Stock ATS-V and CTS V-Sport fuel system consists of a low pressure electrical pump in the fuel tank, and a high pressure mechanical pump on the driver’s side exhaust cam. The stock fuel systems are already starting to have difficulty keeping up by 17 pounds of boost and 500 whp. This problem occurs when boost is brought in quickly and torque starts to peak. It is also exacerbated in the overdrive gears, and engines have been lost for this reason. We see the high pressure drop off on every ATS-V we tune, as soon as boost is increased. The more boost we add, the worse the problem gets.
Here are some estimated performance capability numbers using Tapout fuel system solutions. The fuel system components themselves won’t produce this much power. These are just estimates of what each fuel system upgrade should be able to support safely.
- 500 whp (gasoline) stock LPFP and stock HPFP
- 600 whp (gasoline) Tapout Fuel Cam
The Tapout LPFP can be added to any of the above to provide a little extra padding or safety margin.
This is a factory GM ACDelco camshaft with modified HPFP lobe. We have reground the fuel lobe to have 6.35mm lift instead the stock 5.25mm. This is the maximum possible within the hardened depth area of the stock camshaft. At 6.35mm this results in 21% more HPFP volume capacity compared to stock cam. No custom ECM tuning is required for this fuel cam by itself.
Fuel cam adds stroke to HPFP, and HPFP internals add bore. When used in conjunction, they provide ~ 65% more high pressure side fuel volume.
Custom tunes and any performance parts that could affect vehicle emissions are intended for off-road use only and not to be installed on any vehicle that will be operated on any public roadway. Not for sale or use in California.