What kind of psi should I be seeing in cold weather (-10º, 20F)? My car usually hits a max of 10-11psi in warm weather but the other day I hit 13psi on the 1st turbo and fuel cut on the 2nd when driving in the cold. The only mods to the car are DP and highflow cat.

 

You should get a boost controller, and adjust it for colder weather. 11psi max.

 

It's normal to see your peak boost go up a little in cold weather. The turbo compressors operate more efficiently on cold intake air.

I'd take it easy in the real cold weather and not push full boost. On some cars with shaky tuning, the cold weather boosting is the straw that broke the camel's back.

 

Sorry, double post. Damn computer!!

 

Guess I'm just wondering what kind of increase is normal in 20F... the intercooler piping was ice cold, but would this be enough for a 2-3 psi increase or is something wrong with the car.

 

Sure it can...I noticed a 2psi increase in boost just by slapping on a cold air intake box vs. K&N's just sitting in the engine bay. Of course I turned it down with my MBC.

 

I seem to remember seeing something that said to expect a change of approx 1 PSI for every ten degrees (C) ambient temperature difference.

 

My 99twins are coming up so hard in the cold that im seeing 15psi(especially in the primary turbo).
I just have to lower my "vent learn" settings.

 

very cold weather = nature's NOS

 

i love cool weather, it keeps my car happy..

 

hey man,

its normal. I have a california FD, that I drove to michigan while going to grad school there. The boost creep was more than ever in the winter months. I think thats why my LIM gave out. I was seeing 13's and fuel cuts all the time when the weather was below freezing. I recommend installing a manual boost controller for now before upgrading to a real controller. You can do this by splicing a valve into the wastegate control line and removing the existing pill. this will allow you to reduce max boost. Remember: opening the valve reduces boost!! Make sure you have it open when you start tuning.

-hrach