Serious street performance, modified oval track and bracket racing. Mid-range to 7,000 RPM. Dart Iron Eagle Platinum 23° 215cc heads are for big cubic inch, high RPM applications which favor peak power over low end flexibility. Long wearing Bronze valve guides, screw-in studs, multi-angle intake seats and hardened and radiused exhaust seats are standard. Best of all, our precision cast ports produce outstanding airflow without time consuming porting.