This is on my autox car:

B18C5 from 2000 itr with about 75k hard miles NA and 5k miles boosted.
jrsc with LHT a2w cooler
(gsr/itr cam combo)
injectors and fuel pump (RC and walbro respectively)
full ATS transmission
Running on E85

(I currently have no black box / breather, and no PVC valve - vented the upper port from the block to atmosphere.)
(The valve cover is vented to a catch can.)


*only relevant mods posted

Only recently I checked my oil on a cold day and was shocked to find the underside of the oil cap had a milky residue on it.
I smelled it and could only detect a faint E85 scent.

Should I be worried?

I've also noticed some excessive oil consumption lately - but have no leaks that I know of.

No oil in coolant, and no coolant in oil.

The motor runs very well though!

 

I'm in no way an expert, but is this a possible sign of piston rings going bad? B/c of the possible gas in the oil.

 

This is one possibility. Also E85 coupled with boost tends to contaminate oil quicker because you need approximately 30% more E85 than regular gasoline. Most people on E85 change their oil more frequently. Try doing an oil change and do an oil analysis maybe every 1,000 miles. If your oil gets contaminated early on then it may be time to freshen up the block.

Also noticed you deleted the PCV valve and are only running a catch can up top. Might want to install one at the block also.

 

Thanks guys, you're both right of course.

Oddly enough, I only found the milky residue once and it hasn't showed up again.

I don't have room for the oe black breather box bc of the supercharger, so I'll need to maybe modify the breather box to be about 1/2 size and reinstall, or do a check valve + drainback setup like in this thread:

​​​​​​​https://honda-tech.com/forums/forced...sense-3270656/

I'll change the oil and do a compression and leakdown test as well.

 

milky residue on the bottom side of the oil cap could be completely normal, and a result of the engine running for short periods of time (short trips to groc stores, idling for 10 min and shutting off). Moisture will buildup in the engine and since it really doesnt have anywhere to go it rises to the highest spot (the oil cap) and after the engine cools turns back into a solid form. If this is an excessive amount than it could be abnormal and need further inspection but if its just the amount that would fit on the bottom of the oil cap, i wouldnt be concerned at all.

 

Not an issue.

 

+1...BAM...found that hammer and drove that nail in with one blow...well stated!