O.K.-I searched for this, but couldn't find much - apologies if I missed an obvious thread. My MINI (MCS) will be living at 7000' and I'm wondering if an easier breathing air filter would help aspiration. I don't need loud, I just need good. Thanks.

 

An intake would be a great way to gain some performance in those high altitudes (along with a reduction pulley). Basically, anything that helps the engine breathe better is going to help performnce. You just have less to start out with since there's less air density a mile high.

 

Never driven a supercharged car at altitude but have driven a turbocharged car (VW TDi) and I was not aware of any diminished performance, though I know the performance had to be affected.

Surprisingly, turbocharged (and I believe supercharged) engines are affected quite a bit less at high elevations than naturally aspirated engines.

Before I did anything to the car, I'd drive it a while to see how the car/engine responds. 7000 feet is not much. I have driven several different cars over I-40 through AZ through Flagstaff and that's around 7700 feet and none of the cars (ranging from a 300+hp V8 to a 90hp turbocharged diesel) were affected.

Now going over the passes (some over 10,000 feet!) on I-70 in Colorado all my naturally aspirated cars suffered from the effects of altitude, but the VW diesel just didn't seem to be bothered. (And I don't even like to remember how a turbocharged Saab beat my naturally aspirated Porsche during an impromptu drag race in Colorado Springs...)

Anyhow, I stress though the VW TDi was turbocharged, not supercharged.

Most supercharged/turbocharged engines are designed to be over-pressurized at some point before engine redline and have ways of ensuring this overpressuration doesn't hurt the engine.

What happens at altitude is the overpressuration moves up the RPM scale a bit but because overpressuration still occurs this greaty diminishes the affects of altitude on the engine.

Drive the car. See how it performs. If you find you have to mod it for higher altitudes be careful you don't end up with a car that suffers when (if) you drop down to lower elevations.

I would find it hard to believe the stock intake is so restricted that you can gain any significant improvement in that area. What'll probably give you the most improvement is to overdrive the supercharger, to lower the point at which the engine is overboosted so at altitude the overboost is not moved as high in the RPM range as it would otherwise. However, this depends upon overboost protection that is bulletproof and I'm not familiar with the overboost protection the MCS has.

Remember too that overdriving the supercharger increases the parasitic load the engine sees (all the time) and driveability and gas mileage (and even engine longevity) could suffer.

Sincerely,

RockC.

 

Wow! Nice answer, RockC. Thanks. I think giving it a good bit of time (in Flagstaff, btw) is just the ticket.

 

I'll go along with RockC in that you need to figure out how much power the car has in stock form (and if any more is needed at altitude). As for intakes, you'll gain 5-10hp which will be slightly noticeable. The pulley is where most of the power is. A 15% pulley has been tried and tested without problems. Go over to Webb Motorsports and see what he has to say about performance mods.

 

I've always noticed a difference between Prescott and Phoenix with all my cars. The MCS suffers less than the others up here.
BTW: Welcome to NAM!

 

Well, I live near Tahoe... we go up there a bit. I notice the MINI doesn't perform as well at the higher elevation...