[El Co 406]

Last question for today. I was given a 350 and am trying to decide whether or not to work with the current heads. They are cast iron stocks with the casting number 3991492. Are there any benifits to using cast iron heads and has anyone used 492 with any sucess? The engine will most likely be dropped into a late 60's/early 70's Chevelle. I'm looking for decent power, but nothing too drastic that would be unreliable or needs constant work.

thanks

[barnym17]

These are exellent stock heads 64cc large valves, capable of well over 400 horsepower.However that being said if they need a lot of work vortecs would be a better option money wise.But if they are good shape and you are not building a record setting car use em.Oh by the way you will probably get many replies saying junk'em and get new aluminums or vortecs or whatever old tech is junk.I call B.S these old heads rock and rolled.

[El Co 406]

They have been sitting on an old 350 unused for about 8-10 years, I'm thinking of having them hot tanked and checked for cracks since they sound like they can put out the power I'm looking for.

[F-BIRD'88]

One of the best factory heads to start with. You can create a very good street performance motor using these heads.

[techinspector1]

Runners are 157 intake, 62 exhaust. Valves are 2.02"/1.60". Flow figures taken from info by Stan Weiss are as follows:
0.300" valve lift 173/125
0.400" valve lift 198/137
0.500" valve lift 206/141