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I think i blew my engine.

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Old 11-22-2008, 09:18 AM
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Default I think i blew my engine.

Hello,
Yesterday I did something really stupid. I raised my boost up to 17 psi and at 4th gear ,WOT and 6k rpms my car felt that it lost some power.
After I pulled over I heard a weird sound like knock knock knock continuesly but no smoke from the tail. The sound is coming from the upper place of the engine.
I found some oil in the oil catch can but not much.

After a quick thought I drove the car towards a friendly garage and the engineer ensured me that something is broken inside the engine, just hearing this awful sound. When i drove the car i noticed that in high rpms the knock knock gets weaker and weaker but lots of white smoke comes from tailpipe during acceleration. Also there is a huge power loss but the turbo still produces boost.

What do you guys think I ruined, except my day and my wallet ?
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Old 11-22-2008, 09:54 AM
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maybe blew a hole in a piston or fuxored a ring or valve.
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Old 11-22-2008, 10:14 AM
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Old 11-22-2008, 10:19 AM
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Just out of curiosity, why would you turn the boost up to 17psi with an EMB and 305cc injectors?
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Old 11-22-2008, 10:22 AM
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Originally Posted by paul
maybe blew a hole in a piston or fuxored a ring or valve.
If that its true , is it from the power or the poor management ?

I ran 11:1 the moment it failed without knocking.
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Old 11-22-2008, 10:24 AM
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Originally Posted by gianic
If that its true , is it from the power or the poor management ?

I ran 11:1 the moment it failed without knocking.
My sig can answer that question.


How are you maintaining an 11:1 AFR at those boost levels with 305's? I don't see anything about an AFPR.
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Old 11-22-2008, 10:30 AM
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Originally Posted by paul
My sig can answer that question.


How are you maintaining an 11:1 AFR at those boost levels with 305's? I don't see anything about an AFPR.
I dont use an afpr, these readings are what zeitronix was showing. I guess that either the injectors are underrated or zeironix doesn't show up the right values.
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Old 11-22-2008, 10:42 AM
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My vote is against the supra injectors being underrated by that much. Did you happen to be logging when this happened?
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Old 11-22-2008, 10:47 AM
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Originally Posted by paul
My vote is against the supra injectors being underrated by that much. Did you happen to be logging when this happened?
Unfortunetaly no. My eyes was centered at the a/f zei gauge during the failure and my afrs were from 10.5 to 11.7:1.
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Old 11-22-2008, 10:48 AM
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Do you have 255HP fuel pump? All I've heard about the '99 is the lack of maintaining fuel pressure in high RPMs without one.

Coupled with 305cc injectors, it is impossible with the stock fuel system to support more than 230BHP. ...that's only around 195rwhp.

If your wideband was at 11:1, then your tune had major issues where you could not make a lot of power even with a **** ton of boost. So poor ignition timing, restrictions, extra heat, etc.

The noise you hear is more than likely your ringlands bouncing around.
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Old 11-22-2008, 10:57 AM
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Originally Posted by Braineack
Do you have 255HP fuel pump? All I've heard about the '99 is the lack of maintaining fuel pressure in high RPMs without one.

Coupled with 305cc injectors, it is impossible with the stock fuel system to support more than 230BHP. ...that's only around 195rwhp.

If your wideband was at 11:1, then your tune had major issues where you could not make a lot of power even with a **** ton of boost. So poor ignition timing, restrictions, extra heat, etc.

The noise you hear is more than likely your ringlands bouncing around.
I m pretty messed up with my failure and i forgot to mention something.

After 5k rpms the boost keeps dropping and dropping and dropping until 6 psi at redline. My bad. Sorry I think this is the reason that my afrs are good up there.
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Old 11-22-2008, 11:22 AM
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well now it makes more sense. Duty cycle is a lot lower at 5k then it is at redline. I can see 305s running an 11:1 AFR at 7k at only 6psi.
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Old 11-22-2008, 11:30 AM
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From your experience Braineack and Paul do you suggest me to reinforce the engine with forged internals or just repair it with stock parts?

And something else. Idle runs rock solid at 900 rpms, And car revs freely.
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Old 11-22-2008, 11:35 AM
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I would read a bit more if I were you #1. It depends on what your goals are. If you want 350+ you should build the motor. Below that the stock block can handle it with a good tune. Either way if you do some stupid **** like this again you'll blow your **** up. So read.
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Old 11-22-2008, 11:45 AM
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Originally Posted by johndoe
I would read a bit more if I were you #1. It depends on what your goals are. If you want 350+ you should build the motor. Below that the stock block can handle it with a good tune. Either way if you do some stupid **** like this again you'll blow your **** up. So read.
I feel so damn noob. When I was building the car I promised to my self that i wouldnt run over 12 psi. I hold my promise until the time I installed the incabin mbc ****.. That was my disaster!
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Old 11-22-2008, 12:31 PM
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right now you should do a leakdown test to determine what failed exactly.
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Old 11-22-2008, 12:47 PM
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If you can't keep a promise to yourself, then you definitely need use forged parts on a rebuild.
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Old 11-22-2008, 01:29 PM
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Originally Posted by m2cupcar
If you can't keep a promise to yourself, then you definitely need use forged parts on a rebuild.
That would be wise and cost effective in the future

Brain i m seeking right now the posts for the tests.
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Old 11-25-2008, 10:55 AM
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Right now I have this. Tomorrow i ll post and the rods condition. Any recommendations accepted.

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Old 11-25-2008, 10:56 AM
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Sorry about the quality guys its from my mobile.
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