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

[short4stuff]

At my dads work .. they have a book there for pistons and stuff, and well it shows the 12:1 for the 200s but it dont say for the 200x... my dad thinks it is different, but aint it the same? .... Somebody let me know... also should I go with the 12:1 or the 10.25:1 ? ...

[Studytime]

You could try a search- you will find plenty of info on this topic.

Studytime

[TimSr]

You can check applications at www.wiseco.com

[deathman53]

if you want to use only race gas, a 12:1 is fine, my advice get a 10.25:1, race gas gets expensive fast

[thefox]

if you want to use only race gas, a 12:1 is fine, my advice get a 10.25:1, race gas gets expensive fast

I agree, go with the 10.25:1. Oh, yes the 200s piston will fit a 200x.

[83185s]

yea its the same thing but id put in a 10.25 before u go to 12...not good on the leg ..lol..also yea the gas gets expensive fast..if your cylinder is to big lemme know i got a 200s and a 185s cylinder lyin around (inside) no rust..

[MTS]

same piston, the 12:1 really wakes up the 200, my friend runs his on 97 octane with some nitro methane added, the nitro methane you can get at a hobby shop, they use it for model air planes works fine in his bike he just adds a little bit to a full tank...hell it would prolly run fine on just the 97 octane...

[Kintore]

Isnt nitro methane real expensive? and I bet it wakes up the 200, my friend has a high compresssion piston in his blaster and it goes!

[Pistonhead]

I've got a 2-stroke weed-whacker, one time I accidentaly put a whole container of stp octane booster into it's little tank (before I would have known better). Man, it ran amazingly fast, but it would run solid for 1/2 hour then it would overheat big time and I'd have to let it sit for another 1/2 hour till I could use it again.

[Studytime]

Isnt nitro methane real expensive? and I bet it wakes up the 200, my friend has a high compresssion piston in his blaster and it goes!

would wake it up? From what I've read nitromethane only has around 1/4 of the chemical energy of premium gasonline (Btu/lb). I'd rather just run premium with some zylene or toluene added to it if I still had preignition problems on 93 octane.

Pure octane boost in a weedwacker accidentally? Hmmm... I would have bet it would not have even ran. IF you put too high of an octane fuel in a low compression engine then you're going to need A LOT of spark advance. Without the increased spark advance you'll be gaining zero of convention fuel.

I'm scratching my head on that one. A story that starts with "accidentally put ..." raises suspicion. Describe to me what "it ran amazingly fast" means.

Studytime

[90nut]

so is a 12:1 piston to high to be running in a 200x on pump gas(97 octane)? I got one for my 200x because the guy said that it was a direct replacement for my 200x. Well I now know different. Someone else said that it would be impossible to tune and that I would break the kicker gears. I dont know if any of this is true though I just want a second opinion. thanks

[Howdy]

It's not impossible to tune. Not that easy but possible.

Yes, a 12:1 piston would cause more stress on kicker gears. These kick starter gears are known to break under normal usage with a stock piston. So he is correct there.
Howdy

[MTS]

i dont know about the nitro methane stuff too much, my friend has a neighbour who is a bike mech and he said he could use that stuff, its not pure nitro it has some other stuff like toulean and ethnol and stuff in it i think....i dont know about this hard to tune crap, he barely even have to change the setting on his carb...from the stock piston

[90nut]

Howdy, would you personally use the 12:1 piston or would you get a stock compression ratio pistion? I already have the 12:1 piston but if it is going to cause me alot of trouble I will just forget about it and buy the stock compression piston.

[Howdy]

I had a 12:1 in a 350x I had years ago ( it got stolen ). It caused me a lot of agrivation. Hard starting, cost of fuel ( you can't run cheap stuff and get it to run good ), carb adjustments, ect. Using a 12:1 piston you could tell the power difference, but to me it wasn't worth the agrivation.

Now I don't use anything more than a 10.5:1 for any of my machines.
Howdy

[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