Technical Cast intake flaking pieces internally

I used to see the same problem with deteriorating cast iron on Ford FE motors a bunch. The heat riser valve on the exhaust manifold would stick and that crossover passage would see a lot more heat than usual. Sometimes they would burn all the way through to the valley area

 

Yup, I had a 390 intake do that. I was cleaning things up ready to reinstall and right below the carb I could see the floor of the plenum was misshapen. A few light taps with a hammer and punch and I was right thru into the exhaust crossover. I tossed that manifold and put a different one on. Should it come to that, it might be a little tougher to find one for an old baby hemi.

 

No, you don't need the heat riser. All it does is forces exhaust through the crossover so that the carburetor and intake vaporize the fuel mix more efficiently from a cold startup. The heat riser has a bimetal spring that opens it after it warms up a bit. Leave the heat riser off. The engine may be a little cold blooded and take a couple minutes to warm up, but that's the only change you would notice.

 

Center of the Galaxie. If it came down to it, I also have a 4bbl manifold I could use. This all jus fortifies the fact I’m not getting rid of any parts I have. They are hard to come by

 

Ebbsspeed. Perfect. I shall leave the riser off

 

A crossover pipe is not needed to use a heat riser , how would you suppose an engine with factory dual exhaust would work . the exhaust from the heat riser side is forced through the intake heat port , thus heating the manifold .

 

Perfect because I’m going to run dual exhaust. Thank you