12:1 200s piston same as 200x? ..

[vartiak15]

by running higher octane do u get a big difference than just pump gas? mine runs gread and starts first kick and i got a 12.1 compression. its a 200x. 110 main jet.

[83185s]

it starts easier with higher octane and runs a little hotter..but if you use low octane trailprotrailpro more than likely gonna burn up the piston..just becuase it burns slower doesnt mean it leaves the engine faster..higher octane leaves quickly although it burns hotter..do u see what im sayin?

[OldSchoolin86]

it starts easier with higher octane and runs a little hotter..but if you use low octane trailprotrailpro more than likely gonna burn up the piston..just becuase it burns slower doesnt mean it leaves the engine faster..higher octane leaves quickly although it burns hotter..do u see what im sayin?

This statement makes me think of that part in Billy Madison where the principal says eveyone one is now dumber.
Nothing in this post is good for octain information.

Sorry but it's true

[vartiak15]

help me out here oldschoolin

[PlatinumDogg]

it starts easier with higher octane and runs a little hotter..but if you use low octane trailprotrailpro more than likely gonna burn up the piston..just becuase it burns slower doesnt mean it leaves the engine faster..higher octane leaves quickly although it burns hotter..do u see what im sayin?

I thought that higher octane made it run cooler.. I.E. running a high compression piston would create more heat, thus running high octane would make it run cooler. Correct me if im wrong.

[Studytime]

it starts easier with higher octane and runs a little hotter..but if you use low octane trailprotrailpro more than likely gonna burn up the piston..just becuase it burns slower doesnt mean it leaves the engine faster..higher octane leaves quickly although it burns hotter..do u see what im sayin?

Actually higher octane shouldn't make it start easier or run hotter. Do automotive engines that only require 87 octane start poorer and run cooler than those requiring 93 octane? No. However a high compression engine will run hotter which is where some of your ideas may be stemming from.

I know this is just review for a lot of you guys, but the "octane" rating is as already stated just a degree of anti-knock. When ever you rapidly expand a gas it cools off. This is how a home A/C works- pressurized gas expands through an orifice or expansion valve. The converse also holds true, when you compress a gas it heats up. The compression ratio is the ratio of cylinder volume + combustion chamber volume TO combustion chamber volume. A dome piston decreases the amount of combustion chamber volume by sticking up higher from the face of the piston. This dome (as opposed to a flat top) causes less combustion space and as a result a higher ratio of cylinder volume + combustion space : combustion space.

So, with an increased compression ratio more compression will take place, and this is what you want for engergy release- high heat and high pressure. So, we have our high pressure, but also have additional heat from the increased amount of combustion. So, as the engine thumps along the piston travels up and down in the bore. As the piston travels UP on the combustion stroke the cylinder temperature begins to rise. As the temperature rises the pressurized intake mixture will prematurely start burning before the piston reaches the top of the compression stroke this creates engine chaos. The inertia of the rotatin assembly has to over come the pressure the cylinder now sees. This high pressure as a result of the chemical reaction of combustion will cause the engine to undue itself. These pressures at the wrong time will cause mechanical failure.

To combat this problem you need a fuel that can take the increased temperatures experienced during the compression stroke without said fuel preigniting. This slower burning fuel will be one with a higher octane rating.

Now, more BTU's per mass of fuel will not necessarily be given off. This is the engergy that heat/power is measured in. A fuel that gives off more heat during combustion will give more power, but it will also cause your engine to run hotter.

I haven't read all of this, but here is some data with the heat values of some fuels given.

http://chapman.sprl.db.erau.edu/~lazersos/fuel.html

Studytime

[Studytime]

Oh, let me just add that the extra power you're looking for will come from the INCREASED COMPRESSION not the fuel it is ran on. Again, it's from the extra compression. This increases efficiency/power.

The higher octane fuel is a consequence mandated by the higher heats of compression.

(This statement made under the assumption that both hypothetical engines are utilizing the correct spark advance)

Studytime

[Studytime]

Additionally, these may be found to be benificial reads;

http://www.tuninglinx.com/html/a_octane_r.html

http://www.motorcycle.com/mo/mcnuts/fuelron.html

The knowledge picked up should be worth the time invested to read them.

Studytime