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oldskoolracer
03-29-2006, 10:18 AM
ok, most people know here that one of the most common things to fail on a honda engine with boost is the ring lands, right? i have had a couple of engines do it to me until now, and it was one of the most abused engines of the bunch. This is the engine we ran all last year threwout all the of the track and the constant 2step, just flat out trying to hurt it.
Well the engine lost compression onth #4 cylinder late last year and the other pistons followed shortly after they were like this

#4 52psi #3 47psi #2 87psi #1 105psi

also note that i drove it around like this for a couple of weeks and then parked it a few months ago and then drove it to the shop last week.

We start to pull it apart and it just stinks of burnt oil, the head studs are really tight on the outside bolts and no so bad in the middle ones, we get the head off and start looking for scaring on the cylinders, we are rotateing
the engine and it is not sticking, no problems pushing them down and there is apsolutely no damage to the cylinders for where we could see, odd to a point.

At this point we are interested now in pulling the pistons so wer start that process. We start with the #3 and everything looks fine, meaning there is nothing wrong with the piston even the rings don't seem that bad.
we pull out the other three and the same thing there is no issues with the pistons they are intact, not even any scrapes on the skirts.
The whole thing is just surprising to be honest, servion set it up to be a conservative tune, just to be safe since the engine was kinda low compression to begin with. I'm gonna just hone it rering it and try the sme one out again, why the hell not.

all that hell we put it threw and it looks like a basic old engine rebuild.
i bet if we would have had the guys at honda take a look they wouldn't have even know it was boosted, i've got to get some pics up but it's still hard to see the cylinders unless your looking at it in person.

sorry just a rant, i just wanted to thank servion for tuning the car, if it could hold together like that with me driving it, he had that thing tuned great and safe. i was figuring machine shop time after what we were doing to it.

HONDA GHANDI
03-29-2006, 12:33 PM
The compression had to be going somewhere. Did you find any failure?

Skaterkid
03-29-2006, 12:39 PM
Could it be that the studs in the middle had yielded slightly leaking pressure? It would act like a blown hg I'd imagine.

Weston-work
03-29-2006, 12:39 PM
Yeah, I'd think there would be some visible damage for those kind of numbers. When I had a drop in compression like that in my Prelude, I found chunks of the exhaust valves missing on the low cylinders. Did you check to see if the valves are bent? An easy and free way to check is to take the head off and pour water into the ports and see if it maintains it's level or if water starts coming out in the combustion chamber.

oldskoolracer
03-29-2006, 12:54 PM
i think it had something to do with the head i haven't really gone threw and checked the head yet i plan to tonight

i thought about pushing the head up also i also haven't straight edged the head yet either so that's tonights project,lol

HONDA GHANDI
03-29-2006, 01:46 PM
Exh valves would be my guess too. Time to get an EGT gauge if thats the case.

oldskoolracer
03-29-2006, 03:03 PM
Exh valves would be my guess too. Time to get an EGT gauge if thats the case.


I did pick up an EGT this year so i hope i'll be able to see anything early

boostedEG
03-29-2006, 06:57 PM
what are average readings for EGT? 1300?

oldskoolracer
03-29-2006, 08:48 PM
i haven't installed it yet

myshtern
03-29-2006, 10:44 PM
what are average readings for EGT? 1300?
It depends on location

oldskoolracer
03-30-2006, 08:58 AM
i've been told to put it in the #3 cylinder about an 1" from the head but other people have them in the DP i'm scared to drill a hole in the nice manifold any suggestions????

servion
03-30-2006, 10:33 AM
i've been told to put it in the #3 cylinder about an 1" from the head but other people have them in the DP i'm scared to drill a hole in the nice manifold any suggestions????

That's where you put it :) If you think about it, if its in the downpipe you are not just measuring the temp of the exhaust gases right after combustion... you're also measuring the temp change throughout the manifold, turbo, etc. so, any heat exchange that happens from the manifold/turbo/etc. will also be measured, which begins to defeat the purpose

rmcdaniels
03-31-2006, 10:20 PM
i've been told to put it in the #3 cylinder about an 1" from the head but other people have them in the DP i'm scared to drill a hole in the nice manifold any suggestions????

I drilled a hole in my Lovefab ramhorn manifold in #3 1" from the head and had an EGT bung welded on to it, never had any problems with it.

oldskoolracer
04-02-2006, 01:27 PM
we drilled the hole in the ramhorn manifold and tried to tap it and it just destroyed the tap, it didn't even make a small thread dent in it

servion
04-02-2006, 04:14 PM
Better tap maybe? :P

boostedEG
04-02-2006, 08:24 PM
is it thick enough to simply tap?
i'd weld a bung on it.

oldskoolracer
04-03-2006, 06:59 AM
i'm gonna try a better tap if that doesn't work then it will be time to weld it