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Old 06-06-2002, 01:23 AM   #1
hayscoob
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Default Can you say OUCH!...check it out.

My rebuilt block is back. Here is the pic of the piston that failed. Nasty eh?
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Old 06-06-2002, 01:25 AM   #2
hayscoob
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Here is a pic of the block after the pistons, O-rings and rods etc.
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Old 06-06-2002, 01:41 AM   #3
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Phew! That piston got toasted! But your new block looks immaculate, nice. How much was the rebuid?
Good Luck with it after you get it all back together and on your car.
Paul
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Old 06-06-2002, 02:00 AM   #4
hayscoob
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Paul,

The rebuild cost about 2800 bucks. It included new custom forged 8.5:1 pistons, chromoly forged shot peened rods, knife edged balanced crank and O-rings. Of course it also came with a perfomance bearing kit for the rods and stronger wrist pins. All I need is some top end work and I will be able to run gobbs of boost. That is when I get the tranny rebuilt later on. I plan on running about 12-15 lbs of boost if the valves can handle it. I may have to shoot for lower boost if they can't handle it.

Paul...
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Old 06-06-2002, 02:00 AM   #5
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hmmm...detonation anyone?
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Old 06-06-2002, 02:43 AM   #6
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Hey Paul,

The block looks good. Can't wait til you get that installed and take it out for a test burn. Maybe we can find that guy with the del sol and mess around with him.lol:

Kenny
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Old 06-06-2002, 08:58 AM   #7
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Damnit! I think you blew off a bigger piece of piston then I did last time. I guess I'm just going to have to try harder this time.

Nice looking block, BTW.
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Old 06-06-2002, 09:00 AM   #8
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upgrading the valve springs and retainers at least?

Jon
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Old 06-06-2002, 10:02 AM   #9
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$2800 for all that stuff? I want some names Hayscoob!

The block looks incredible. Did you have to have the block bored or did you use standard bore pistons?


Graham
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Old 06-06-2002, 12:13 PM   #10
Eric SS
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That looks EXACTLY like my piston did.

Eric
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Old 06-06-2002, 12:17 PM   #11
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So who assembled the new block ? I'm assumin these are JE pistons but who makes the rods ? pauter ?

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Old 06-06-2002, 01:51 PM   #12
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god damn...2800 for that lil bit of work?? i'm in the wrong field *shrug*
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Old 06-06-2002, 02:59 PM   #13
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I can't believe how small the skirts are on our pistons. I don't suppose the forged ones look any better do they?

~Garrett
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Old 06-06-2002, 04:23 PM   #14
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Garrett - Nope. There is only like 3-4mm of clearance below the piston at BDC between the skirt and the bottom of the cylinder bore.

You wanna stroke a 2.5L motor? It better be destroking.
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Old 06-06-2002, 07:19 PM   #15
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hayscoob, so did you determine that the cause of the problem was a lean condition in cylinder 3? Would a parallel fuel modification have helped?
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Old 06-06-2002, 10:41 PM   #16
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Graham: The block was bored out to 30 over. The cylider wall of #4 needed it. These pistons were special ordered to fit my application. Shelf pistons wouldn't have worked. I think I already told you who did the work. If not PM me.

8complex: After looking at your pic of your piston, I wondered what mine was gonna look like. I almost craped my pants when I saw it. The piece of piston that broke off did considerable damage to the piston as it tossed around in the combustion chamber.

zaidallas: The pistons are indeed JE. The rods are Pauter.

RallyNavvie: The skirts are small but they have what appears to be a Teflon coating on them. I can't believe how thin the pistons are above the first ring landing. I can see why it would be weak at the valve releif area. The material is very thin there. Seems to be a weak point and when they go they go there i assume.

