I was just wondering what the compression ratio was on all the outlanders?

A few points above 10? 10.2, 10.5 10.8???

All the other brands use something like 9.2:1 or 9.5:1 compression, but none above 10:1


Is that why the outlanders make more power? they run 1.0 more compression or something? or is it also cuz of the cams, carbs/efi, and head designs?


And another question, the most important one.

WHAT IS THE POINT OF RUNNING UNDER 10:1 COMPRESSION????
MY DS250 RUNS AT 10.6:1 COMRPESSION AND IT CAN STILL RUN ON 87 OCTANE. compression makes power, and everyone, even extremely rural areas have access to 87 octane, probably 89 and 91 too....

I know not everyone can get access to, (or afford) 115octane gas for 14.5:1 compression engines, but why not just come in 10.5:1 compression stock?

thinking out loud

 

Compression causes heat.

Higher octane fuel doesn't mean it is more powerful it only means that additives have been added to make the gas burn slower and not to ignite from a high compression but to wait for the spark.

Lower octane fuel is more explosive and will ignite and burn faster. You should use the lowest octane that your engine can use without getting pre-ignition (spark-knock). If you use higher octane then carbon deposits will be left behind and that will raise the compression so that you may have to continue to use a higher octane until the carbon is removed.

The reason a higher octane fuel cost more is because of the additives and not because it is a higher quality of gas. Just like diesel fuel needs a very high compression to burn. Actually the higher the octane the lower the quality of gas but the higher the resistance to ignite from high compression.

 

i know that hi octane is worse than lower octane powerwise... but compression makes power doesnt it?

Im sure that heating still isnt an issue yet (for aircooled engines) even at 11:1 compression

What i think is stupid is that low 9.2:1 compression when they could be using 10.2:1 compression and still run on 87 octane which everyone already uses anyways with any engine that doesnt need 93 or 100 octane

Why not try to squeeze an extra 2hp outof those engines? its free, the buyers will still use the same gas... and for the heat, well they can wear pants for once (which they should anyways just in case they roll or flip)

 

I don't know, maybe they feel that the lower compression is easier on the valves and cylinder-head etc. and for the long-life of the engine the extra couple hp isn't worth it. It is better to cruise an engine then to have it running at peak all the time. It makes sense to me. For me I would opt for a lower compression engine and have it last longer, and be more reliable, and sacrifice a couple hp. If I need more hp then use other methods or get a bigger motor.

 

<div class="FTQUOTE"><begin quote>WHAT IS THE POINT OF RUNNING UNDER 10:1 COMPRESSION???? </end quote></div>
I've wondered about that for years. The only thing I could come up with is maybe the manufactures figured that the quality of gas might degrade some more in the future.
My friend had a 426 wedge car. This thing came from the factory with I believe 13 to 1 from the factory!!!!!! Try running that with todays pump gas.
Fast forward to the year 2020. We may have 75, 77 and 80 octane for the good stuff in that year?
That and reliability does go up a touch with lower compression.
Good question though.