ring gap questions

Modular2v · Mar 12, 2006

well i have to pull my motor apart to flycut the pistons.....i ordered new piston rings for it and i forgot the 1st and 2nd compression ring gaps....Can anyone chime in? its a 331

txstang84 · Mar 12, 2006

what kind of pistons? most forged pistons use 0.004" per 1" of bore for N/A apps with the exception of KB-they have different req's for ring gap because of alloys and machining.

if using power adder open it up a couple thousandths...

in the past, I've usually put the top rings at 0.018", and the second ring at 0.016" , and yes that's for a 4.030" bore. Never had any issues with that...

jerryD · Mar 12, 2006

when you get your new rings in, it should come with instructions and a chart /w formulas for reccomended gaps per application. i would just follow what they suggest.

bluevenom867 · Mar 12, 2006

Secondary gap will be larger than the primary ring gap.

You can also call the piston manufacter and ask what they suggest.

Modular2v · Mar 13, 2006

thanks guys

Rick 91GT · Mar 13, 2006

Assuming you ordered them from probe they will most likely be a Perfect Circle, just follow there instructions for what ever application you will be using.

I know they have the top and second rings with the same gap on the sheet, gap the second .002-.004" WIDER

Jason 302 · Mar 13, 2006

It's interesting how gap recommendations have changed. My old man said years ago they always said to gap your top ring wider because it took more heat than the second and therefore expanded more and needed the extra clearance. But when I built my first motor a few years back the directions said to gap your second ring wider, because it would help gases that built up between the two ring escape, and prevent the first ring from wanting to lift off it's land. What's your take on this Rick????

IntenseBlue · Mar 13, 2006

How do you set ring gap? My shop teacher said they were preset. Also, how do you set the openings? The gaps of my 1st and 2nd were lined up like this:
____

....... ____

and my oil rings looked like that or they were like this:
___
___, with the expanding one in the middle.

Hope that prints the way I typed it. Anyways, he said they should be on opposite sides of each other. Thanks for your help and I hope I didn't hijack the thread.

Modular2v · Mar 13, 2006

some rings do come preset

Rick 91GT · Mar 13, 2006

With a file to fit ring you "file" the rings to the proper gap using a ring filer or hand file.

Gap the second ring larger, it helps get out the trapped gases and promotes better ring seal up the top ring.

IntenseBlue · Mar 13, 2006

Are the openings supposed to be placed on opposite sides of each other?

Rick 91GT · Mar 13, 2006

Follow the instruction, usually the top and 2nd ring are 180 degrees apart.

IntenseBlue · Mar 13, 2006

Alright thanks.

Modular2v · Mar 14, 2006

Rick 91GT said:
With a file to fit ring you "file" the rings to the proper gap using a ring filer or hand file.

Gap the second ring larger, it helps get out the trapped gases and promotes better ring seal up the top ring.

rick just out of curiousity....what happens if you dont file fit them?....i was thinking, whats the worst that could happen?

87'GTstang · Mar 14, 2006

Jason 302 said:
It's interesting how gap recommendations have changed. My old man said years ago they always said to gap your top ring wider because it took more heat than the second and therefore expanded more and needed the extra clearance. But when I built my first motor a few years back the directions said to gap your second ring wider, because it would help gases that built up between the two ring escape, and prevent the first ring from wanting to lift off it's land. What's your take on this Rick????

Well they never changed to "gap the top less" now. The gap hasn't really changed for the top ring, even though it takes the most heat. The only change is they want the 2nd ring a little wider so as to vent the gases and help eliminate ring flutter (so a pressurized pocket of air doesn't build up between the two and have nowhere to go).

Rick 91GT · Mar 14, 2006

Modular2v said:
rick just out of curiousity....what happens if you dont file fit them?....i was thinking, whats the worst that could happen?

If you do not file a "file to fit" ring they will butt together, have no gap and destroy the cylinder walls and pistons. If you buy a pre gapped set you get what you get....maybe not what you want or need.

Rings are filed and matched for the cylinder, then de burred then installed.

Ring Flutter is a huge issue and can cause broken rings, lifted lands and blow by, keeping them stable especially on a power adder motor is very important!

Modular2v · Mar 14, 2006

so on a ring that is file to fit, there will be no gap when put in the cylinder? that is weird

jaredgoodwin · Mar 14, 2006

You file the ring to the gap you need.

Rick 91GT · Mar 14, 2006

Modular2v said:
so on a ring that is file to fit, there will be no gap when put in the cylinder? that is weird

Yes if you just pulled the ring out of the box installed it on the piston and put it in, the ends would butt... YOU FILE THE ENDS TO THE GAP REQUIRED.

Modular2v · Mar 14, 2006

i see...rick i sent you a message

ring gap questions

Modular2v

txstang84

jerryD

bluevenom867

I will have images of molesting stuffed animals in

Modular2v

Rick 91GT

Mustang Master

Jason 302

IntenseBlue

Member

Modular2v

Rick 91GT

Mustang Master

IntenseBlue

Member

Rick 91GT

Mustang Master

IntenseBlue

Member

Modular2v

87'GTstang

New Member

Rick 91GT

Mustang Master

Modular2v

jaredgoodwin

New Member

Rick 91GT

Mustang Master

Modular2v

Similar threads

ring gap questions

I will have images of molesting stuffed animals in

Mustang Master

Member

Mustang Master

Member

Mustang Master

Member

New Member

Mustang Master

New Member

Mustang Master

Similar threads

Privacy & Transparency

Privacy & Transparency