figured i’d do a couple dyno pulls to make sure the car was still running like it should, the day it came off the dyno… and to my surprise, she’s running just as good with ZERO knock across the board
no tweaks nothing, just 24-25psi 93 octane, the way it was tuned by JR himself…
363awhp/341tq
on a fuel injected car it dont matter if its dyno,s in the middle of winter or 90 deg … the comp will make the changes needed unless the tune if fucked . thats why all cars that are injected have a air intake temp sensor
It really depends on the car then, I guess. Normal driving might (and should) be fine if the o2 sensors are ok, but the P.E. fueling curve isn’t affected by temperature changes. Doing WOT blasts down the highway in the middle of winter on a summer tune is a race against time (and a melted piston or two).
The reason I say that is because (for example) a car that’s commanding an 11.7:1 AFR at WOT may be OK in the summertime and not experience any knock or lean symptoms, but in the winter the cylinder airmass is a lot more dense. You really need to add fuel to the wot tables in order to be safe in the cold weather.
Running lean up top when it’s cold is never a good thing, lol.
The MAF doesn’t know how dense the air is. The cyl airmass is estimated by the ecu using math calculations. So if it sees the same amount of air being sucked in and uses the parameters that you told it to in the summer time, it then sprays the same amount of fuel and the car will obviously be lean. This is why MAF-only tunes can be dangerous, especially if you run the same one year round.
Of course, whether or not a narrowband o2 will pick up on that is anybody’s guess, however I can guarantee you that they will not under heavy loads and WOT because the computer uses a preset afr at those times and ignores the input from the o2.
Maybe Pete’s car/ecu operates a bit differently. Does the evo have a wideband from the factory?
Granted I don’t know much on the matter, but I’m referring to a MAF that bases it’s voltage on how much a heated wire/film cools as intake air passes over it. That means it knows exactly what the air density is, because air density is a function of temperature and humidity, no?