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Old 04-07-2002, 07:56 PM   #1
hayscoob
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Exclamation Ouch!!!

Well, I was on my way south to San Francisco when....In Petaluma, I was gonna get off the highway and gas up. So I stepped on it and was passing a car to make the next exit and something went terribly wrong. Everything was working great. No strange sounds, no pinging, just a spooling turbo. Then the motor stopped it it's tracks. OH CRAP! So I put her into neutral and coasted around the intersection and pulled into a parking lot. No smell, no leaks, nothing. I had to have a flatbed truck pick up my car and transport it to my mechanics house to have him look at it. Once there, I had him pull the plugs. Cylinder 1 plug,ok...cylinder 2 plug, ok...cylinder 3 plug, ok... Then last but not least, cylinder #4. The spark plug looked like someone smashed it with a hammer. I will try to get a pic of it later on. We scratch our heads and wondered what happened. So, he gave me a ride home and went back and started to work on the car. He discovered no strange fluids in the cylinder, No coolant in the oil, weird etc. He determined that the piston and rod are still connected and it moves. However when it comes to the top of the cylinder it stops. He seems to think it may be a valve stuck in there. This problem will not alow him to check compression. Any thoughts??? Has this happened to anyone else? Damn, just another wad of cash out of the ol' pocket.

Paul...
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Old 04-07-2002, 08:12 PM   #2
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Geese, I'm stumped. Something went very wrong, quite obviously.
Spark plug smashed with a hammer......

Hope you get it figured out quick man.

Graham
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Old 04-07-2002, 08:55 PM   #3
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The head has to come off. Sorry to hear. My old bike shop saved every lunched piston they ever , well, lunched and I can tell you it can be part of the bore, the valve, part of the piston, even a rock or a screw. adamsrss'ses was a screw!
Once again sorry.
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Old 04-07-2002, 08:55 PM   #4
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Pull the head... that is the only way to tell unless you get a borescope and take a look (though they're damn expensive). I suppose it's possible that you hit a valve (on float) and bent it to the point where it blocked the cylinder from getting to TDC, but it'd have to be REALLY stuck to stop the motor dead in it's tracks like that.
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Old 04-07-2002, 08:56 PM   #5
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8Complex man you fast!
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Old 04-07-2002, 10:12 PM   #6
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Ouch Paul,
Hope you get it figured out and I hope my J&S will prevent this from happening to me......
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Old 04-07-2002, 10:42 PM   #7
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Scott,

I don't think this had anything to do with detination. I hope...

It may be a valve problem. I pray that the head isn't too badly damaged. I guess I will have to wait and see.

Paul...
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Old 04-07-2002, 10:51 PM   #8
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ummm if it stopped the motor i guarntee you lost a rod...even if you floated valves and destroyed everything it wouldn't have stopped the motor, just turned it into garbage....did you do the parallel fuel rail mod?? how much boost were you running?? need some specifics...i'd be willing to bet your connecting rod bearing load got too high and the bearing was beginning to squish and spin.

Just my $.02

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Old 04-07-2002, 10:51 PM   #9
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I was driving my 63 VW Baja from Colorado to Texas. I was on a two lane road and went for a huge 8-9 car pass. I dropped WAY back and built up speed for it and timed it just right. As soon as I got back in my lane the engine started running like crap. I pulled over, and as all those people passed I checked all the plugs. One plug was smashed flat. I bent it back into shape and took off. Engine ran like nothing happened.

Sorry, but you luck will not be so good. You had a catostrophic failure in your engine. Engines don't just stop cold unless it is really bad. Probably a piston explosion. The only way a plug would smash is if the piston hit it or if a valve got bent around in there and hit it, or if piston parts whacked it. You probably had a piston meltdown and destruct which flung parts around in there and will not let your #4 piston hit TDC. Good luck with the rebuild. Were you running management?

Bummer.

Jon
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Old 04-08-2002, 01:49 AM   #10
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man sorry to hear that....i hope you didn't blow your engine....it always seems to be the #4 piston or some relation to it....what did you do for the pinging at 5000rpm...what kindda gas were you running...this makes me kindda nervous because i have the same exact kit and same year scooby.....good luck

hugh
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Old 04-08-2002, 02:21 AM   #11
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Paul,
Damn! First your leaking problem then this? Definitely let me know, so I can tell my shop about it when they turbo mine. Hope your problem is not serious man...

