Cam Lockout tunes

[Medusa5oh]

Stepping beyond the obvious loss of power and drivability from locking them out mechanically, I'd go with the tuned lock-out to give yourself the flexibility to go back to not locked if you don't like the locked cams.

What is "chop"?

Chop is the slang term for the noise overlapping cams makes, most notably in older pushrod engines.

Sponsored

 

[Medusa5oh]

I’m still a little lost on the reasons why. If a “ghost cam” tune has too much “chop” then any decent tuner can easily remove some idle overlap to calm it down a bit.

If you choose to lock the cams then you have to choose what timing to lock them at.

You could lock them at 0, 0 which is the cold start and de-energized state. It’s not a bad compromise but won’t lope (if that’s your thing) and you’ll sacrifice fuel economy, torque below ~5000 rpm, and power above 5000.

If you want some lope, I think 0, 15 would give a little lope, but you’d make the torque and power compromises listed above.

WOT at 5000 rpm seems to be about the breakpoint where all possible intake cam timings break even. You can advance up to 20 deg and gain torque below 5000 while sacrificing power above it. You can retard up to 30, though 10-20 seems to work best. This will scream above 5000 but be a turd below 5000.

Or you could leave it functional and get all the low end plus the top end, not having to sacrifice anywhere.

I did something similar to this while tuning the mapped points. I believe it’s been described as “mapped point isolation” where you electronically lock the cam timing at a single mapped point and fully tune the spark/torque/SD for that mapped point, then move on to another. Once all mapped points are tuned, you turn the tivct back on and you’re done. In doing this I was able to get a sense of how each possible locked cam timing combination drove. Since ford uses a torque-based system and each cam timing has its own torque calibration, you actually couldn’t tell any difference at part throttle between, say, 20, 0 and -20, 20 except fuel economy, idle quality, and WOT. I can say from experience that 20, 0 was a slug down low and -20, 20 ran out of steam up top like an LS motor.

So if I were to do anything I’d just do a tune “lockout” like you said rather then mechanical, however the general consensus is that it’s not worth it, so I’m probably just going to move on from this idea/dream and on to the next thing. I appreciate your in-depth feedback though.