Don Terrill’s Speed-Talk

Does anyone here have any experience with the Keith black "icon" line of forged pistons? I spent the morning measuring mine, got everything logged, then moved on to the oil ring support rails.....(the pin protrudes into the oil ring groove).....after I got them all measured I noticed that not one of them have the dimple that goes into the void facing downward to keep the support ring from rotating. Is this normal for kieth black "icon" forged pistons? I assumed all support rings had a dimple or some anti-rotation method. These have nothing at all.

Call united engine (icon) if they don't have the dimple don't use them

I had some support rings with the dimple that were bent at the dimple causing the oil ring to bind which resulted in oil consumption. Keith at Total Seal sent me replacements with no dimple that are working fine.

Enigma wrote:Does anyone here have any experience with the Keith black "icon" line of forged pistons? I spent the morning measuring mine, got everything logged, then moved on to the oil ring support rails.....(the pin protrudes into the oil ring groove).....after I got them all measured I noticed that not one of them have the dimple that goes into the void facing downward to keep the support ring from rotating. Is this normal for kieth black "icon" forged pistons? I assumed all support rings had a dimple or some anti-rotation method. These have nothing at all.

If the support rail is correct for the groove you do not need a dimple the rail isn't going anywhere

I see pretty good indentions into the piston from the dimple. If there was no force acting on the rail it shouldn't move from where I install the dimple in the middle of the pin bore. For me there's no way I would install them without the dimple. The rail could spiral around and unscrew out of the groove.

Thanks a bunch for your opinions guys. I had contemplated dimpling them myself, but I'll cal uem this week and see if they just sent out a bad set or if they were designed that way. That was my concern as well, Robert. Unspiralling or chewing into the ledge created by the pin hole.

Wolfplace wrote:

Enigma wrote:Does anyone here have any experience with the Keith black "icon" line of forged pistons? I spent the morning measuring mine, got everything logged, then moved on to the oil ring support rails.....(the pin protrudes into the oil ring groove).....after I got them all measured I noticed that not one of them have the dimple that goes into the void facing downward to keep the support ring from rotating. Is this normal for kieth black "icon" forged pistons? I assumed all support rings had a dimple or some anti-rotation method. These have nothing at all.

If the support rail is correct for the groove you do not need a dimple the rail isn't going anywhere

I haven't test fit them yet, but by the measurements, they should fit snuggly in the groove with around a .050 gap, or thereabouts. You think they'll grip the back of the groove enough to keep them from rotating, Mr Lewis?

Sometimes asking the manufacturer still doesn't provide the correct answer. There is one major maufacturer that everyone here uses that puts the wrong rail in some of their pistons. The radial thickness is wrong leaving the od of the rail a good bit smaller than the bore. It's very difficult to install the rings as they tend to twist and come out of the ring groove during installation.

We ran them for a long time, before they had dimples. Prick the center of the piston at the gap, with a spring loaded center punch, they wont move then.TB

Enigma wrote:

Wolfplace wrote:

Enigma wrote:Does anyone here have any experience with the Keith black "icon" line of forged pistons? I spent the morning measuring mine, got everything logged, then moved on to the oil ring support rails.....(the pin protrudes into the oil ring groove).....after I got them all measured I noticed that not one of them have the dimple that goes into the void facing downward to keep the support ring from rotating. Is this normal for kieth black "icon" forged pistons? I assumed all support rings had a dimple or some anti-rotation method. These have nothing at all.

If the support rail is correct for the groove you do not need a dimple the rail isn't going anywhere

I haven't test fit them yet, but by the measurements, they should fit snuggly in the groove with around a .050 gap, or thereabouts. You think they'll grip the back of the groove enough to keep them from rotating, Mr Lewis?

I don't have any experience with the ICON piston with their rail so I am not going to say it's the best plan,
I would recommend that you call & ask them if they want a dimple if you are at all unsure

Myself,
While I agree that having the dimple appears to be the better option considering it is a positive device to keep the rail from moving,,,

If the support fits the groove tightly & the ends are still nice & sharp like they normally come I do not feel it is necessary & do not have a problem running without a dimple.
At least this has been my experience & when I asked either Keith or Kevin at Total seal the same question years ago when I ran into rails without the dimple they told me the same thing with their support rails.

I think where you may run into a problem is getting a rail that "fits" multiple bore sizes,,,r something said to fit from say 4.500 to 4.560
They are real tight at 4.560,,, not so much at 4.500

I suppose I should add that we finish the bores pretty smooth too. If you finish them with a high crosshatch angle &/or on the rough side I would assume this would tend to cause more rotational loading to all the rings & in turn the rail, especially if it wasn't gripping the piston real good or did not have a positive stop.
=====

Tony
I like your idea,,,,
Where do you put the punch mark to locate the gap?
In the middle of the bottom ring groove?

Bottom of the ring groove, if the spacer tried to rotate. it would give it a place for the sharpe edge to bite into. NEVER had one move after doing this.TB

Tony B wrote:Bottom of the ring groove, if the spacer tried to rotate. it would give it a place for the sharpe edge to bite into. NEVER had one move after doing this.TB

Thanks

Tony B wrote:Bottom of the ring groove, if the spacer tried to rotate. it would give it a place for the sharpe edge to bite into. NEVER had one move after doing this.TB

I like Tony have never had one move with this approach. Fit is critical!