Might also have been (in addition to the gearing) that your dad’s Model T engine had all of 20 horsepower. The cool news is that it was a flex-fuel vehicle! The Model T engine could operate on kerosene or alcohol as well as gasoline! 
Sure, the compression ratio was about 4.5 to 1. Also the hp was 22.
A lot of old farm tractors were designed to burn either gasoline or kerosene, but they had extremely low compression ratios, in the order of 4 to 1 or so and also the intake manifold was heated by the exhaust to vaporize the kerosene so it would burn. These had to be started on gasoline and then after the engine was warmed up the carb was switched to kerosene. There was a separate small tank to hold the starting gasoline and a fuel-gas-off valve to control which tank was being used.
The float bowl also had a drain in case you forgot to switch back to gasoline a few minutes before engine shutdown and were stuck trying to start it with a float bowl full of kerosene the next time you used the tractor.
After cat cracking was developed by refineries, the price advantage of kerosene largely disappeared and most people quit bothering with using kerosene and just ran the engines on white or regular gas. Usually white gas because it could be bought in bulk tax free for non highway use from major distributors.
The exhaust manifold acted as a stove to preheat air entering the carburetor so that kerosene would vaporize and burn. You likely still had to get it started on gasoline first or heat the intake manifold with a torch before starting on kerosene. I suspect that a lot of the people who used kerosene mixed a little gasoline with it to make starting easier.
With ethanol, you would have to adjust the mixture screws on the carburetor to suit the air fuel mixture ethanol needs to burn. On cool days, ethanol also needs to be primed with gasoline or have some gasoline blended with it in order for the engine to easily start. That’s one of the reasons they sell E-85 and not E-100 today. So engines will start in cold weather.
I just drove my 6 cyl. 2009 Jeep Grand Cherokee with 144,000 miles on it to the top of Mt. Evans (14,265’) with no problems.Regular gas. No car built in the last 30 years should have a problem with altitude other than some loss of performance due to less oxygen. There is something wrong with the car, period.
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Very true.
Just for fun, I calculated how much less O2 there is at 15k feet. That is 4570 m
Pressure changes from 100 kPa to about 56 kPa. Assuming the temperature is constant, the amount of oxygen would change in proportion, that is, 56/100 or 56%. That is more than half the available O2, and thus more than half the power. With high HP engines, that would be barely noticeable.
Change due to temperature would be smaller. 50ºF change would cause about a 14% change in density, with colder temps causing an increase in density, offsetting to some extent the altitude change.
(both according to charts found on the internet… accuracy unknown)
the 09 4.0 6 cyl motor is a bit different than the 2015 V6. they did change out the 3.6 in 2015 for a VVT version. i have seen both mentioned when talking about 2015 models.he is coming home for labor day so i can look under hood and see if it is the VVT model. probably not. he says mileage kinda bites and it was no better on the highway when he came home last yr at xmas. it is a brick for styling.
Sorry, what does this mean?
2004 was the last year the 4.0 L engine was used in the Grand Cherokee, 2006 for the Wrangler. There were 5 different engines available in the 2009 Grand Cherokee but none of them are related to the 3.6 L.
All Pentastar 3.6 L engines have variable valve timing.
Yes electronically managed fuel-injected cars adjust for altitude, but that doesn’t mean they have the same power. A normally aspirated car loses about 3.5% per thousand feet, so a 200hp car at 10,000 ft is effectively 130hp, and at 14,000+ ft it’s only 102 hp!! Just because it’s not sputtering and smoking like an old carbureted car does not mean it isn’t falling all over itself trying to come up with some power. Pack full your normally aspirated baby and head up Pikes Peak and you’re going to have trouble moving at any kind of speed and may also encounter overheating problems. If there are any issues with the vehicle, being down 35 to 49% on power has a strong tendency to bring that out. It could have been any number of things. If you tell a mechanic the symptoms and he says he knows what’s wrong without even looking at the car, RUN the other way as quickly as possible. What appear to be the same symptoms can be caused by a number of different things. The only way to find out is to dig into the car/motor. Needless to say this warning strongly applies to people on the internet who profess to have answers sight unseen. The person who said they make Jeeps for high altitude was incorrect. They don’t make any car specifically for high altitude. There aren’t enough of us humans at high altitude for them to bother. The generic answer is a turbocharger or supercharger. These pressurize the intake air, which minimizes or eliminates the high altitude problems. That’s why I drive a Subaru Legacy GT turbo, 250 horsepower more or less from here to the Moon. People professing to know something should have to state their qualifications. I live in Denver, I’m in the mountains all the time, I have years of shop experience, I build hot rod motors & race car frames for a hobby and I have a Masters in physics. Oh yes, I used to live in Cascade (on the side of Pikes Peak) and was involved with the Pikes Peak Hill Climb, so I know about driving regular cars up it, turbo cars, race cars, open wheels etc. Whatchoo got?
