Head selection is a critical element of any engine build. Aluminum is a much better conductor of heat than iron. Switching to aluminum heads allows typically a full point of compression. That by itself is a big deal. Once past that decision, it comes down to which of the many options offers the best combination of performance and cost.
Dart’s SHP (Special High Performance) 23° 200cc cylinder heads provide an affordable option for larger displacement street performance engines. The SHP is designed to work with most off the shelf components. These heads are intended for street performance, restricted oval track, and marine performance upgrade. Mid-range to 6,500 RPM. They work best with 383-434 cubic inch engines.
The SHP head’s precision cast ports are designed to offer excellent flow and power without the need for CNC porting. Optimized chambers increase combustion efficiency, and multi-angle intake seats and radiused exhaust seats dramatically increase performance. Manganese Bronze valve guides increase the life of the head.
A set of these heads (64cc chamber size, fully assembled) topped off the 383 stroker in the photo below. This pump-gas, hydraulic-roller, street cruiser put out over 500 hp on our dyno with no porting or special work. Pretty much out of the box. That's big performance at a really solid price!
Want even more? We've just developed a program to further tune up these heads with a CNC valve job on our Newen Contour and it rocks! Here is a before and after shot:
Here are the flow numbers:
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All-in, you're looking at better than a 5% increase in flow which translates roughly into increased horsepower. That's 25 hp on a 500 hp engine. At $150 per side, that is cheap power.
Order yours now in either chamber volume, bare or assembled, and either "as-is" or with our custom CNC valve job. Call us now at 815-725-2727 with any questions.
Prices shown are for single heads with free shipping in the continental US.