cold weather fun

So besides my car not being able to start unless it has been plugged in for a couple hours when it nears 0°F I'm seeing some increased performance and some other odd issues. First off I'm getting more boost than I'm used to. Normally I max at 5 but in this cold I've been seeing just over 6psi. I would think with how hot the turbo runs it wouldn't be the wastegate having troubles opening, or maybe it's just that since the air is colder and more dense that I see increased levels anyway. Not that it's bad, it was just a little surprising. The other thing is the fuel pump is noisy as hell in the cold. This has always been the case, more so when the tank is full. Dunno if that means it's going or not. The increased performance is simply stemming from the cold air, I've always had pretty good performance in this weather. I think it also comes from the fact that it was tuned in this weather

Todd, have you thought of marketing a block heater device that not only utilizes a smart heating element that comes on and off the keep the coolant temps at a certain range rather than always on (so you can leave the car plugged in all night without hurting your heater or your energy bill), include a battery warmer with the same feature, and maybe even a way to operate the water pump to circulate the warmed coolant to the rest of the block? It's sort of an all-in-one engine heater for cold climes.

 

I'd look at replacing your batter for the cold start issue.

Also, my experience has been in colder weather that I get less boost, since the air is already denser, there's not as much compression needed to get to the desired level. (I guess it depends on the software you're running)

I also notice improvements at these temps. Colder air dense + timing can be more agressive = fun

 

Now, where can we all go to put that fun to use?

 

The battery isn't the problem, it turns it over plenty fast. Starter motor isn't a problem either. It just doesn't like starting in the cold. It's always been that way in the winter, nothing new to me. I just have to plan on having a place to plug in if I'm going to stay somewhere for a day.

You shouldn't see less boost. The psi stays the same, it just takes less airflow to create that pressure since the air is denser. I am seeing some really low intake temps at the intercooler on days like this }
I think there's some other reason that I'm overboosting, but my maps go up to something 30psi so I'm not too worried. I think the timing is so retarded at pressures exceeding 8psi that nothing too serious should happen. It was just interesting. Could even be that my gauge is acting up. Speaking of which my EGT stopped working... I think the probe fell out [xx(]

 

The nice thing about the UTEC's closed loop boost control is that it's essentially independent of weather. I don't know what algorithm they used, but it's nice that I can set it up for X amount of boost at 70F and get the same amount at 20F.

 

Controlling the boost on my car is a little bit trickier. I'm not sure how the WRX does it but I pretty much have a wastegate spring controlling it and nothing between that and the engine to alter it. Does the WRX engine use a solenoid to control boost?

I figured the rumor about leaving the heater on all night was bogus. It's pretty interesting that you can hear it hiss as soon as you plug it in though

I leave it plugged in at work for most of my shift since nobody there cares about the power consumption. Not yet anyway. In the UP almost all places have outlets for employees cars I noticed, I don't see why it should be any different here.

 

Yeah the WRX factory setup uses a boost control solenoid. The UTEC lets you choose between directly controlling the duty cycle of that solenoid (open loop control) or setting target boost levels in combination with a boost gain and letting the UTEC decide how to alter the solenoid's duty cycle to achieve your desired boost curve (closed loop control).