[Tigers] aluminum heads

[rab65tiger at aol.com]

My reading indicates cast iron heads may be superior for performance, IF flow numbers are the same, and some real world factors like hardened valve seats for unleaded gas are included, higher octane gas, the cast iron may be superior to aluminum heads.? The recent explosion of available aluminum heads with newer designs, typically out flow stock vintage cast iron heads, and the included hardened valve seats are a bonus.? The cost of port and polish and adding hardened valve seats to cast iron heads, combined with some weight savings, and maybe the possibility of running a little more compression without race gas seems to make aluminum heads an easy and cost effective solution. The after market is probably swamped with aluminum heads do to a lower cost to design, manufacture and machine compared to cast iron.? One caveat on Tigers, many aluminum heads are dimensionally different than OEM castings, making firewall clearance and header/ exhaust interface a concern.? Some aluminum heads utilize stock dimensions and exhaust port locations, some alter these dimensions.? Some headers offer different size tubes, that may align better with the exhaust ports on non stock heads.

Randie