Dyno during cold weather?

[99 gst spyder]

I've search and I could not find anything. I'm ready for a dyno/tune at the dyno shop. It's below 4 degrees now/here in MN, but should warm up into the 15 degree mark next coming up week. The shop/tuner said the cold weather can effect the tuning process or make it a little more work to get it tuned and doesn't want to take the chance it running on limp mode or something. They said they can try but it'll take more time if I wanted them too.

Is this a good idea to get a dyno/tune during this kind of weather or should I wait untill spring time when it gets warmer? What is the effect and non effect during the cold weather and warm weather?

Thanks.

 

[Archer Fabrications]

If you balls out in cold air youll knock and blow your motor then when the air is hot n thin. I'd wait always tune balls out in the hottest weather that way you alwaya have saftey margins when the air is thick

 

[boost97gst]

If you get a really nice tune in 15* weather then use that same tune in the summer you wont be happy. The other way around works though: summer tune will be fine in the winter. Thats what ive found to be true.
Thing that really really counts here is IAT. Thats the big x factor between summer n winter tuning. Also, to some extent, coolant temps can affect change as well.

Edit: you will log more lbs/min the colder the ambient air. Cheap vrsf IC or an ETS,its bound to happen. More flow=more power. Cold air and (especially) turbos get along really well!
As Danl says the IC does make a difference.. to an extent.
Lets say you have 20* ambient and IATs are good, maybe lets say 50*, Now say youre in the middle of summer and ambients are 95*. You think that ANY intercooler is going to drop temps past ambient? Well, maybe an air/water IC with ice in the reservoir, otherwise no. Even if you're 100% efficient and the IATs on that 95*day are 95* too. You can see how it all works. The air going in to the engine post turbo is always cooler on colder days, denser, and will net more power.

 

[danl]

It really depends on the setup. My car has similar timing requirements in the cold as it does in the heat. I also have quality linear injectors and a properly scaled ECU. Thus the ecu fuels the engine correctly.

If you are running a turbo well past its efficiency range and/or have a poor intercooler, your timing requirements will change a lot. If you don't have good data from your injectors and have them scaled properly getting the tune nailed down for all weather conditions can be difficult.

If you really want to get down to it, the timing requirements on the dyno aren't anywhere near where any car I've ever had wants at the track, even with the exact same weather conditions. With experience you will learn what the car likes.

You can still do plenty of good work on the dyne testing parts and charting changes, which is all I've ever found the dyno useful for. It doesn't get me a competitive tune for the track.