What do you think of this? Fuel starve?

[boosted2000si]

I tore my motor apart and this is what I find. ALL drivers side pistons melted/started to melt the upper ringlands. Passenger side perfect. One of the rings actually broke on the #7? rear drivers side piston.

Why do you think the drives side did this and passenger side didnt? I am thinking maybe all the fuel is being pulled into the passenger rail cause it to lean out the drivers side? AF where always good but I only have 1 wideband on it in the downpipe.

 

[boosted2000si]

danny.avi - Car Videos on StreetFire


Im pretty sure it was from this night of fun lol blazer smoked my ass.

 

[Bad03Vert]

Do you have the head cooling mod done?

 

[CanuckSnake]

danny.avi - Car Videos on StreetFire


Im pretty sure it was from this night of fun lol blazer smoked my ass.

Whats up with the Blazer???? How are the cylinders?

 

[boosted2000si]

Whats up with the Blazer???? How are the cylinders?

Stupid fast, just running for fun we knew how it was going to play out.

Walls are fine.

 

[Jimmysidecarr]

I am more inclined to think that ECT was hotter in the driver side head.

Normally a lean out detonation event will hurt one or two on both sides, at least it seems that way most often.
EDIT : But I am at a little bit of a disadvantage here because I do not know any of your mods.

 

[boosted2000si]

I am more inclined to think that ECT was hotter in the driver side head.

Normally a lean out detonation event will hurt one or two on both sides, at least it seems that way most often.
EDIT : But I am at a little bit of a disadvantage here because I do not know any of your mods.

It was all of the driverside pistons that got damaged, I only took a photo of the 2.

Pretty much just an all done up Turbo Car. But just the standard fuel mods. Stock rails and lines, upgraded pumps and injectors. I was running around 15-19 psi depending on the mood.

 

[Jimmysidecarr]

Why do you think the drives side did this and passenger side didnt?

Is it possible there is more back pressure on the driver's side?
Is the intake manifold of a type or plumbed in a way, that at higher boost the air can blow in and stack up more on one side than the other?
Like on an 01 where the air comes in on the passenger side? I don't know if a side entry intake would allow one side to be favored by the inertia of the air or not.
I do know that many of the very high boost turbos use an intake like a Sullivan which is center inlet and are know for very even distribution even with wet/carbed draw through applications.
Maybe an oddity of a side inlet N/A intake showing uneven distribution is a stretch.

I am thinking maybe all the fuel is being pulled into the passenger rail cause it to lean out the drivers side?

If the fuel rail inlet was on the passenger side like on a Terminator intake/fuel rail and the crossover hose had an internal wall failure(or leak) it could potentially restrict the driver side supply. You would know about a leak, you would not know about an internal wall failure. The problem is, I do not think the silicone appearing fuel cross over hose is even of a laminated multi-wall design,(like most fuel hose) which means it could not come apart and plug itself internally.
If the hose became kinked or compressed some how, it could restrict the left side feed.

AF where always good but I only have 1 wideband on it in the downpipe.

There have been cases of PCM failure, where one whole bank of injectors are no longer driven. I am not aware if that condition is known to ever be intermittent however.
If one whole bank went lean, even a single wide band in a collective single down pipe, would read a lean condition unless the passenger side was extraordinarily rich enough to mask it.

Detonation we know happened, the piston and ring damage is from the higher temps of detonation heat, and would have made them grow out and contact the walls.
We just don't know what caused the detonation for sure.
We know it couldn't be octane, because that would remain constant side to side.
Fuel distribution is possible but it would almost have to be bank failure (of the injector drivers)in the PCM.
If the cross over hose checks out OK on the rail, then the rail becomes unlikely too.

Then we have to look at engine temp. We already know that these engine CAN get hot in the left head, even with the head cooling mod.
What was the sequence of events just prior to the damage event?
Was there more than one pull? How far up through the gears?
The possibility that the detonation may have been caused by a localized series of left bank hot spots, I do not think can be totally ruled out.

