Cam Timing... Removed?

I watched your latest update and I’m excited about the coming updates. I’m curious and maybe a little confused as to why the cam timing was removed and added to the cam profile? Cam timing is a very powerfully tuning tool. Not only does it obviously move the power band around but it effects the dynamic compression ratio. Retarding timing will reduce compression and effectively make an engine less prone to knocking and/or slightly reducing the (Ron) required. Advancing will have the opposite effect. So why removes such a powerful tuning element?

Umm… you are mixing up cam timing and ignition timing. Cam timing is removed because it didn’t make any sense:
Let’s say your cam profile is optimized for action around 7k RPM, but you choose your timing to be optimized for 3k RPM… you now have an engine which runs shitty at all RPMs, yay! So basically there is no real choice involved, timing needs to be set such that it is “right” and not “wrong”… this was not necessarily true for Automation pre-Revamp, but it certainly is in Automation now. Conclusion: it only makes sense that it automatically is set to the “right” value, as there would be no real choice anyway.

Ignition timing is still in and indeed very important.

What he says is actually true in terms of the effects of cam timing, but indeed, as killrob says, its kinda rolled into the cam profile now as its all part of cam design

If a motor cant breath well in the top end and it’s not restricted from intake or exhaust you could choose to make the cam more aggressive. Adversely it can substantially sacrifice bottom end power, response and a smooth idle. If the cam timing is advanced you trade off at little top end power to regain some of my low end power while keeping the larger top end gain. Cam timing is a nice way of shaping your power curve, while it may not lead to drastic gains and could lead to a poorly tuned motor it is an essential tuning element. Removing it takes the detail out of tuning an engine, and the details is where the fun truly comes in.

In my EVO, adjusting the cams helped reduce the turbo spool up by almost 1000 rpm. Because of that my peak torque moved down a lot!

The main reason why its gone is that it was kind of already specifying something that the cam profile slider was specifying, the cam profile slider is all about lift, duration and timing, and what rpm range its optimized for, and so the cam timing slider kind of was at odds with that as the profile slider would theoritically set one timing, then the cam timing slider would change it again, thus it really didn’t make any sense to have two controls for the same thing.

Whilst aftermarket users like us (I’ve done quite a bit of tweaking to my cam timing on my MX5) can further optimize a cam to our application, if we were a manufacturer we would have got that cam timing correct in the first place and it would have been part of the overall design of the cam (aka the cam profile slider)

Also do remember that whilst we are trying to be detailed, being detailed alone is not a goal, we’re not trying to write an engine simulator, and gameplay considerations do need to take precedence in some cases such as this.

Thanks for the info, I understand.

No worries, always happy to explain why we do stuff the way we do :slight_smile: