boosted94gsr

I recently rebuild a LS engine for my Eg hatch. I was breaking it in na then was going to add my pieced together turbo kit and have it tuned. Well the engine was smoking very bad (blue smoke under load). It would burn a quart of oil in 150 miles. So I plulled the engine back apart. I had a reputable machine shop do all the machine work for me then I assembled the engine. This engine had perfect compression 187-185-185-189 so I'm really thinking it was the oil control rings. I was using conventional 10-30wt oil.

Build details
B18a1 block
81.5 Nippon piston
OEM spec ptw clearance
Stock rods resized with ARP bolts
Top compression ring gap .018
2nd compression ring gap .021-.022
Oil control rings .045-.050 ( I am thinking this is my oil burning problem)

B18a1 head
B18b1 cams
Crower valve springs
Crower ti retainers
Super-tech valves
New valve seals
When i pulled the head i measured valve guide clearance and it was a little loose so im having new guides and a valve job done while its off.

I just bought a new set of rings NPR for 81.5mm pistons. Six of the oil ring gaps are .018 and two are .024. All the compression rings are good.

This still seems loose to me. Is that gap too big??
Should I buy a set of 82mm rings and just file fit the oil rings??

When all said and done I'm only looking to make around 330whp with a precision 5431e billet wheel turbo.

Thank you any help is appreciated.

boosted94gsr

This is how I clocked the rings. Forgot to add that.

turbohatch96y7

iTrader: (15)

I've never tried to gap the oil rings as they are too thin.

Where did you get your nippon pistons from? And how much?

How much power you pllanning to make on those?

boosted94gsr

I bought them new on eBay for $180 shipped. I am only looking to make around 330whp.

The gaps on the oil rings seem too big to me out of the box. The specs I have say oil ring gaps should be .008-.020 with a service limit of .028 if I remember correctly.

viper_boy403

iTrader: (1)

sounds more like the bore is too big

boosted94gsr

The machine shop had my pistons when they set the ptw clearance. I told them to set it on the looser side of OEM spec no looser then .0016. The piston fit nice and tight in the bore without binding up.

boosted94gsr

Basicly I'm just wondering if my current oil ring gaps (.018-.024) is too big to run? I don't want the engine to burn oil when I get it back together!

Do you think my original oil ring gaps (.045-.050) was why the engine burnt so much oil? I'm sure the loose valve guide clearance may have contributed to the oil burning a little.

Dense147

THIS

wantboost

iTrader: (2)

I've never gapped them and honestly I've never heard of anyone doing it.

the top and bottom oil ring gap isn't that important as it's the middle scrapers job to really control the oil. I would say try it as is because your only other option would be to call/email whoever you got the pistons from and see if they can supply you with an oversize oil ring set that you can try to properly gap but like turbohatch said, they are really too thin to gap without damaging them. either that or source another block with a stock bore and try again.

I've seen a few people who go on the looser side of OEM clearances have issues with the oil control rings... there's a reason OEM bores are a certain size and are almost never towards the looser side.

blackeg

wow my ignorance, i dont think ive ever checked the gap on the middle oil ring, just the thin ones, which you are correct they are super thing and would likely bend if you file them.

i also always thought the thin oil rings gaps just needed to be .015+. personally ive run up to around .035-.040 on those thin oil rings and not had an issue with the engine consuming oil through the rings. (valve guides are a different story)

i have seen issues on oem motors that burn oil because the oil control rings got gummed and sludged up from improper maintenance

met

This is how I set mine done them twice now.
http://www.laskeyracing.com/shop/ringgap.htm
Just to add some of these people posting too have been through may more rebuilds than I have.

boosted94gsr

Thank you guys for the help I really appreciate it! I'm going to just install the rings I have. After comparing my gaps to the ones in the link above I should be just fine.

I just wonder why this engine burnt so much oil the first time around? After a couple hundred miles the pistons were completly gummed up with oily sluggy carbon (the best way i can discribe it lol). All the research I did pointed to the oil rings because my compression was perfect.

boosted94gsr

WTF!!!

Got the car put back together. Drove 20 miles varying rpm and loading the rings pretty good. Came back pulled the plugs to see a ton of fresh oil sitting ontop of every piston!! What the hell am i missing here?

Ring gaps
Top ring .016
Second .020
Oil rings .018-.024 (only 2 are .024 the rest are .018)

I cant believe i have to rip this thing apart again!

J.Berta

Rings isn't your problem if you just ran it and have fresh oil "sitting" on top of the piston...

turbohatch96y7

iTrader: (15)

The 2nd compression ring stops most of the oil..

Maybe you put them on backwards??

boosted94gsr

I am 110% they were installed correctly. Clocked just like the pic above I posted.

boosted94gsr

The head was just completely rebuild. New valve guides, new valve seals, 3 angle valve job. what do you think it is then??

wantboost

iTrader: (2)

A valve seal could have been pinched or ripped during installation or when the valves or valvesprings were installed.

if it was a ring problem then the oil would've burned off during the combustion cycle. if oil is sitting on top of the piston then it's a topend seal issue.

was the oil to one side or area of the piston more than others? if so start there.

met

What do you mean topend seal head gasket maybe?

NotARaCist

iTrader: (1)

Valve stems, spark plug well seals, or head gasket.

boosted94gsr

I pulled the exhaust manifold and took pics. This is after only 20 miles. There is clearly unburned oil in cylinder 2,3,&4 number 1 is the only normal looking one. So you guys think its the valve stem seals then?

met

How could the well seals cause a leak into the cylinder assuming the plugs are sealed. I would believe they would cause the hole to fill up with oil. Leakey valve steams are fairly easy to see if you take the manifolds off.
you posted that as I was typing. yeah valve seals. Just to add in the one pic I think I can make out oil on the back of the valve where it ran down the stem.

boosted94gsr

Just took it for a spin and it is definitely blowing a lot of blue smoke under engine load. It seems like rings and valve seals to me. I'm getting really frustrated with this damn thing! About to set the ****** on fire!!!

turbohatch96y7

iTrader: (15)

Honestly the best thing to is to leave the car parked walk away for a couple days off.

Go get some cocaine and some hookers and clear your head.

I been here before I know how frustrating this is.

boosted94gsr

Lol thanks dude.

I'm gonna wait until Monday and talk to the machine shop that rebuild the head.