BEST OEM Piston rings

[goldeninja20]

Ok guys. I have been running NPR piston rings for about 8000 miles (on a fresh rebuild) did a slight pull today and then the car ran awful. Compression check results in 55 psi in first cylinder and crazy amounts of blow by. I dont really see why it would be the piston. I am pretty confident that i cracked a ring. I am running 22 psi on a small 16g. The real question is what is the best piston ring for a stock piston?

 

[Dsmkauai]

The best rings are oem ones bro!! You can order them from mitsubishiparts.com for $159 a set! I wouldn't use anything else (unless of course you go to a aftermarket piston) if trying to push the car over stock boost. Sealed power and tru seal are also great rings I've had good results with! Question for you who built the motor? And was the cylinders checked for out of round or to see if they are even in spec for stock rings? http://www.mitsubishiparts.com/oe_parts_catalog.html?Year=&make=&catalogid=1

 

[92AWDHX40]

RTM Racing :: MITSUBISHI :: DSM: 2g (95-99) :: Engine :: Block Components :: Pistons & Rings :: NPR Pistons Rings for OEM & OE-Style Pistons: 2g DSM

right here try rtm factor replacement parts.

 

[goldeninja20]

RTM Racing :: MITSUBISHI :: DSM: 2g (95-99) :: Engine :: Block Components :: Pistons & Rings :: NPR Pistons Rings for OEM & OE-Style Pistons: 2g DSM

right here try rtm factor replacement parts.

Those are the same rings i just ran. Like i said, I havent had a chance to tear it apart yet, But I either cracked a ring land or a ring.

 

[92AWDHX40]

Well the best ones there aren't too many places who make better oems ones. I would consider forged if you don't want to chance oem oones again.

 

[goldeninja20]

Well the best ones there aren't too many places who make better oems ones. I would consider forged if you don't want to chance oem oones again.

Realistically I did not think i was risking them since i am under 300 hp.

 

[Dsmkauai]

Use oem Mitsu rings!! Not oem replacement rings unless you want problems! I would only use oem replacement rings on a motor that is light load or non turbo! Just wouldn't trust them to hold 20psi or more!

 

[92AWDHX40]

Well something else happened you never know no matter what the hp,, something happened gonna have to tear it down and figure out if you want to run them again, but not sure if there are any better ones, even aftermarket stuff can be installed wrong or have issues if something is done wrong.

 

[LandSpeed-DSM]

I think we are getting ahead of ourselves. Stock is NPR. Have you determined what happened yet?

Ive been running NPR pistons and rings in this short block since 2008, most of which was around the 600whp level, with no issues. You could just as well be doing this again if the issues that caused this remains.

 

[Dsmkauai]

^^ for some reason I was thinking of dnj (Rockauto brand) not npr! Sorry Chris! I don't recall the new set of rings I got saying npr on them only Mitsu. I got mine thru Mitsu and they have Japanese all over the packaging! I'll have to check again Monday when I get to my shop.

 

[92AWDHX40]

I agree with land speed I run the same ones for years and no problems ever, 20 years strong.

 

[goldeninja20]

I think we are getting ahead of ourselves. Stock is NPR. Have you determined what happened yet?

Ive been running NPR pistons and rings in this short block since 2008, most of which was around the 600whp level, with no issues. You could just as well be doing this again if the issues that caused this remains.

The tune has been perfect for me. 11 afr in boost. Timing stock for now. I was a little unsure of the npr being OEM. I may have well broken a ring landing in not too sure. I just purchased another set of npr because they seem to be trustworthy. The mistake could have laid elsewhere.

 

[92AWDHX40]

Yes sounds like another problem not the ring itself, the brand is good, designed to replace the oem stuff. I run them In my cars and plan to until I blow a engine up.

 

[goldeninja20]

Just want to clarify for everyone! Got the motor torn apart. It was the ring lands. The rings held up great! I will be using them again.

 

[BogusSVO]

What were the ring gaps set to at the last build?

Ring lands do not break/crack for no reason.

 

[goldeninja20]

What were the ring gaps set to at the last build?

Ring lands do not break/crack for no reason.

I will be honest. I dropped in the npr rings without checking gap, I assumed and knew they were oem replacements and I figured they were gapped correctly. I was not running lean (according to my wideband). Really the only thing i can think of is that I got bad gas. Im only running 23 psi on a small 16g. I would love others opinions though. Here is a picture of my head. Cylinder 1 (all the way to the right) was the one with BAD broken ring lands, While cylinder 2 only have one slight crack (compression was still 135). I would love some help so this doesn't happen again.

 

[BogusSVO]

All ring gaps need to be checked.

You are going over factory boost levels, so you are generating more heat, and that causes more ring expansion.

 

[LandSpeed-DSM]

I will be honest. I dropped in the npr rings without checking gap

Case closed, folks.

 

[goldeninja20]

All ring gaps need to be checked.

You are going over factory boost levels, so you are generating more heat, and that causes more ring expansion.

So you think this may have resulted from the gap being too small?
I will be sure to check it this time.

 

[BogusSVO]

Yes, I would be fairly certain of it.

 

[goldeninja20]

Yes, I would be fairly certain of it.

I know you have responded to multiple "what should my gap be" questions. Heres another one for you. . The most ill ever push my motor is 25 psi with a 20g (if that). What would you consider a good gap for 1rst and 2nd rings (6 bolt)?