Some local guys swear by tuning (entirely) on the street as opposed to on a dyno because as they say, you don't drive all day long on the dyno. We're talking street cars, daily's and weekend warrior Subaru drivers if you're wondering. While I see their theory I don't see the practicality - there's no controlled environment, how do you establish baseline parameters with all the variables of driving on the street in random weather. I also don't entirely trust the general judgement of some of them... however I admit tuning an ECU is what I know least about.

Posted By yo vanilla on 12-03-2010 06:27 AM

 

Some local guys swear by tuning (entirely) on the street as opposed to on a dyno because as they say, you don't drive all day long on the dyno. We're talking street cars, daily's and weekend warrior Subaru drivers if you're wondering. While I see their theory I don't see the practicality - there's no controlled environment, how do you establish baseline parameters with all the variables of driving on the street in random weather. I also don't entirely trust the general judgement of some of them... however I admit tuning an ECU is what I know least about.

I am a controlled environment kind of guy by nature. But what's the right way to do this in terms of both safety to equipment and performance?

IMO, they're just being cheap and that's why they're justifying street tuning.  The dyno is by FAR the best and safest place for tuning.

You can get a good baseline on the dyno, especially if you're only tuning WOT.  But to really get a good calibration for overall driveability, you need to do it on the street.  A dyno can not simulate the airflow nor transients in normal driving.  One of my friends is the calibration engineer for TRD; he does every calibration for all the TRD supercharged vehicles.  Almost all of his calibration work is done on the street; I think he said he typically has a car for three months to fine tune the calibration.  I know for the new Ford Powerstroke engine, for altitude calibration, they had a fleet of trucks they took out to Colorado and just did runs up and down the mountains there to work on their calibration.  The OEMs also have their test tracks to do the WOT calibration work.  Since TRD is out here in LA, they'll rent out Willow Springs for a day to do calibration work.

In short, you can get a decent tune on a dyno, especially if it's only WOT tuning.  But to get a really good tune, it needs to be fine tuned on the street./track.

Posted By spdracerut on 12-04-2010 10:21 AM

You can get a good baseline on the dyno, especially if you're only tuning WOT.  But to really get a good calibration for overall driveability, you need to do it on the street.  A dyno can not simulate the airflow nor transients in normal driving.  One of my friends is the calibration engineer for TRD; he does every calibration for all the TRD supercharged vehicles.  Almost all of his calibration work is done on the street; I think he said he typically has a car for three months to fine tune the calibration.  I know for the new Ford Powerstroke engine, for altitude calibration, they had a fleet of trucks they took out to Colorado and just did runs up and down the mountains there to work on their calibration.  The OEMs also have their test tracks to do the WOT calibration work.  Since TRD is out here in LA, they'll rent out Willow Springs for a day to do calibration work.

In short, you can get a decent tune on a dyno, especially if it's only WOT tuning.  But to get a really good tune, it needs to be fine tuned on the street./track.

OEM tuning has a lot more parameters to look at than your average piggyback ECU used by most people with modified cars, though.