JDM B18C(R)
Upgraded Valvetrain w/ ARP hardware
OEM 4-1 Header and Exhaust
Apexi Power FC
Last dyno was 184whp and 128wtq Dynojet on 91 oct

Started smoking and losing oil some months ago...
https://honda-tech.com/forums/all-motor-naturally-aspirated-44/my-valve-seals-bad-2673919/

Coming home on the highway yesterday morning, was going about 220kph, then the speed started to drop and rpms was falling.
I came down to cruising speed and started hearing a misfire.
The car shut off a few times before I got home (22km journey).
A lot of oil spew out of my valve cover nipple, I pulled the plugs and #4 plug was destroyed.



#4 combustion Chamber



The car has been losing power over the last 2 months though.

Thoughts? Ideas? Questions?

 

well it definitely detonated.

 

Did you have it dyno tuned, and if so, what did the graphs look like from the dyno? What do the spark plugs look like?

That would probably be when the piston ring land failed.

 

what type of upgraded valves are they?

 

I was reading your other thread and saw that ur afr's were 12.7 at high rpm... That's kinda high. I like them around 11.5 to 12.00 max and leaning out would cause detonation but i dont get why it took so long to do that unless the motor was just dealing with the high afr's and finally said **** this.... Also when u rebuilt the motor the rings might now have ever really set right. How did you break the motor in?? On a dyno or street. Was it a hard break in or nice and easy??

 

This is a quote from your "Are my valve seals bad?" thread.

What RPM? What wideband O2 and gauge are you using?


40538350

 

EFjoe91, It was Skunk2 Pro forged flat faced valves, their springs, retainers, and cam gears (@ 0,0)

BOOSTED RHD CRX, I broke in the motor kinda hard, with some non-synthetic oil for the first 1000 kms.

GhostAccord, I got the 12.7 @ 8900 rpm and I was using a AEM wideband I bought new and had it in for 10,000kms total time.

This was the last street tune before I put in the Pro 2 cams.


I never went on the dyno with the Pro 2 cams though, I was having some tuning problems so I pulled them out and put back the stock cams.

I'm guessing, the damage took place while I had them in?

 

Was the engine loosing/burning oil before or after you put in the Pro2s?

If it started before the swap to the Pro3s then I would say adding the pro3s just exaggerated an already ailing situation. I would guess that when you started seeing smoke/loosing oil is when your ring lands failed.

Who tuned it?

 

It consumed a qt of honda 10w30 every 1000 kms, which I think is alot, but I do drive the car hard... everyday.
The consumption accelerated after the cam swap.
I tuned it myself.
The Low cam tune made nice power, it would pull hard in any gear. But the high cam I couldn't figure out, it felt lazy when vtec engaged. My AFR's were in the mid 12s but my plugs were black. I added timing in that area, but never heard knocking, neither did the Power FC indicate knock. The timing in vtec was a bit high, as much as 55 degrees above 8200rpm.

 

No offence but the u tuning it yourself might have had a little to do with it. Its just hard to do a perfect tune yourself. You might have also had a pre existing problem when u rebuilt the motor. The ring lands might have been some what weak and replacing the rings wouldn't have fixed the problem. So they might have just gotten worse till they broke. I'm not expert by far, just giving my opinion. Either way since she blew it needs to be rebuilt anyway.

 

1qt of oil for every 1000 kms is a bit excessive, even when driven hard. I would say the condition was there before the cam swap.

Have the cylinders inspected, get some new pistons, bore it 0.5mm or 1mm, and have someone clean up the combustion chambers for ya!

 

None taken! There aren't many tuners here in Trinidad so I figured I'd try myself.

And you may have a point about weak ring lands. When I bought the car 4 years ago it had a nitrous kit installed. The owner told me he only used it a few times. I had him take it off before I bought it.

When I did a compression test, the resuslts were #1=215 #2=215 #3=215 #4=160. I knew from day one, I had to rebuild the engine. It also consumed oil back then too.

So you think the head could be re-used?

 

Ya i had a nitrous kit on my car as well and i only used it a few times till my motor blew. You could only have to use it once and things will break. Its just so rough on the motor that things will eventually break. But yes the motor and head are reusable it just needs to go to a machine shop and get cleaned up a little bit. Might as well get the seals checked on that #4 cylinder and put 4 new valves in it. Also have the block sent in and if possible have it honed or if need be get it bored, but that means new pistons so it will get rid of your ring land problems.

 

Boosted 11.5 - 12 not low for a Stock NA motor at WOT
just asking

 

yeah, 12.7 a/f with all motor apps is not lean at all, it's a hair rich but no biggie.. looks like detonation? wait for some top dogs to chime in

 

That seems ridiculous! I've never tuned a Honda that needed that much advance. How did you end up at 55 deg. around 8K?
N/A, I'll start at 20 - 25 degrees and add two at a time to find best torque. Trim fuel to find best power, and I'll usually end up somewhere between 25 and 30 deg at WOT.

 

holy timing LOL.

 

Yeah, I screwed myself on that tune!

 

Honestly your quite lucky you got away with the light damage you got.

You should be able to get away with a new set of oversize pistons and cleaning everything else up.

If you switch to a more commonly used ECM management setup you may be able to get a member with a similar setup help you with a map that may only need mildly cleaned up afr's.

 

I must admit the Power FC is great but very tedious and unforgiving (no knock retard function). I bought it cause it was plug 'n play.
A pal of mine was suggesting I junk the Power FC and get Hondata S300.

Now, in #4 cylinder there is a little damage where the piston crown broke off, so I'm not to sure if .25 over will be enough. I'm going to carry it to the machine shop next week to have it looked at and fixed if possible.

I've also decided not to re-use the head but rather get a newer B16A head and have it ported like the ITR head or better.

Before the engine blew I bought oversized piston rings, but I couldn't seem to find OEM JDM ITR pistons in 81.25.
I wouldn't mind upping the compression to maximize the Pro2 cams though.

 

Holy ***** Batman! Cheese n Rice! ???

 

That head is defiantly re-usable, just a little clean up work.

JDM P73 OS

 

^ Sweet! Those pistons will save me a lot of money. I just hope .25 over will be enough to fix the cylinder.

Now, if I can get a B16A head for $120-$150, should I take it and spend $500. on a mild port and valve job or try to fix my head?

I have no idea how much it will cost to fix though, neither do I know what 'fixing' entails.

 

Update: I pulled the pistons...


I sent the block to the machine shop and they told me that 10 thousandths over bore should fix the block. Should I go ahead and purchase the 81.25 mm JDM ITR piston, or buy a larger sized after market forged piston and get the relevant rods?

 

holy cow!