Unmatched Performance & Durability since 1983
JPrecision specializes in high performance machining of engines components. We let your local qualified mechanics to do the final assembly. Contact your local dealer for more details.
It only takes one pass on a dyne or a quick ride on an open road to fully appreciate the exceptional performance offered by JPrecision heads. Cylinder heads modified and upgraded by JPrecision are simply the most powerful and reliable that money can buy.
Unmatched Performance & Durability since 1983
JPrecision specializes in high performance machining of engines components. We let your local qualified mechanics to do the final assembly. Contact your local dealer for more details.
It only takes one pass on a dyne or a quick ride on an open road to fully appreciate the exceptional performance offered by JPrecision heads. Cylinder heads modified and upgraded by JPrecision are simply the most powerful and reliable that money can buy.
Adrenaline and Satisfaction Guaranteed!
Adrenaline and Satisfaction Guaranteed!
STAGE II
This head features our upgraded intake and exhaust port design and is CNC ported for optimal efficiency. The ports are then fully hand finished and have proven to provide a more efficient flow rate. This is a perfect performance upgrade for your street performance needs.
We offer the stage II upgrade for 883 – 1200 conversion and for Sportster and Buell 1200 engines, please call for more details.
STAGE IVB – High Torque Heads
The Ultimate heads for Sportster & Buell engines.
We redesign and raise the intake port by welding to increase velocity,allowing for a crisper throttle response. We install new oversize seats and larger valves, relocate the spark plug and enlarge the ports accordingly.
HEAD WORK OPTIONS
MANIFOLD PORTING
We port the manifold to optimize the airflow and to achieve a better fuel atomization through our proprietary finishing process.
COMPRESSION RELEASE VALVES
We machine the heads to install the compression release valves in line with the spark plug for an easier access and a better look.
Recommended for Sportster engines from 88 “and up.