umadevo

iTrader: (3)

My car started running like crap. I did a compression test and found #3 and #4 were 110 psi compression while #1 and #2 were 160. My waterpump was also spewing antifreeze. I tore it down and am at a loss as to why I had such low compression. My cylinders look fine, the headgasket was intact and undamaged. The piston rings aren't worn. Everything in the bottom end of the motor actually looks pristine. Although I did find something that has stumped me. My #4 Piston has gouges in the top of it. I've taken some pictures to show. Any ideas? The valves on #4 look fine aswell. I'll take some pictures of the head next.





Other than the carbon buildup on the pistons from running mad rich, do you think my timing could be off? Could that be caused from excessive knock? I'm really at a loss. Throw your ideas please. The scratch marks in the center are from scraping off some of the carbon residue with a screwdriver.

teribble

iTrader: (31)

how do your spark plugs look? It almost looks like some rocks were in there. Maybe you lost a piece of a spark plug and it got smashed around then out the exhaust. Its a long shot but something was defiantly in there that should have been.

umadevo

iTrader: (3)

I had just replaced the laser iridiums in a previous attempt to fix what 'hiccup' my car had before. Those looked fine when I took them out. No broken pieces or anything.

umadevo

iTrader: (3)

So after getting the head to the machine shop, I found that I have 2 bent intake valves. One on cylinder 3 and one on 4. It had scored the port itself, so I'm putting in 1mm oversize valves. Also Kelford 272 cams, supertech springs and retainers, and port and polish. Yay.

tsitalon1

iTrader: (3)

How did they bend....Did you ever overrev the motor? maybe on a missed shift?

blk-majik

iTrader: (6)

sounds like something may have passed though the valves and bounced around the combustion chamber. You might want to check the turbo as well for fan damage. your exhaust valves and plugs were ok? Might not have been anything too large. what kind of air filter setup are you running?

then again, the piston damage does look to be all around the valve reliefs, so i wouldn't jump to conclusions yet.

Mad_SB

iTrader: (8)

something has been bouncing around inside there for sure... I second having a look at both sides of the turbo for damage.. whatever got in there either cam before or after the cold side and made it's way out the hotside.... may as well have a look while it's apart.

umadevo

iTrader: (3)

Turbo looks good, hot and cold side. I'm thinking it had to have been like this when I bought it. I bought it for hella cheap and wondered why. Now I realize the "50 year old man" that I bought it from must've known something happened and wanted to get rid of it before he had to do a complete rebuild. It had a hiccup when I bought it and I figured it was just old plugs.

I had the stock airbox setup.

I just ordered a bunch of parts from STM Tuned in New York. They hooked me up with a hella deal on everything I need in the head. I decided to go with Kelford 272 cams and Supertech Valves. Got the whole shebang on the way. Cant wait to get it to run tho.

sfearl1

iTrader: (4)

what was the previous 'hiccup'??

ugakirk

iTrader: (14)

Is this an Evo 8 or a 10?

sfearl1

iTrader: (4)

^^good catch. looks like he drives an 8...

umadevo

iTrader: (3)

yeah I posted in the wrong section >.<

WHTEVO

iTrader: (18)

Say hi to detonation.

Good luck getting it back together.

Aaron

umadevo

iTrader: (3)

What do you mean say Hi to Detonation?










Alright so, got the car down. Everything bottom end looked brand new. Bearings had absolutely no wear and perfect clearance on the crank. Rings looked great. Found the problem tho. At some point (i think when i first bought the car it was like this then progressively got worse) something went into the head, ****ed up a valve, into the cylinder, bounced around causing those impressions on the piston, then out the exhaust valve. My problem was a 'leaking' not blown headgasket and a bent valve failing to close. The head is at the machine shop now getting ported and polished and oversized valves, springs and retainers put in. Didn't want to do a head build - but will get me to where I want to be more reliably. Everything bottom end wise looked great.

The leaking antifreeze was the water pump, which I have a new one already from STM to replace. Just waiting on little stuff, and getting some sex done at the machine shop like new exhaust manifold studs, downpipe bolts w/ springs, and awesomeness to that effect.





sex


Also replacing the wheel bearing.
finally got it out. going to press the new one in as soon as I clean the hub assembly up. Updated parts a bit.








new waterpump installed



Oh yeah.. And new shoes

GUnited

iTrader: (1)

heyyy i like!