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 ?

maybe blew a hole in a piston or fuxored a ring or valve.

Just out of curiosity, why would you turn the boost up to 17psi with an EMB and 305cc injectors?

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.

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.

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.

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 shit 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.

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.

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.

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 shit like this again you'll blow your shit 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 shit.. That was my disaster!

right now you should do a leakdown test to determine what failed exactly.

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.

Right now I have this. Tomorrow i ll post and the rods condition. Any recommendations accepted.

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Sorry about the quality guys its from my mobile.

Did you do a leakdown test? From this picture it looks like your downpipe is covered in oil...was your manifold coated in oil (rings)?

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Take better pictures for better analysis.

I thought having a sensor that close to the exhaust source would kill it in short order too? Shouldn't it be as close to the beginning of the cat as possible?

No leakdown test ,because here in Greece stupid engineers dont know shit about this.

Downpipe has a huge amount of oil in it.

This is the narrowband, wideband is just before the decat pipe.

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what's that in the coolant galley?

Is the vertical scoring as apparent in real life as it is in this picture?

I've been in your shoes. Now is the rebuilding stage. Decide how much power you want because you'll only want to do this once. If your looking at pushing 350 rwhp or have a good budget, go with forged internals. If your looking for modest power, you can do a rebuild on the cheap.

That engine is done. Either go get another one from the junkyard or spend a lot on machine work. Whichever is cheaper and easier. If money is plentiful, build it up stronger. That galling on the cylinder wall means that little pieces of piston and maybe rings went through your turbo's exhaust turbine also. Inspect for possible damage. Any pieces may be trapped in front of your cat. Expensive lesson to teach you some restraint. Unfortunate. If you don't have a knock sensor, that may be a helpful investment also...

Some of the valve reliefs on your pistons are very shiny compared to others. Are you seeing evidence of contact there?

I dont know what are you talking about exaclty.

No its opposite scoring.

So guys, i have 2 choices if the engine block can be fixed with overbore pistons.

1. Rebuild with forged internals. (I m wondering if m.tuned rods are ok.)I m thinking of m-tuned rods with wiseco overbore pistons (how much overbore ?)
(off topic)


2.Used motor with thicker head gasket for lower compression.

m-tuned rods are fine.

you don't want a thicker headgasket or lower compression. Paul's making over 300hp on a stock '99 1.8.

1. Fine if you want to spend the $.

2. Don't need thicker head gasket. Lots of people run with the stock head gasket. Just a bit less boost, proper fuel, timing and you will be fine.

It's strictly an economic decision for you.

Hello again! I ordered wiseco pistons with 0.50mm overbore and eagle h-beam rods. How much hp will my engine be able to handle with this setup?

The machinery shop asks 550$ for overboring and fitting the parts. Also I m selling the gt2560 for a gt2876. That failure wasnt so bad at last...

go with the 2871 over the 2876

blew the welds on the intake? jk. Same weird shit happend with my integra that was jrsc, never took it apart, swapped it and it was fine

Have you considered bigger injectors as well?

I have a forged motor, 550 injectors, gt2860rs, and I'm afraid to put it past 10psi without getting it to a dyno. lol

That price for machine work is awesome...just make sure you pick a good one.

lol I would've blown up by now with that kind of "safety buffer" :)

No need for upgrading the injectors as I m going to work it out with an 8 injectors setup. So 305s+245s= 550s . Brain why do you suggest the 2871 over the 2876 ?
I found one 2876 for cheap.

Single injectors would be much more efficient, easier to manage (not to mention install), and support the factory flow characteristics.

The stock injectors are placed where they are for a reason (like placing fuel into the airflow right before the intake valves, and at the proper angle.

Messing with this probably won't turn out ideal, unless you're doing flow analysis on your custom manifold (some have actually done this).

Maybe you are right but this is done on a miata before, so i m not reinventing the wheel hopefully.

Beside this I m running an emanage with the injector restrictions we all know.

the compressor wheel is oversized for the turbine.


it's a combo of a T04E compressor on a GT28 turbine....The 2871 will perform just as well, most likely with better spool characteristics.