I have been talking to Chronohunter recently about possible cam gear timing changes that may help at altitude. The theory is that by advancing the intake and retarding the exhaust cam you effectively raise compression compensating for altitude which ideally results in faster spool.

Here is what I found

Relevant Mods:
03 Evo 8
SMART Xede
Signature full exhaust with cat delete
264 intake, 272 exhaust
Vishnu cam gears
XEDE flash
Standard 91 Octane SMART map from Vishnu

-3 Intake, -3 Exhaust
124077.025
124077.026

+1 Intake, -3 Exhaust
124077.031
124077.032

+3 Intake, -3 Exhaust
124077.036


Considerations:
These settings have the potential to produce more knock. This was carefully monitored and no more noise was registered than the standard -3, -3. With the +1,-3 and the +3,-3 settings there was considerably more lope at idle.

 

After excitedly seeing JTB's results I called him up and Shiv who ok'ed the change on my car and....WOW is all I can say... it feels like a stroker

before you flatlanders get all excited it only works at altitude (>5k or so) where the air density is so low. At lower altitudes you would see a big hit in top end that wouldn't make it worthwhile. We run out of turbo so soon up here (look at JTB's graphs and compare them with a sea level run) that it has little effect on our already weak sauce upper rpm's but give a big kick in the pants to our torque curve making it well worth while. I expect a decent increase in fuel economy as well due to the increased efficiency (you can feel the difference from idle on up). Also noticeable is less lag between shifts (that is real handy on the 5spds big gap between 4th and 5th gear).

all in all a fine experiment and thanks to JTB and Kris at Logic Imports for trying it out

 

I was reading this thread and was always wondering the same thing.. I have just about the same types of mods and would like to advance timing up front and retard the exhaust, but dont have a dyno to really do it right where I am at. I am at an altitude of about 2000ft, but seem to notice a bit more of a lag than where I came from (phoenix, arizona). So my question is, what is a good measure to show what my gain is over the whole band without a knock sensor or datalogging equipment?? I do have a Wideband and am purchasing the evoscan, which I understand can help me in the knock sensing area. thank you up front for any help. Mike