The new intake valves were stainless steel, and the exhaust valves were Inconel with a ceramic coating. The Intake valves were back-cut and blended to improve flow:
For more information about head porting and polishing, see the Wikipedia article.
Head Games:
The new heads were from an AAH engine, they were ported, cleaned thoroughly, flow tested and the ports were flow balanced. The AAH heads use a hardened valve spring seat that allows for higher rate valve springs. The factory spring rates were 134lb/in. The new springs are 172lb/in. This allows for more closing force at high rpm and high boost levels to avoid valve float. Valve float occurs when the valve spring cant close the valve fast enough to follow the cam profile, allowing gases to slip by that shouldn't.
The new intake valves were stainless steel, and the exhaust valves were Inconel with a ceramic coating. The Intake valves were back-cut and blended to improve flow:
For more information about head porting and polishing, see the Wikipedia article.
The new intake valves were stainless steel, and the exhaust valves were Inconel with a ceramic coating. The Intake valves were back-cut and blended to improve flow:
For more information about head porting and polishing, see the Wikipedia article.
