Technically there will be a difference due to denser air at PIR(Portland International Raceway), which I think is about 70 feet above mean sea level. Montana?? Probably a lot higher.
Don't know about PIR policies about racing, but I recall a friend driving something like Sportsman class VW Golf/Rabbits there. It was a sanctioned race with multiple contestants and it cost money to enter. I would bet at least they have a safety inspection.
One thing maybe to watch for, Portland streets are wet more than half the year so drive accordingly. I would assume if you have the traction control that would help. Being from Montana, you probably have plenty of experience on ice. Portland gets Ice or snow maybe 1/3 of the years I lived there. Watch out for Bozo festivals when it gets icy, lots of clowns on the road doing their thing. I have seen them stop their cars on the freeway right in the middle of traffic and just leave even though traffic was still moving although slowly in a snowstorm.
Buy gas in Vancouver if you can, it is often much cheaper and you can pump it yourself.
You will find GI Joes to be a pretty good autoparts and sporting goods "superstore".
Good Luck,
Jim Henderson
