I have a b18a block (.25 over)and putting in new pr3 piston(.25 over) and rings (.50 over). Reason I went .50 over with the rings is that the .25 ring was at about .020in over the recommended gap so I went with the .50 over ring so I can just file it down to the proper gap size. But what about the oil ring, do I file the oil ring rail and oil ring or just the oil ring rail. If I was to file down the oil ring the grooves or waves wont line up. Will that be an issue if it doesn't line up?

 

What is your piston to wall gap like if your ring end gaps are that big? Are they OEM rings?

 

Did you have the block bored over .25 or was it like that and your throwing new pistons and rings in. If you just had it bored and honed, you need to make a trip to your machinest and ask him where he left his glasses.

 

I don't know the piston to wall didn't ask I guess since they have over 25+ years experience and through word of mouth heard they were pretty good I figured they knew what they are doing. I'll give them a call on Monday and bring it back to have them measure the bore. As for the rings it was oem .25 over with the pistons from honda but I returned the rings and got the hastings .50 over.

Another thing is that when I put the rings in push it with the piston 3/4 down and 2in down the cylinder there is a .002in difference. Is that how it is or something is really wrong here. Gonna double check this tomorrow.

 

Sorry guys reread my post and as for the rings being 0.020 it is 0.002 over the recommended gap clearance. Thinking about it again .002 is not that big of a difference.

Should I have just installed the .25 over rings from honda since they are only over the recommended gap by .002?

Or was it a good choice to get the .50 over rings and filed it down to the recommended ring gap?

This is my first motor that I am building on my own so I want to get this motor built the right way so that the only thing I have to do to this motor in the future is maintenance work. Thank you for your help.

 

what where the actual gaps for each cyclinder?

 

Piston ring gap from the chilton book

Top ring is .008in - .014in I got .016in to .017in with the .25 over OEM rings on all four cylinder.

Second ring is .016in - .022in I got .024in to .025in with the .25 over OEM rings on all four cylinder.

Oil ring is .008in - .020in I got .023in to .025in with the .25 over OEM rings on all four cylinder.

When I put the .25 PR3 piston in the .25 bore over cylinder it is pretty tight barley any movement of the piston.

As for the .50 over hasting rings I plan file it down so I have it at .011in for the top ring, .019in for the second ring, and .013 for the oil ring.

 

your gaps are still within service limit......
Top Ring: Service Limit: 0.60mm {0.024in)

Second Ring: Service Limit: 0.70mm {0.028in)

 

I don't think the over sized rings will fit well enough. Sounds like trouble

 

thats what she said

 

Where did you get that info from cause I am going base on the info in the chilton repair manual. Damn it could of been finish with this if I knew I did not go past the service limit.

 

Taken from factory acura service manual
Top Ring
New .008-.014
Service limit .024

Second Ring
New .016 -.022
Service Limit .028

Oil Ring
New .008-.020
Service Limit .028

 

Helms.....

 

You will be fine, file the rings to fit like all real engine builders do.

 

Are you sayin to use the .50mm over rings in the .25mm over bore? I always thought you couldn't do that?

 

Depends if you own a ring filer, or a set of small files and a feeler guage set. Some engine builders do, assemblers do not.

 

well thats a given, I thought the ring would become out of round or something

 

Why?

 

Idk, Ive always been lucky enough to use forged pistons with file-to-fit rings. Thanks to DonF I get to learn something new everyday!

 

Since it took a month to get my .50 hasting rings during that time I purchase a ring filer from Summit Racing.

http://store.summitracing.com/partde...5&autoview=sku

But, I am still unsure for the oil ring does the wave's of the ring have to line up when the two ends meet cause won't they overlap each other.
Will this cause any issues in the future or it should be fine?

Thanks for everyone's help I really appreciate it.

 

You should be fine, do not overlap them.