HarleyTechTalk

I'm going to run CP flat tops in my 103" build. I have everything I need, but won't be starting the build until next weekend. I wanted to get a jump on checking the ring end gap. My problem is, I don't know which of the two heavier rings is the top ring. One is darker in color than the other and has a dot on one side. I know the dot goes up, but I'm not sure if this is the top ring or 2nd ring. The other heavier ring is lighter in color with no dot or bevel from what I can see. CP's instructions are not clear on which ring is top and 2nd.

I know I can just call the place I got them from on Monday, but was hoping to get an answer today if possible.

Thanks in advance for any help.

Zach

I just got done installing my rings.  My top ring had no dot or bevel.  My middle ring had a dot on one side and a bevel on the other side; I installed it with the dot up and bevel down.  When you install your rings on the pistons, start with the oil rings first, then the second ring, and then the top ring.  It was easier for me to do it that way.  Hope this helps.  Later, Calvin.

Calvin - Are you using CP pistons?

After posting this, I decided to check the end gap on all the rings regardless of knowing which was the top or 2nd. This is what I found:

Black ring with dot gap = .024
Silver ring w/ no mark gap = .019

The recommended gap per CP is:

Top ring = bore x .005 = .0194 (my bore is actually 3.88)
2nd ring = bore x .006 = .0232

So based on my measurements of my rings, I'm putting the silver ring on top and the black ring with the dot in the middle (dot side up)

Any holes in that logic?

Thanks for the reply Calvin

Zach

Well not sure I do it by gap but you've got it right. The top is usually molly filled and shiny. The second is used as an oil scapper so it has a slight taper on the outside edge which makes it directional. I've yet to see an install directions where they say put the dot down..  Max

If there is a dot it goes up.  Never seen one with the dot down either.  The top ring is more than likely a moly ring.  Look at the rings from the side.  One should have a shiny face, thats the top ring.

Good Luck,
J

Zach, Sorry for taking so long to reply.  I did not use CP pistons.  I used SE Cast High Compression pistons.  Sorry if I caused confusion.  Good luck, Calvin.

Thanks for all the help everyone. I got it sorted out and am good to go. The top ring is the lighter colored ring with the "finished" edge. It appears to have no bevel on it. The black ring with the dot does have a bevel on the opposite side of the dot. Rings are on both pistons. Thursday is tear down day, and this thing should make noise by Sunday. I'm working on it in between a bunch of other holiday stuff, otherwise it wouldn't take so long.

Thanks again,
Zach

Cool deal!  Let us know how it turns out!  Later, Calvin.  PS what are the rest of the build details?

I'm doing a Head Quarters 103 ST kit. Full HQ head work, HQ575 cams, stock TB, Bassani Road Rage, SE Heavy Breather, TP Pro Vent rocker boxes, VP-92T, SE clutch spring, SERT. Hoping for 110/115. I've got a really good SERT tuner (Latus Motors) local so I'm hoping to get everything it has out of it.

Will post results in the dyno tuning section when it's done, although if the base map I got from another member feels good, I may wait to spring to get it on the dyno.

Zach