Hey all,

I took my head off to replace with a ported unit and wanted to get your opinions on this wear. My motor has ~600 miles on it, and the cylinders look like this. Is this normal? It looks like there's too much side loading on it. My built 2.0L was gapped on the loose side and after 5K miles didn't look nearly this bad.

.....this is after 600 miles of a proper break in and no boost, so it looks like it will eat itself in no time at all.

Cylinder #3:




Cylinder #2:

 

Thats not good! Coated pistons? What clearance?

 

Wiseco HD Pistons. Don't know clearances as they're built to the spec of the builder.

 

Just one cylinder or all 4?

 

Pictures above are cylinders 2 and 3. I'd be willing to bet it's on 1 and 4 as well, seeing as these two look almost exactly the same.

 

wow thats nasty looking....good thing you took the head off and caught this early.

 

My thoughts exactly...

 

Did my research. This wear, which is wear from the piston skirt, can apparently be caused by two things:

1) PTW Clearance is too tight or too loose
2) Bores are out of round (no torque plate)

If left untouched, this thing wouldn't have lasted very long..

Thank God I pulled the head.

 

arent the skirts on the hd weisco pistons black? maybe its just rubbing off?

 

I would venture to say it's a lot more than the piston coating, seeing as it's worn almost all of the way through the cross hatching.

 

A word from the builder to show that this wear is normal, I guess. Don't want people to get the wrong impression from MAP if there's not an issue:

"This wear pattern is very typical for the style of piston you have
in your engine. With your long rod configuration the piston skirts are very
short, which causes this type of wear as there in not as much support for
the skirt as there would be in a std. rod length engine. There is nothing
to be alarmed about and after seeing you broke it in per our instructions
you should have no problems with your engine. Let me know if you have any
other questions."


..I'd still like another opinion I think, as a LR is supposed to reduce side loading.

More pictures:

 

Those look like low spots where the rings arent scraping. That means oil will accumulate there and cause poor ring seal and detonation.

 

That's what I've heard from others as well...

What are my options at this point?

 

Check bore distortion and open the piston to wall up. If you can slide another 87mm in at what I consider normal piston to wall (for your eventual goals) you may be able to hone this back into shape if its not ovalled out. It doesnt appear to be, so you may be able to get away with that.

 

You also have to be sure to take you piston measurements from the correct place as the pistons are tapered and if you measure the wrong place, your PTW figures will be skewed.

Typically 1" up from the skirt is the proper place to measure