I've got one rod that came back from the machinist with the dot on the piston facing the back. He told me that he didn't find anything stating an offset and it would be ok. Is the wrist pin dead center or is it off set. I know the dot goes to the front but does it matter. If they are congruent mirrored image from the pin ill leave it cause I've finally got a weekend to rebuild it and hate to postpone the build. Much thanks.

 

Both sides are the and only you will know that one dot is facing towards the back

 

Cool man. Just what I needed to hear. Any idea where I could get a woodrift keyway for the front of the crank. I turned my core in with the timing cog on it and didn't receive one back in the regrind kit or in my new timing kit.

 

any of your auto parts stores should have one.

 

i wouldnt leave it like that IMO...theyre stamped to go in a certain way
because thats how gm wants it..otherwise they wouldnt put dots on them.

i think it has somthing to do with balancing and what-not.

 

What parts are you using? Stock or aftermarket? Valve reliefs?

 

Ahh they are either silvilite or federal mogul flat tops. They came in an engine tech lq9 rebuild kit I got off E-bay for 710$. The pistions were 300$ more than the lq4s kit. So I figured they would be good. They measure center but the weight distribution would be something. The woodrift key could not be found at autozone, advance or o'reighleys. Luckily I took the key out of the longer crank that came in the early lq4. It comes in the crank kit but aparently mine didn't. I'll need one latter of the ls1 crank I plan to use the longer crank and install it in my jet boat project.

 

The dot is on the piston for a reason. The offset pin bore is slight and may
be difficult to see with the naked eye. It quiets piston slap at and near TDC
A competant machine shop should be able to heat/press it apart and not
break the piston....let cool then reinstall correctly. Be patient and do it right!

 

With the stock crank, it shouldn't matter. Just install the pistons with the valve reliefs and dots in the correct orientation, regardless of whether or not the rod is "backwards".

Now if you were using an aftermarket crank, it would be a different story.

 

Federal Mogule pistons are gonna most likely be "Sealed Power" brand pistons and will have an S echted into the friction coating on the skirts .