Thread: Tuning for S4/S3 cams?

Tuning Pros,

For the people that have S4/S3 cams, what should the tuning process look like to get the most out of them? I know there are tweaks to the idle, but I'm talking more about the power band. Is it worth it to customize the fuel/timing maps for the cams? If so, what would the changes look like?

Thanks!

pm'd

Since these cams introduce more air, engine runs more efficiently thus you need less timing have a complete burn. Thus with upgraded cams you want to run less timing generally. Also Cams move up or down the powerband, thus you need to retune your AFR's for that.

So keeping the timing values the same pre-cams would introduce detonation, a decrease in power or both?

Depends on how fine tuned your current tune is. If it's a safer tune then it's not running MBT (Minimum advance for Best Torque), thus your existing map would actually make more power with VE (Volumetric Efficiency) increasing modes. If your already tuned for MBT for that specific setup and you introduce a VE mod, you are now running past MBT and will start loosing power, due to the piston working against the working flame front (remember this post?).

Some more fun reading: Calibration guides