b16a2 10.2:1 2000 Si untuned 40,000 miles w/ Vortech (out of 73,000) I couldn't find what the service limit was in the Helms (or search), the car runs fine, idles well (with a little searching sometimes) but doesn't smoke the tires the way it used to. Put new plugs in a few weeks ago and during compression test the 3rd cyl plug was a little more white than the rest.

Mac gauge (previous gauge read much lower numbers all around, which almost made me shat myself). Throttle plate open, all plugs removed, engine cooled for 45 minutes, fuel injector clips removed:

4 - 200
3 - 170 (+ cap full of oil = 200)
2 - 200
1 - 200

Is it an end-all issue that if a cylinder at 170psi goes up to 200psi with an oil cap worth of oil that it's the rings? We were wondering if possibly oil should have made a more significant difference. Out of hopes that it's due to carbon build up around one of the valves I was going to go ahead with a leak-down this week-end, but I was wondering if I should just give up and being planning a course of action for a rebuild.

For a rebuild, would it be sufficient to swap in new rings, clean off the pistons and re-assemble as long as the sleeve bore on # 3 isn't scratched up? I read in the Helms that if your finger nail can't catch the scratch then boring it out isn't required. I'd like to see if I could postpone the expensive route most seem to take. I only plan on running 10psi w/ Hondata, I just took too long to isntall the Hondata and got what was coming.

 

I'd say iif you were to rebuild right now, you would have no problems just putting new rings on (I would do rod bearings too while your at it). But really you wont know until your rip it apart, I bet your cylinder hone is still perfect though.

 

Hopefully there wont be too much down time since it's my only car until I get a new 350 for the 68 chevy camper special my dad just gave me. I was hoping to put a new motor into the truck before working on my car but it looks like we'll be doing both at the same time

Thanks for the tip!

 

Check the compression when the engine is at operating temp.

 

back in the day on a stock b16 i had a ruff idle.. and low compression on 1 cly.

i added oil, and it held comprssion for a few revolutions, so i did a rebuild. found out 1 valve was bent.

so go ahead and bank on taking the head off and really finding out whats wrong.

oil, or oil + sugar, is only temporary.. somethings wrong.

 

^ That sucks. lol

 

A whole cap? That's a shitload. You're only supposed to use a tablespoon i though?

But yeah, something's wrong. You'll need to tear off the head for starters. Check out the valves. But more than likely you'll have to rebuild.