Relax, this is a forum. You don’t have to qualify to be here. There are some very good people who post here that have excellent knowledge. The other part is that ( if it is on the internet it must be true ) which means I could claim to be a rocket scientist or is it rocket surgeon as another member likes to use that term.
People don’t build frames and engines for a hobby. You build them either because you need them or you are selling them, which makes it a business not a hobby. I mean what do you do, put a freshly built high performance engine on the shelf next to the model 1969 Chevelle 396 you put together last week. You must have a lot f room to store the engines and frames you build as a hobby. I’m glad my hobby is repairing and collecting old watches and pocket watches. They are a lot easier to store. And living in Denver or on the side of a hill does not make you any more of an expert on altitude, than living near Wash. D.C. Makes me an expert on politics.
Sure they do, lots of them. I do and so do most of my friends. We’re not in it to make money just feed our habit. I used to have lots of project cars laying around. Motors too. I almost always had way more into projects than they could be sold for. When i did liquidate or trade, if i broke even it was cause for celebration. People have all kinds of hobbies that drain cash. Fun isn’t free most of the time. What’s your hobby (ies) and do you strive to make money on them?
Maybe it is just our definition of “hobby” is different. To me a hobby is something I do for myself, such as model building, or collecting and repairing watches. I just don’t have the space to build and/or collect car frames or engines. I have not sold/traded any of my watches or models. Maybe its all just semantics.
Back to turbocharging. I disagree with Kellywood55’s comments. But I’m not an expert, so I could be wrong. Comments?
Turbo charging at sea level is used to increase HP without increasing displacement. It does this by forcing more air into the combustion chamber than atmospheric pressure would allow, thus increasing the amount of fuel-air mixture that explodes.
Now when you move up in altitude, to, say 10k feet, the turbo can’t span any faster, and because of the lower pressure, cannot pump as much air into the engine as it could at lower altitudes. So the maximum engine HP will decrease at altitude just as a non-turbo engine would.
However, if the computer is good enough, ir may turn on the turbo at a different set of conditions than it would at low altitude, and produce an increase in power at lower demand levels. don’t know that this makes sense.
Thought I read the jeep 3.6 had major changes in 2015/2016? Specs said it basically was all new. Except for displacement. '15 had 258hp and '16 had 305hp? Both may have vvt but there were many other changes.
It insinuates the jeep has the aerodynamics of a brick.
If it costs you money, it’s a hobby.
If it makes you money, it’s a profession.
One of the effects of high altitude is that the low density air does not cool the engine as well as sea level air does. World War II bombers had a lot of trouble with engines overheating when flying at 30,000 ft to stay out of the range of FLAK guns. I even notice this when snow skiing at resorts that are 10,000 ft above sea level. When it’s 20 degrees outside, I can dress a lot lighter in the mountains than I need to for a 20 degree day at sea level. I have even seen electric motors that had altitude limits stated on the nameplate for full load operation. Go above a certain altitude and you have to run it at a lower load.
Overheated engines will detonate more easily than cool engines. When riding air cooled motorcycles on 105 degree days, and I’m stuck in crawling stop and go traffic, I have to be really gentle on the throttle for the first couple of miles after the traffic finally moves or the engine will knock.
The “Appeal to Authority” logic fallacy:
Using an authority as evidence in your argument when the authority is not really an authority on the facts relevant to the argument. As the audience, allowing an irrelevant authority to add credibility to the claim being made.
Examples:
“I’m a world class violinist, so I’m obviously qualified to repair violins.”
“I have been flying airplanes for over 30 years and have a multi engine and instrument rating, so I’m certainly qualified to overhaul the plane’s engines”
Well, no, the world’s best pilot has no more business under the cowl than the world’s best mechanic has flying the airplane.
My experience in driving at high altitude locations is that my car gets amazing gas mileage in that thin air.