chevy iron head
 

in modified class -you can run any cast head as long as it has in my case a gm casting number.the 4446 vortec looks best for the class with a 10.5 weight per cube and a 366 cube limit and a 3300 car-.Can you all give your opinion and advice ------THANKS-- FIREBIRD

Re: chevy iron head
 

Yes, the Vortec 446 casting is legal in SS/CS class. Michael Mans has his SS/CS engine for sale on this site and it is a record holding engine.

Re: chevy iron head
 

I do believe some of these vortec heads are getting hard to come by nowadays. There are other heads approved for the combo. I think they are RHS or Dart.

I stand corrected. the heads my frriend uses I thought he said were no longer available. sorry.

Re: chevy iron head
 

25534445 is the part number for the bare cylinder head and 25534446 is for the whole assembly. They are still available from many vendors. I believe Michael mans tried all the other approved cylinder heads and he still made more power with the Bow Tie Vortec head.

Re: chevy iron head
 

I know Robert Swartz has a new set of Vortecs from Parson and Meyers for sale. Not sure the casting/part number but you might send him a PM

Re: chevy iron head
 

Do not confuse the 906 casting OEM production Vortec cylinder head with the 445/446 Vortec Bowtie racing cylinder heads. They are two different animals.