|
Slide Throttle Street Prepared Engine |
This tuned-Port Fiat X1-9 1500 SP motor uses Haltech user programmable fuel injection and a G-Force built prototype twin slider throttle system to eliminate butterflies. This results in high flow velocity with no flow obstructions for low end torque tuning, while still retaining maximum breathing capability at higher RPMs. The large chamber for the stock injectors--positioned in the most critical area of flow--was eliminated. Computer modeling and extensive flow bench tuning yields 107 ft-lb. torque from a stock block, stock head and stock cam Fiat 1500! |
|
|
|
| G-Force created a helmholtz resonance port tuning model to optimize the lengths and diameters of the ports. Measurements were made to establish space restrictions under the engine lid and the system was custom machined in the G-Force shop out of billet aluminum. Seven heads were checked for casting match and flow benched to optimize flow with the new throttle. Stock head components were checked as well. Then the maximum material was milled from the head according to SCCA Street Prepared rules. Nothing was done to the stock block save careful assembly. The engine was dyno tested on a Stuska Dyno and cam timing was optimized by the use of an adjustable cam pulley. Then, to meet the rules, the pulley advance was measured on a custom built fixture and multiple stock Fiat cam pulleys were checked for a match. Finally, a G-Force machined flywheel was installed. This engine pulls stumps compared to many cammed-out and ported motors, and sounds like one, too... |
|
|
Exhaust Header |
G-Force has completed development of a unique equal-length header for the Mazda 12A rotary engine. Designed for IT, SP and street, the second of three initial prototypes yielded significant performance improvements over the best Racing Beat header. The header uses several proprietary concepts (not shown) not yet seen in any currently available production header. Regrettably, due to market restrictions, manufacture of this header is no longer being considered and it is used solely in the G-Force development racecar. |
 |