-Benson (Another MY98 Owner)
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Old 04-08-2002, 02:29 AM   #12
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It's always the #4 piston

I think you have a piece of piston hanging up the movement in there, and preventing the piston from hitting TDC - not a valve.

Besides, a valve isn't going to bend/smash the spark plug.

I personally lost a chunk of piston without hearing any detonation. I believe the 2000-2002 piston has an area of weakness between the edge of the piston and the valve relief cut into the piston.

Larry
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Old 04-08-2002, 02:31 AM   #13
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Quote:
Originally posted by ImprezaRS dot com

I personally lost a chunk of piston without hearing any detonation. I believe the 2000-2002 piston has an area of weakness between the edge of the piston and the valve relief cut into the piston.

Larry
that cause they are cast and not meant to have any kind of detonation...they just form a hot spot and it's all over from there.

jeremy
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Old 04-08-2002, 04:01 AM   #14
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That's interesting, and mostly true, but Shiv & I are both making over 375hp on CAST my99 pistons.

I was running 12-13 psi today at 6,000 feet on 93 octane with only 5 degrees timing retard, and do so often. Eventually I'll break again I suppose, but the MY00 pistons woulda been long gone by now, again...
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Old 04-08-2002, 04:07 AM   #15
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Quote:
Originally posted by ImprezaRS dot com
That's interesting, and mostly true, but Shiv & I are both making over 375hp on CAST my99 pistons.

I was running 12-13 psi today at 6,000 feet on 93 octane with only 5 degrees timing retard, and do so often. Eventually I'll break again I suppose, but the MY00 pistons woulda been long gone by now, again...
are those phase 2 model year 99 pistons?? or phase 1?? and try making that boost down here...it's a WHOLE different world.

jeremy
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Old 04-08-2002, 06:42 AM   #16
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hndatch, please note that its HARDER to make a certain boost level at altitude. You must run a higher pressure ratio on your turbo, and have less dense air going over the intercooler to cool it back down.
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Old 04-08-2002, 08:37 AM   #17
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Unhappy Do I need to worry!!!

Hi, I have a 2002 RS-T. I,m running only 5 psi of boost. Do I need to worry about piston #4?

Elliot
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Old 04-08-2002, 12:36 PM   #18
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Quote:
Are those phase 2 model year 99 pistons?? or phase 1?? and try making that boost down here...it's a WHOLE different world.
They are phase II MY99 pistons (the whole phase II 99 shortblock, o-ringed with phase I thicker head gasket and MY00 heads) and about 9.4:1 CR (although someone did some calcs and came up with 9.0:1 the other day)

Couple of tidbits, Shiv is making 400hp at the crank with 12 psi of boost if I recall correctly (296 @ wheels), on 96 octane gas, so the 375hp I mentioned is a guess of what he makes at 10 psi at sea-level. I have to run more boost up here to make the same power, and 12-13 psi up here is like 10 psi at sea-level in terms of "effective compression ratio".

Although intercooler efficiency suffers at altitude, my dual TB fuel injectors seem to cool down the intake charge very well and improve the efficiency. As the fuel passes the MAP sensor/IAT sensor I can see the intake air temps drop to only 20% warmer than the normal air temp outside while at 10 psi. This decreases my tendency to detonate in addition to the benefits of the lower air pressure up here.

I am also using a more efficient turbo than originally used, swapping the small IHI legacy turbo for a larger VF22 like Imprezer. While this turbo will generate 18 psi on his 2.0 WRX, up here with my 2.5 downpipe and 2 cats (3" catback) I can't get more than 12-13 psi on a warm day when the boost controller is turned up all the way, or 13-15 psi on a cold day (I get less boost in 1st and 2nd, but full boost in 3rd - 5th).

Yesterday I had the boost controller maxed out and before and during our drive into the mountains I wasn't seeing more than 13 psi between 6,000 - 9,000 feet. But that evening when the air temp dropped 30 degrees and the air was more dense I could get 15 psi out of it. I was running 94 octane and it ran like a raped ape.

There is no way I could do this on the 2000 pistons because they would break at the slightest detonation, even so mild as to be inaudible. I'd worry about anything over 5 psi on those pistons without a programable ECU and $500 to get it tuned right. That's when I would be calling Shiv myself.

