I don't know if this is a silly question but I drove down to LA for the weekend and I was going pretty fast throughout the whole trip, averaging about 90 mph, but mostly going at about 100 mph and at around 4000 RPM. In the end I ended up getting worse mileage but I didn't want the trip to take about 7 hours.

Anyways, I was just wondering about the harm this does to my subie. How bad is it really for my WRX to go at that high RPM for a prolonged period of time? Does it even do anything at all? Just being a little paranoid I guess but driving for 5-6 hours at 100 mph doesn't seem all that good for the subie.

 

Washington state to Indiana, cruise set at 90mph the whole way, with only 1 stop to sleep for 4 hours (not including short gas/eat stops). Not ONE issue the entire trip, or 5000 miles later.

Did you run the car hard??....yes

Damage???---I think as long as your fluids are good and you don't do this on a daily basis, there's nothing to be worried about.

 

Damn.. I get paranoid about driving at 80mph for extended periods. Did your temp gauge go up at all?

 

Do you have a boost gauge? I noticed (in my buddies wrx) when we took a trip to Las Vegas from Sacramento, that if you kept the RPM's below where boost is made, you get pretty decent gas mileage. If you up it to where you are getting a few pounds of boost, then the gas mileage is shot to hell.

And yeah, it probably isn't the best thing for the engine to be constantly at a moderately high RPM for so long.

 

Nope, my temp gauge was fine. I did notice that when I stopped at a gas station that my engine was idling pretty hard...it was shaking kinda hard...more than normal idle. I let it cool down for 5 mins before shutting it down which annoyed a lot of people cuz I was just sitting there with the engine on. lol...anyways, after the 5 mins the engine was normal again. But I was worried for a sec.

Hey Fundrrmr, how many miles is that? Cuz Sacramento to San Diego is only 500-600 miles.

 

I have alreday put 20000miles on my 04 wrx due to travel back and forth between San Jose and LA. Generally I drove at 100 miles/hour/ 4000 rpm. I only need one break at gas station for 3-4 mins. But before I stop I always slow down at 3000 rpm and keep driving for 5 mins. At the gas station I did not notice my suby shakes more like you said. Yes, the gas mileage was terrible.

I also have the same question as yours but a technician, I think his name is Steven, in Sierra Subaru told me that it will be ok. But he did not mentioed engine wearness.

But thank God that I don't travel anymore! It saves me a lot of gas and $$$.

 

I think it turned out to be 2300 miles each way. I had a month or so in Indiana before we drove the entire way back.

 

How old is the car?

 

me too!

 

If you change your oil according to the "severe service", your cooling system is maintained, and your tires are properly inflated with adequate tread, you should be no worse for wear. At 90-100 mph you have plenty of air moving around the engine for cooling. I'd start to worry about sustained speeds above 120 - at that kind of speed you can wind up in jail with your car impounded. And we all know how well tow truck driver's take care of other people's cars! LOL

Seroiusly, allowing the engine to cool down is a good idea after sustained high speed travel. A Valentine One is also a very good idea. FWIW, I have done dozens of trips from the Bay Area to Tahoe at speeds of 75-100, depending on traffic and road conditions - and this is while gaining a respectable amount of altitude. I think the car runs stronger now at 49K miles than it did at at 3K miles.

 

Stop and Go is harder on everything, IMO. At a constant speed, you have maximum airflow and fluid flow (coolant and oil) so everything is working at it's best.

Now, if you were averaging 5k RPM and above, I'd hesitate to say this still holds because of the high RPM.

 

Red Baron...

The car is an 03 WRX. She already has 22000 miles on it. The commutes from Elk Grove, UCDavis and CSUS are adding up miles like crazy.