 

[boosted2000si]

Is it possible there is more back pressure on the driver's side?
Is the intake manifold of a type or plumbed in a way, that at higher boost the air can blow in and stack up more on one side than the other?
Like on an 01 where the air comes in on the passenger side? I don't know if a side entry intake would allow one side to be favored by the inertia of the air or not.
I do know that many of the very high boost turbos use an intake like a Sullivan which is center inlet and are know for very even distribution even with wet/carbed draw through applications.
Maybe an oddity of a side inlet N/A intake showing uneven distribution is a stretch.



If the fuel rail inlet was on the passenger side like on a Terminator intake/fuel rail and the crossover hose had an internal wall failure(or leak) it could potentially restrict the driver side supply. You would know about a leak, you would not know about an internal wall failure. The problem is, I do not think the silicone appearing fuel cross over hose is even of a laminated multi-wall design,(like most fuel hose) which means it could not come apart and plug itself internally.
If the hose became kinked or compressed some how, it could restrict the left side feed.



There have been cases of PCM failure, where one whole bank of injectors are no longer driven. I am not aware if that condition is known to ever be intermittent however.
If one whole bank went lean, even a single wide band in a collective single down pipe, would read a lean condition unless the passenger side was extraordinarily rich enough to mask it.

Detonation we know happened, the piston and ring damage is from the higher temps of detonation heat, and would have made them grow out and contact the walls.
We just don't know what caused the detonation for sure.
We know it couldn't be octane, because that would remain constant side to side.
Fuel distribution is possible but it would almost have to be bank failure (of the injector drivers)in the PCM.
If the cross over hose checks out OK on the rail, then the rail becomes unlikely too.

Then we have to look at engine temp. We already know that these engine CAN get hot in the left head, even with the head cooling mod.
What was the sequence of events just prior to the damage event?
Was there more than one pull? How far up through the gears?
The possibility that the detonation may have been caused by a localized series of left bank hot spots, I do not think can be totally ruled out.

All are very valid points and I will probably need to look at that cross over fuel line. The car never ran bad or had a hiccup where I would think you would be able to tell if the whole bank failed(pcm.)

I do NOT have a head cooling mod, and that was also one of the very first things I thought of but I thought that was more for the head its self. However with the head heating up it may have allowed the pistons to heat up just enough to cause this damage.

From the night I think the damage was cause till the time the engine was pulled was probably 7 months and about 1500 miles later. The car ran decent all the way up till the time it was pulled, I pulled the motor cause the compression test came back horrible, as you could see lol.

I am going to send all the injectors up to Steg to be flowed ported and to ensure they are all on the same page.

I am running just a stock 01 intake, stock heads, pretty much just a stock longblock. I had cometic gaskets and arp head studs but nothing more than that.

I am really considering adding an additional wideband to the drivers bank and moving the one from off the down pipe to the passenger bank and being able to read each side. I really dont want this to be an issue again. I know the factory pistons are a little weak but no reason I should melt all 4 like this.

 

[Jimmysidecarr]

I am going to send all the injectors up to Steg to be flowed ported and to ensure they are all on the same page.

I am running just a stock 01 intake, stock heads, pretty much just a stock longblock. I had cometic gaskets and arp head studs but nothing more than that.

I am really considering adding an additional wideband to the drivers bank and moving the one from off the down pipe to the passenger bank and being able to read each side. I really dont want this to be an issue again. I know the factory pistons are a little weak but no reason I should melt all 4 like this.

I like these ideas.

I would also mark each injector with the cyl # and ask for the flow test results before the upgrade to 80s, just so you know.

I think a turbo will do a little better with a nice set of 2618 alloy pistons and a bit more PTW clearance.

Perhaps price a dual bank EGT gauge set up also, it's very nice to have on an adjustable boost, high power set up.:beer: