full boil. Or several tea kettles. It's not the alternator, water pump, or power steering pump. The sound seems to be coming from the area just above the intake manifold and the front half of the engine.
I could use some advice on this one.
Some pics of the project are below in my sig.
