Piston Slap? Ridges on bottoms of cylinders (pics and vids) Help!!

[speedfreak426]

hey are those pistons aftermarket? i always check for pistons clearance when i am building a motor, and when i take the head off it always looks like it, but again with aftermarket pistons at 0.035 inches clearence.

Looks like stock pistons to me

 

[7MGTEsup]

Looks to me like the engine has been re bored and the person who did it stopped where the piston stops and didn't go right the way to the bottom of the cylinder. Or thats the only explination I can think of.....

 

[speedfreak426]

I'm not really sure, it's not really a hard ridge, there is a ridge there, but it is smooth to the touch.... It does not catch your fingernail while running over it. Hard to explain. There is almost no ridge at the tops of the cyl's

:1zhelp:

 

[Mk3runner]

thats odd stuff. if money allows it its a excuse to bore over.. I'd just go over the engine and do it by your own hands. you know, no mistakes then unless you screw up.

 

[speedfreak426]

just to update this....

Took it to a race machine shop...
they checked it and told me it was just a .003" step, and that i could get away with just a hone job. They said it was probably just caused by "excessive high rpm operation"

but I decided to take it a lil further to be safe... and for some future high 10second 1/4's



Engine is getting....
-Bore .020" over
-Wiseco coated forged pistons
-ARP hardware everywhere
-Rods resized
-Polishing crankshaft journals
-Oil pump driveshaft bushings after hot tanking
-Shimmed oil pump
-Skim block surface
-Skim head surface
-Cometic MHG


Then once I finish paying for all of that goodness.... going to go with the LEXafm/550cc combo with a AFPR and an upgraded(57 or 60 trim, idk yet) CT26.