Ring Gap Position, JONH MARHALES AND JSRE

[gringo]

Hey will this work? I have top pin pistons and have the ring gap set to line up with the centre boost port which is margianly wider than the two adjacent side boost ports. The top and bottom of the centre boost port is nicely radised so ring catching should not be an issue. But has anyone tried this and will it live well at 7200 rpm. i figure that the centre port runs cooler than the side ports. Any thoughts please.

[CharlieB53]

My 2 cents

I understood that we wanted to keep the gap away from the centerline of the thrust surfaces. Ideally, 45 degrees or more.

[us1]

You can run the gap in the small boost port. Thats where I like to put it. The large boost port is too big and will catch the ring tips. Mercury runs the gap in the small boost port on all Promax 2.5s and on all 2.4 motors.

[gringo]

Its already running, no drama yet still running in. Any one else tried this? How will it go after break in? Ill pull it down if it is a no no , could not bear another ring / piston drama. Chris

[us1]

I will come apart with RPM. The ring tips bulge into the port and will ware the cylinder wall at the top of the port eventually breaking off the ring.

[gringo]

Thanks John, thats all i needed to hear. We have a very well set up machine shop and hi tech welding gear. I will pull it down tonight and go the same routine in the small bost port at 45d which happens to be where merc and you put em. I will be able to machine up a custom plug to fill the dead hole then weld it in place at the crown which should stoop leak through. I should try to stop "re inventing the wheel". My old dad used to say to me as a kid "if you want to win races, copy the winning guy and then drive like you stole it". Thanks, Chris

[us1]

Better safe than sorry. All my tests in that location were disastrous.