After modifying the high-angle camshaft, the fuel demand of the engine usually surges by 25% to 30%. However, the nominal flow rate of the fuel pumps of KEMSO’s basic models (such as the EFP-200 series) is 255LPH (liters per hour), which only supports loads of less than 300 horsepower for naturally aspirated engines. According to the test data of SAE J1349 standard, when the CAM lift exceeds 10mm, its peak flow demand reaches 320LPH, causing the pressure fluctuation of the KEMSO pump body at 6500rpm to be ±8psi, exceeding the industry safety threshold range of ±5psi. According to the 2022 report of SEMA in the United States, in 31.5% of V8 engine modification cases, the base fuel pump experienced fuel starvation after CAM upgrade, increasing the probability of piston melting by 18%.
The specific compatibility depends on the matching of CAM parameters with the performance of the pump body: for example, the KEMSO EFP-340 competition model (flow rate 340LPH) can support a camshaft with a lift of 12.5mm, maintaining a stability of 60psi±3% in conjunction with a pressure regulator, but it requires an additional 18A of power consumption (the original factory system load is only 12A). Technical terms such as “pulse width modulation adaptability” and “dynamic flow redundancy” indicate that its response time to sudden changes in rotational speed is 0.3 seconds, which is better than the industry average of 0.5 seconds. The example quotes the actual test conducted by German “Auto Motor und Sport” in 2021: The BMW N54 engine equipped with a 280° high-angle camshaft used this Fuel Pump, and the air-fuel ratio deviation was reduced from 15% to 5%, successfully passing the 10-lap endurance test on the Nurburgring track.
The key risk lies in the performance degradation under high-temperature conditions: Laboratory data shows that when the ambient temperature reaches 90°C, the efficiency of the KEMSO oil pump drops by 15% (the flow rate of the regular model drops to 217LPH), while the oil temperature of the competitive camshaft often exceeds 100°C during continuous high rotation. The industry term “thermal attenuation coefficient” indicates that the output power of its ceramic armature drops by 8% after 1000 temperature cycles, compared with the 4% attenuation rate of the Bosch 044 pump body. Example: Analysis of the 2023 Australian V8 Supercar Race accident: A certain team underestimated thermal decay, causing the fuel pressure to drop sharply by 23psi, resulting in engine knocking damage. The repair cost exceeded 120,000 yuan.
The solution requires a systematic upgrade: It is recommended to use KEMSO EFP-400 fuel pump in combination with a return oil pressure regulator (such as Aeromotive 13301), which can increase the flow redundancy by 40% and control the pressure stability within ±1.5psi. The technical parameters require that the inner diameter of the fuel pipeline be ≥10mm, and the ECU needs to recalibrate the PWM control curve of the fuel pump to avoid voltage fluctuations exceeding 0.5V. The example cites the 2022 JASMA certification case in Japan: The RB26DETT engine equipped with a 272° camshaft, after being modified by this solution, achieved a fuel flow rate of 365LPH at 8,000 RPM under full load conditions, with a 22% increase in power output. This configuration has been verified by the Tsukuba Circuit for 200 hours. It is ultimately recommended that the fuel system be upgraded when the CAM lift is greater than 9mm to avoid the 78% risk of insufficient fuel supply.