Sorry if I'm beating a dead horse here, but I had a question about flashing evos. I'm staying at school in New York and I was thinking about flashing my car soon, since I've gotten a charity donation of parts. But I was wondering if I had to flash my car with the changing seasons? I remember hearing that a long time ago, but I just wanted to confirm my thoughts and plan for the future.

Thanks!

 

It really depends on the methods used to tune and the "buffer" left in the tune. Basically, when it gets colder the air gets denser ... this means that you will likely hit higher boost levels and run leaner AFRs. The opposite is true for hot air ... thinner, less O2, less boost and richer AFR.

If you get a fairly safe tune in the fall or spring in mild weather, you might be good with it year round. however, if you tun in summer or winter you are likely to see dramatic shifts when the opposing season rolls around.

Using the ECU to control boost can help with this if you keep the stock boost correction enabled. This will allow the ECU to correct the boost and regulate the load levels regardless of weather conditions. The AFR will likely still change though.