Larry
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Old 04-08-2002, 01:25 PM   #19
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Quote:
Originally posted by XT6Wagon
hndatch, please note that its HARDER to make a certain boost level at altitude. You must run a higher pressure ratio on your turbo, and have less dense air going over the intercooler to cool it back down.
i know that... i lived at 6k feet for a while...it's hell on cars. what i was sayign is try making 13 psi on pump gas down here, it creates a ton more power. anyhow...back on topic...honestly unless you have a parallel fuel rail system everyone needs to worry about cylinder #4

Jeremy
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Old 04-08-2002, 02:18 PM   #20
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Well, if it turns out that the pistion is shot and not usable, then I would like to rebuild the block with low compression pistons and better rods. Any ideas? Engine management is around the corner.

On another note, I would think Tom @ Ludespeed would and should include some sort of detonation/timming controller for any of the kits he sells. At least for the MY 00-02 RS. Seems that there is a higher failure rate in the 00-02 SOHC engine. This is a minor set back for me at the moment. I never went into this project assuming there wouldn't be any problems. I just didn't expect it so soon. I have been plagued with exhaust leaks from a poorly desigend and constructed up pipe and a failing stock clutch. I have realy never had a chance to experience my turbo car to the fullest extent. I'll be back on the road soon...I hope...Any information about pisons and rods and what compression ratio to shoot for would be nice...Also, where to buy them...Thanks...

Paul...
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Old 04-08-2002, 06:04 PM   #21
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wow how much does something like that cost?? i am putting my kit in next week and have a 2001....any suggestions of what not to do?? i will be running 4.4lbs boost.....thanx and good luck

hugh
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Old 04-08-2002, 06:23 PM   #22
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Quote:
Originally posted by HubbieScooby
....any suggestions of what not to do??
Don't blow it up.

Seriously though... don't get anxious to feel the speed, this is the cause of many post-install dead motors. If there is a problem with the running condition of the car (pinging, other wierd feelings), do not continue.
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Old 04-08-2002, 06:57 PM   #23
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Quote:
Originally posted by 8Complex


Don't blow it up.

Seriously though... don't get anxious to feel the speed, this is the cause of many post-install dead motors. If there is a problem with the running condition of the car (pinging, other wierd feelings), do not continue.
i do recall that hayscoob had pinging at 5000rpms....i'm hopeing to eliminate this by running 92++ octane....i don't have a J&S yet but i was considering the Apex ITC....could that small pinging at 5000k be the cause? Tom has turboed many RS's and im sure he would be aware of a problem....this was weird because my friend had a Minnam stage 2 and was driving his car really hard (autocross style) eventually he did blow his motor but that was because he was messing with the boost....he blew it at like 7lbs with stock internals and no electronics.....my question is how did he last so long with all the abuse???oh his is a 2001 RS by the way....i was hopeing that something as small as 4.4lbs shouldn't be a problem...but now im geting kind of nervous.....hayscoob have you contatcted Tom????

hugh
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Old 04-08-2002, 07:00 PM   #24
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i blew my #4 piston running 4 psi so there is no garuntee...do yourself a favor and get a j&s its a lot cheaper than buying new pistons
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Old 04-08-2002, 09:35 PM   #25
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Well when you get down to the brass tax, the J&S is just a bandaid. If I indeed smashed up a piston, I will rebuild it with low compression pistons. Plus, I will end up installing some sort of a PEM system soon too. I'm finished screwing around. I need my car and I need it to be reliable. It's gonna hurt the ol' pocket book but it's gonna be worth it in the end...

So far, I have not had the head off the drivers side bank yet. I will let everyone know what's up when I do. Stay tuned for the latest news on my car...

Hubbiescooby,

Contacting Tom will produce nothing. He has nothing to offer me at this point to make my car right. It's my own fault for not getting some sort of timing control. I will say for the record "Don't trust your #3 or #4 cylinder at any boost wihtout some sort of timing controll". I am running just 4.4 lbs spring in my Tial wastegate and a HUGE top mount Spearco Intercooler. So, there you have it. I must have spiked some how and she broke. If it spiked, then that will be something you can't controll and will most likely damage the motor. In my opinion, low compression forged pistons are stronger and would better resist against this detonation problem. I would rather run lower compression in my motor for the time being till I have the dough to purchase a Tech II or something. We will see.

To every one else who is reading this thread... Thanks for the support, I need it right now...

Paul...
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