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Driving at extreme altitude

In a few weeks, I’m planning to drive to an elevation of about 15,200ft (outside of the US, of course) – I’m going to fly to a city near my destination and then rent a car. Unfortunately, the selection of rental cars at the airport I’m flying to is pretty minimal – and the only one that appears at all affordable is a Renault Clio with a 1.6L 4-cylinder engine.

So, this is a question for those of you who frequently drive compact cars at high elevations: would the Clio likely have the power to climb to that elevation? If you’ve ever driven a similar (sub)compact to the top of Pikes Peak or Mount Evans in Colorado, let me know how it went, as the difference in elevation isn’t huge.

The rule of thumb is about a 3% power loss for each 1000 feet of altitude and a small engine can make ascents a struggle at times.
With my Lincoln and the V-8 it’s not too bad but I’ve been to CO a number of times in 4 cylinder Subarus and SAABs (non-turbocharged) and they started getting a bit gutless around the 8000 foot mark. Independence Pass at 12000 feet was making me wonder if I’d make it over the top.
My Harley has also gotten a bit anemic at altitudes.

My feeling is that 1.6 Renault is going to be gasping and running hotter than normal. If you’re not familiar with the BBC show Top Gear you might check out the episode where they took 3 vehicles on a trip through South America. At the 17000 foot mark in Chile they called it quits and went back the way they came because of the lack of power in the vehicles and the coronaries they were about to suffer.

There’s a reason why many aircraft use turbo and superchargers; to compensate for that thin air at altitude.
Just my humble opinion and hope it helps. Good luck.

Thanks so much for the helpful comment! I had heard the 3% power loss rule before, but I didn’t have a good feel for how that would translate into on-the-ground performance for such a small engine.

I’ll take a look at that Top Gear episode. If they hit 17,000ft, any of the vehicles they used should be able to make it to the elevation I’m going for.

The vehicles the Top Gear guys used consisted of a Toyota Land Cruiser, Suzuki Samurai, and a Range Rover. The vehicles were still going at 17000 feet but had been pretty anemic for some time on the way up. They gave up with the statement that even if the vehicles could make it, they couldn’t.

I doubt there is an “interstate” type multiple lane highway at 15K feet. Likely you’ll be on a hard pack unpaved road so speed isn’t an issue. Most likely you’ll be renting a car with a stick shift, and you will need to use all the gears in a small low powered car. You’ll make it though you won’t be going very fast, but I don’t think speed is an issue anyway.

“would the Clio likely have the power to climb to that elevation?”

Of course it will! But if you’re the typical American used to econoboxes of today having the acceleration of sports cars of 40-50 years ago, you might get impatient.
The early VW Beetle with less than 40hp could climb to that elevation.

It’s like that Zen saying: everywhere is walking distance if you have the time.

I think the car will make it, thought it wouldn’t hurt to ask the rental agent. A couple of years ago I spent a month touring Northern India on a Royal Enfield Bullet loaded with about 250 pounds of rider and gear. The we made it over Khardung La, just over 17,000 ft, limited mostly to second gear. All kinds of vehicles were making the trip. There were plenty of Suzuki compacts and the staple of travel in that region the Mahindra Scorpio a small SUV with a non- turbo 110hp. There were a couple of bicyclists as well!

Unless you are familiar with how your body reacts to high altitudes, your concern should be the effect of the altitude on you. If you plan to land then immediately drive to 15,200 ft. I predict an unpleasant journey. Google “acute mountain sickness”. If prepared you will have a great trip.

http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0001190/

Any turbo diesel available to rent? That would be better, both for fuel costs and high altitude use.

The rental company may ask where you intend to go…I suspect they may lose interest in renting you a car when they learn your itinerary…But if trucks and buses navigate this road, the Renault should be able to do it too…You WILL want the damage insurance to cover things like tires and windshields…Be sure you understand how the deductible works…

A 1.6 4 cylinder engine which isn’t much smaller than the engine in my own car is going to be doing the little engine that could “I think I can, I think I can” up the mountain. My own car isn’t much of a mountain climber and I go above 8,000 feet with a steep incline and my car tends to groan a little. But if you’re going down the mountain, other drivers look out because little cars will fly down hill!

Well the laws of physics tell us that, all things equal, the big car and the little car will descend the mountain at the same rate. But if I’m in the little car, I’d be looking out for the other drivers and the runaway truck!

I’ve been at 11,500 with my Jeep (Hoosier Pass) and it kicked a** all the way up, but with somewhat of a performance decrease. No problem holding highway speeds at Eisenhower Tunnel (11,200 ft).

I understand high elevation to be a place where forced induction (supercharger/turbo) really shines–not knowing where the OP is traveling, I would use as an example a VW 2.0T versus 2.5…I imagine the 2.0T would be the better choice here.

I hope you have a wonderful time. Just want to say I agree with MTraveler, after having done that area late last year. Many people make that trip – it is beautiful and supposedly the world’s highest motorable road, and many kinds of cars make the trip. You’ll travel more slowly, but the scenery will be worth slowing down for. If your planned trip is where I think it is, the most dangerous part may be getting to the high-altitude road itself, because the drivers would be considered maniacal by US or Euro standards. The rental agency should be OK with your plans but it might be good to check with them.

FWIW, I live in a high altitude state and find many “sealevel-ers” coming here to climb a Fourteener (a peak higher than 14,000’) or two. The only ones who seem to enjoy it are the ones in excellent aerobic condition, and they generally do as well as most natives, although they gasp a little more. Aerobic fitness seems kind of like the human equivalent of turbocharging, so it might be good to get into good physical condition.

If you can rent a car with a turbo, it will help a lot to compensate for the thin air. At lower elevations, the turbo’s waste gate will spill extra pressure generated by the turbo out, depending on how it’s calibrated, to not ‘overboost’ the engine. At higher altitudes, it will just not pop open as soon and you will notice a lot less difference than on a non-turbo engine.