I'm looking at a couple tuners in Colorado as it's the closest thing to my physically and I was wondering what my options are for tuning at one altitude and going to another one. For example: there I believe the elevation is over 6000ft, where I live, I'm around 3000ft. What does a tuner do to compensate for the elevation change? Just curious for a technical answer as I would like to think there should be some sort of parameter to compensate for different elevations. I think it would be retarded for a person to have to retune the car all the time for different elevations. Keep in mind, I'm looking for safety. The way I understand it, going from a higher altitude to a lower one, would cause the car to run leaner.

Any tuners out there that could elaborate?

 

Bump for some answers. I thought we might have some tuners out there but I'm now wondering. I read through the hondata flashpro help and I'm so frustrated now. I didn't see anything for elevations just temps and knock limitations/adjustments, etc.

 

The car is Speed Density, it will see the lower pressure and command the appropriate fuel and timing. You'll see slower spool and the turbo will work harder for the same boost, but the tuner should be able to replicate many of the changes seen with the dyno and work it out (vary load, increase/decrease boost, etc).

 

Didn't see anything in the original post about the poster having a turbo on board. I would be interested in the answer to this question for a NA configuration as I have similar concerns with where I come from. I am in Phoenix now and will have a flashpro done and a tune but I don't want it to be an issue when I go back to 4000'. Your comments suggest that the ECU will accomodate the change in altitude automatically but I'd like to hear from somebody who knows difinitively one way or the other. Thanks.

 

If the tuner does a good job, you'll be fine.

 

Keep in mind that there will be less pressure on the exhaust side due to the lower baro pressure. This will change fueling requirements at a given load/rpm cell.

 

A tuner should have no problems tuning for elevation changes....

 

there is compensation tables but its not always perfect.

I actually drive from 3200ft to 7000ft on the way to work. I got data logs in the canyons and up at 7000ft to really fine tune the different elevations.

There was never really a problem with different elevations, just a little less than ideal afr.

 

How can this be acomplished on the dyno? You would need to simulate a barometric pressure change in the dyno room. Your average tuner does not have that ability

Varying load/ boost will not have the same effect.

 

Although you won't be able to replicate everything on a dyno, you can plot based on trims. I do this on road tunes for temperature. All though each car is slightly different, there is a trend and I have generic numbers I'll put in for temp compensations.

Example: Subaru MAF's report less flow than actual when IAT's are hot and more flow than actual when IAT's are cold. You scaled in roughly a 10F temp range, change the reference number in the table to the median temp that you scaled in, then 0 out that entire row. From there, you work the warm and cold ranges for the MAF scale.

Remember, you get barometric changes at a single location through the day/week/year. You may not get drastic changes like you do driving up or down 4,000 feet, but you will see some of the effects. I am a big fan of road tuning, but it's really for getting a spot-on tune in the fine-tuning portion. There are things dyno's make MUCH easier and quicker.


I suppose you'll have to explain this one. You can do quite a bit by varying load, boost, vacuum, etc. If you can control temperatures (within reason), you can do a pretty good job.

I used to live in Denver and is where I got started tuning back in 2004. When I left Denver in 2008 and moved from 5,400ft to 900ft, I didn't have any tuning issues. I did back off timing before the move as I was running timing pretty high for the altitude and the "high altitude timing tables" did not make any switch until I was higher in elevation than Denver, so I did manipulate my base timing table. Other than that, AFR's were on, even as I started increasing timing closer to where I had it.