Brood: I have yet to determine what caused the "problem". I think I spiked some how. There also may have been a time prior to the major failure that the ring landing simply cracked and eventually broke. Ironically, the #3 cylinder was not the one that broke. It was #4. To make it even more interesting, the #4 cylinder is the one that gets fuel first with the stock fuel delivery. I think the Parallel fuel rail mod may have prevented this, then again maybe not. If I spiked on boost, there may have been now way to combat the problem. Another theory I have is boost creep. Perhaps with the high compression motor and crappy 91 octane gas, the exhaust velocity at the wastegate may have overwhelmed the wastegate. Who knows. I pray it doesn't happen again. I am putting faith in my new motor and TEC III to handle the job.

homegrownxt: When it's done you will know it. I have a 1000 mile break in with low low boost. When done I will creep the boost up till I hit 300+ hp// should be about 12 lbs of boost. I think I will be around 330 lbs of torque too, I hope. When I get the TECIII tuned by Shiv, he will dyno tune it when his Dyno is up and running. Till then I can only shoot in the dark about the true fugures on HP and Torque. Wish me luck buddy....

omahasubaru: The bank account is drained from this project so far, not to mention that my mother has been suffering from Stage IV Metastic Breast Cancer. I have been funding some of her issues with her health and her health is my highest priority right now. When I begin to recover from all of this financialy, I plan on having the heads done up. But I will get the transmission hopped up first. I will just have to learn to keep the boost low till I am ready. 300+ HP is enough to shoot for, for now. I t will be comforting to know I can cram more boost into my motor and be way safer doing it now. I am glad it is nearly done. This has beena nightmare to deal with. Getting the parts and waiting for them is a big huge PAIN IN THE ASS! No body has pistons in stock for what happened to my block. I had to get them made to fit after I had the cyliders honed. I think I have a 2.6 liter moter now. Maybe more???

Paul...

Last edited by hayscoob; 06-06-2002 at 10:51 PM.
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Old 06-06-2002, 11:53 PM   #17
zaidallas
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hayscoob : check your pm

zaidoun
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Old 06-07-2002, 03:14 AM   #18
HndaTch627
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why would you have shiv tune a tec 3?? it's got the wintec software to help you learn how to tune it yourself *shrug*
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Old 06-07-2002, 04:06 AM   #19
hayscoob
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He will have his 4 wheel dyno up and running soon and after one blown engine, I don't want to make any more mistakes.

Paul...
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Old 06-08-2002, 01:38 AM   #20
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It's always #4, and lit ooks just like my #4 piston did.

That's a shame about your Mom. I'll keep her in my prayers...
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Old 06-08-2002, 01:47 AM   #21
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Why is it always #4, it shouldn't be a lean fuel condition right?
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Old 06-08-2002, 01:16 PM   #22
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Personally I believe that #4 gets the lowest fuel pressure in the stock lines. Previously it was #3 thought to do that, but I think that is quite wrong.

Take for instance jellybeans rolling down a channel. Since they're already moving at a regulated speed (regulated at the bottom), if you pull one out near the regulator, the rest above it move faster down to compensate and fill the gap. Take three along the line, see how fast the top section moves at that point.

Now I believe it's Bernoulli's principle that states that velocity is inversly proportional to pressure. Meaning, the faster something flows, the less pressure that is behind it.

So since the #4 injector has 3 injectors pulling fuel out between it and the regulator, it naturally has the highest velocity of fuel going by it, thus the lowest pressure.
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Old 06-08-2002, 11:39 PM   #23
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Wow 8, that's an interesting theory. It make total sense. Kind of like an old fashioned perfume bottle with the bulb that you have to squeeze. That would translate into lower fuel pressure at the first junction based on how much fuel and the velocity of the fuel traveling past the first hole. This would be easy to duplicate with clear tubes to see just how bad the effect is. I would like to see it in action. Good thinking dude!

Paul...
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Old 06-08-2002, 11:41 PM   #24
hayscoob
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Larry, thanks for your kind words about my mother. My nerves are shot these days. On a good note, I just asked my girl to marry me and she said yes. So, I am officially semi hitched.

Paul...
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Old 06-09-2002, 01:35 AM   #25
Graham
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Congrats Man!!


8, seeing that our cars obviously have a some sort of detriment in the fuel line system, I devised somewhat of my own Fuel Line Mod. This is not parallel, all I did was simply add a fuel line into the mix. I mentioned this a few months back, but no one seemed to care. Since then, I have documented the entire Fuel Line Mod, and it is posted on the main page over on RS25.com.

Here's the link:

http://www.rs25.com/_How%20To/Fuel%20Rail%20Mod.cfm


Just on a side not, my J&S Sensor is placed DIRECTLY above cylinder #4, so it hears everything that goes on inside, plus a little more. On a hot day, it might pull 4 degrees, and at night it harldy pulls any timing (this makes me happy). I am running 4 psi with around 66 psi fuel press. on boost.

Graham
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