How to we improve the Low-End power and Throttle response for a Proton Persona

Lacking of low-end torque and throttle response is always the problem that many Campro engine owners complain for. However, the top-end powe...

Lacking of low-end torque and throttle response is always the problem that many Campro engine owners complain for. However, the top-end power is always a cool thing which Campro engine owners brag about. Even though Proton tried to improve the low-end torque by introducing the IAFM but the reason not really satisfying. I have tested my friend's Persona and felt that there is still a dip (lack of power) around 2K - 3K rpm. 

In order to improve this problem, I have introduced my friend to Adjustable Cam Pulley (ACP) and explained to him the advantage of it. In short, advancing or retarding the cam will move the torque curve higher or lower in the rpm range.

Advance: 

• General Effect: Improves low-end power and throttle response. 
• Intake Valve Opening Event: Happens sooner.
• Piston to Valve Clearance: Decreases intake valve clearance. 

Retard: 

• General Effect: Improves power at higher rpm.
• Intake Valve Opening Event: Happens later. 
• Piston to Valve Clearance: Increases intake valve clearance. 

Read more over here. 

Cut the crap and let's start! The installation of the ACP is pretty straight forward for Campro engine and he chosen works engineering ACP for this upgrade. 

Firstly, you need to remove the cam pulley cover. Secondly, locate the  tensioner and loosen it. Then, loosen the nut and take out the OEM cam pulley. 

After that, install the ACP back in place and adjust degree by moving to arrow towards "A" for advance timing (Do remember that 1 marking is equivalent to 2 degree crank). Lastly, install everything back in order and start the engine.  *** Ignore the hairy arm of my mechanic. 

Once engine is started, we monitored is there any engine knocking and went for a test drive to test the improvement. For this round, I had suggested to advance 2 degree only for the time being. The reason is to let him familiarize the improvement and we shall re-tune in the near future. We have yet to test the full range of the rpm but according to my friend's feedback, there is improvement in the throttle response. 

The car is far from done yet and my friend has a list of upgrades in the near future. Therefore please stay with us and do drop an email or message at the comment below if you have any question.