checking piston wash

[wasatchcomm]

what am i looking for when checking the piston wash.
i hear/see the wash is different for flat top pistons vs domed pistons
i have m8 with flat top pistons, what is good and what is bad, anyone have a pic of a lean, perfect, rich wash?
thanks in advance

 

[boone]

I am also interested.

Thanks,
Boone

 

[diggerdown]

3/8" to 1/2"deep half moons at the intake ports. 1/2" is getting rich.

 

[TheBreeze]

This is pretty close, maybe a hair lean for some. M8 piston. I guess the domed pistons snow much more wash compared to flat tops given equal amounts of fuel.

 

[shawkins]

Is this out of a trubo? I have always been told you can't read piston wash on a turbo. That's pic shows how I like to run my NA sleds. Just wanted to make sure this was on a turbo. Thanks

 

[TheBreeze]

That piston is out of non turbo M8. Sorry! Didnt see this was the turbo section till after I posted. I don't know a dang thing about wash on a turbo.

 

[BigAir]

Do turbos normally show the same wash as n/a sleds?

 

[shawkins]

My last turbo I had I could not read the piston wash. I have not tried to look at my M8 yet. Wish it was a little easier to look inside the cylinders and I would look.

 

[boone]

Not to sound stupid but if the picture above is ideal, what does too rich and too lean look like? It is my first time really tuning a sled myself. I am running a non turbo M1000 so sorry for hyjacking the thread but I thought it would be better to ask here than to post a new thread.

Thanks,
Boone

 

[wasatchcomm]

My last turbo I had I could not read the piston wash.

thats what im wondering, i pulled my pipes and plugs today, i peered in the plug holes and the tops of the pistons look clean and new.
no balck marks or anything for that matter.
ive also heard you need to read the wash after being wot and quickly shutting the motor off, which would only be possible on the mountain...
i dont understand this, i would think the wash whether lean or rich would collect and show on the pistons.
my sled was brand new when i put the turbo on, it now has a little over 100miles on it now, i figured if i waited for some miles i could get a feel for the wash.
but i dont see anything...
also a flat top piston wash will be different from a domed shaped piston, from what ive read.
keep in mind im running avgas, not sure if that will matter or not.
a pic of a lean or rich piston on avgas would be great. prefferably an m8 with boost.
anyone?

 

[wasatchcomm]

3/8" to 1/2"deep half moons at the intake ports. 1/2" is getting rich.

thanks for the reply!!!!

are you talking for a flat top piston on boost?
any pics i could see?
thanks again...

 

[Johnmaster]

Good thread, I have often wondered this myself. I assume if you have a well used motor and the piston tops are still shiny that you are way too rich. Anyone know how long it takes to build up enough burn on crud to be able to tell?

 

[wasatchcomm]

Good thread, I have often wondered this myself. I assume if you have a well used motor and the piston tops are still shiny that you are way too rich. Anyone know how long it takes to build up enough burn on crud to be able to tell?

im pretty sure im a little rich, especially in the low end, also with so little miles on the sled, i just may not be able to see any wash either way...
i will keep my egt's under 1200 and ride it, ill check the wash after a few hundred miles or so.