Im building my B18C1 for turbo and im trying to get all my affairs in order before i start building. Im trying to figure out what kind of piston ring end gap i should be running for boost.

Specs: B18C1 81.5mm= 3.209" bore

Top Ring: (.0050)(3.209) = .016
Second Ring: (.0055)(3.209) = .017
Oil Rings= Min .015

I'll be using Low Compression CP Pistons with CP Piston Rings
These numbers i got online from the JE piston rings information. When i tried to use the paper provided with my pistons, my endgap numbers came out kinda weird.


I was hoping i could have a couple of experienced people on here help me out to make sure all my numbers are correct. Please thanks.

 

bore x .006 = .019 [1st]

.019 + .004 = .023 [2nd]

That's what you need to use.

 

damn i was way off. thanks man.

 

should the oil rings remain at .015? Just checking

 

I can't remember what I did with the oil rings. I know I followed the JE/SRP recommendations on my build. IIRC I had 0.016 on the first, 0.022 on the second. I want to say the oil rings were close to the first end gap, but it's been over three years since I rebuilt my engine and it was late at night.

The end gap is also determined by your HP goals too. What is your goal?

 

Covered here -> http://forums.evans-tuning.com/viewt...r+engine+build

 

I too dont remember the oil ring gap on my build. But I think I used the same gap as the second ring.

 

I honestly never do anything with the oil expander or the oil control rings. I just install em. I think my first couple builds I checked their gaps buts its never been too tight.

Jeff Evans did one hell of a job writing that article, along with all his others. I highly recommend it.

Good luck!
dk

 

I do normally use JE's methods of clocking the rings however. I've used it ever since my first build.

I also recommend a tapered bore ring compressor, they are so nice. They keep the rings from spinning making it easier to clock them and you can push the piston down in the bore with your pinky never taking a chance on bending a oil control ring.

 

Tapered bore compressor, i have to look into that. I have used a wrinkle band ring compressor before and that worked pretty good for me. If i may ask, how do you use a tapered bore compressor?

 

You just slide the piston down in it, just like you would the cylinder.

Its like a tapered mini cylinder.

Mine are made by wiseco.

 

ok i did my research on the tapered compressors and they look pretty good. my question is, im going to a 81.5mm piston, should i go with a 81.5mm compressor? sounds kinda dumb of me, but i just wanted to make sure if i didnt have to use a 81.75mm or something. thanks