Piston Issues Confirmed..I Think.

[Prof]

Well I am way over my head here...need some people with a lot more grease under their finger nails than I have.

But in the pictures below there seems to be some pretty strong evidence of a design flaw in our stock pistons...so take a moment to study the evidence as I see it.

Picture #1 is from what would be the drivers side of the engine with the pistons arrayed in correct sequence...and nothing looks wrong (I have removed the comprehension rings...)

Picture #2 is a closer look at pistons 1-5...

Picture #3 is a closer look at 6 - 10, still looking pretty good.

Now Picture # 4 is an over all shot of all ten pistons from the passenger side...

Picture # 5 and #6...Now there is some damage!

Note that all the ring land destruction is on the same side and begins at the same point...

If I were to reverse the piston domes for six more pictures you would see that the out side ring land on all ten pistons is damaged in the same way!

When my engine was disassembled every piston had cracks in the lands...once the pistons were pulled from the sleeves...the lands fell apart...and what you see is where I have pulled all of the cracked lands out after removing the compression rings.

I think that we see in my ten pistons that the outside of our pistons for some reason crack the lands...which can then lead to pieces falling out, and destroying engines...I may have been minutes away from Boom...

Any other conclusions from some of you wrenches???

 

[JTS VENOM PERFORMANCE]

I aint say nuttin...............

 

[Prof]

Close-up of missing divider between the two compression rings...sheared off at the same place in every piston.

 

[Prof]

I aint say nuttin...............

That doesn't help anyone.

 

[Manic]

Great pics, Roy! You were so close to losing your engine...

 

[Prof]

It is just amazing to me that every piston has the same issue in exactly the same spot!

 

[Manic]

Sorry, I forgot to ask if there was any damage to the block?

Also, what did you have the red line set to when you were 'playing' with it after the Roe?

Wil

 

[Demon 8]

This is scary
Sorry I am still new...were you boosted or stock

 

[LitemUp]

WOW!

 

[Ram From Hell]

Most of my pistons came out the same way. Here's a profile of #3.

I can only guess that this point is somehow where the stress from detonation is the highest, or the greatest blow by in the cylinder is occurring at this spot.

It can't be said enough that these pistons in these engines do NOT respond well to cylinder pressures much greater than stock, and respond even worse to detonation.

 

[supercar1of1]

It is just amazing to me that every piston has the same issue in exactly the same spot!

Prof you posted along time ago that you thought the pistons were the problem and after some of the other guys problems it pretty much looked to
be the case.
These new photo's IMO positively remove any doubt that Dodge installed
defective parts in our engines and should step up to the plate with some sort
of support for us.
BTW: how many miles were on your engine?








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[nycstev]

A fine piece of detective work Roy. What would cause failure? Overheating and stress? But why?

 

[LitemUp]

Can someone explain to me why most of the engines that have been lost have had the Roe SC, and why are the Paxton SC not failing as often. :dontknow: Is it because of the nature of how the boost kicks in? :dontknow:

Don't get me wrong I am by no means knocking the Roe SC. I would just like to understand why this is occuring more frequently on those blowers?

 

[nycstev]

Can someone explain to me why most of the engines that have been lost have had the Roe SC, and why are the Paxton SC not failing as often. :dontknow: Is it because of the nature of how the boost kicks in? :dontknow:

Don't get me wrong I am by no means knocking the Roe SC. I would just like to understand why this is occuring more frequently on those blowers?

HEY!!! WTF ARE YOU KNOCKING THOSE ROE UNITS FOR!!!!!

 

[supercar1of1]

Can someone explain to me why most of the engines that have been lost have had the Roe SC, and why are the Paxton SC not failing as often. :dontknow: Is it because of the nature of how the boost kicks in? :dontknow:

Don't get me wrong I am by no means knocking the Roe SC. I would just like to understand why this is occuring more frequently on those blowers?

That question could not be answered without knowing how many of each type were out there and the amount of use/driving style each were exposed to.







.

 

[JTS VENOM PERFORMANCE]

Prof you posted along time ago that you thought the pistons were the problem and after some of the other guys problems it pretty much looked to
be the case.
These new photo's IMO positively remove any doubt that Dodge installed
defective parts in our engines and should step up to the plate with some sort
of support for us.
BTW: how many miles were on your engine?









.

this is why prof...................Eric explained it best, I didnt have to......

 

[supercar1of1]

this is why prof...................Eric explained it best, I didnt have to......

? Do What?





.

 

[Prof]

Sorry, I forgot to ask if there was any damage to the block?

Also, what did you have the red line set to when you were 'playing' with it after the Roe?

Wil

No damage to block, rods, crank or anything...just piston land between the two compression rings. Every piston had exactly the same cracks in the same location...had a piece or two come out...it would have dusted the engine. I think I caught it just before BOOM. My Raptor has never been over 5600.

This is scary
Sorry I am still new...were you boosted or stock

I am boosted...running 5.6 lbs of boost...certainly part of the matrix.

Most of my pistons came out the same way. Here's a profile of #3.

I can only guess that this point is somehow where the stress from detonation is the highest, or the greatest blow by in the cylinder is occurring at this spot.

It can't be said enough that these pistons in these engines do NOT respond well to cylinder pressures much greater than stock, and respond even worse to detonation.

I have no signs of detonation, and the plugs were clean too (no deposits from detonation). And I think your assumption to higher cylinder pressure is a contributing factor to piston failure...but I have no evidence to support that assumption.

Prof you posted along time ago that you thought the pistons were the problem and after some of the other guys problems it pretty much looked to
be the case.
These new photo's IMO positively remove any doubt that Dodge installed
defective parts in our engines and should step up to the plate with some sort
of support for us. BTW: how many miles were on your engine?
.

I can't support your conclusion. I am a FI engine, that says that there is no evidence from my experience that a normally aspirated engine would have any problems...Forced Induction raises lots of different issues...temperatures, pressures, air/fuel mixtures, water/meth...just lots of things that stock engines do not encounter...so I don't think you can extrapolate my problem to all pistons...but there is a strong leaning in that direction.

A fine piece of detective work Roy. What would cause failure? Overheating and stress? But why?

Steve you are the engineer...but it seems to me that heat would cause failures at lots of different places...but since the failure in all ten pistons was at the same place...I am leaning toward stress at that point in the land divider...which could be exacerbated by the failure of the piston dome to dissipate heat...but we need the engineers to opine here...I am a pompous pontificater (read professor) not an engineer.

Can someone explain to me why most of the engines that have been lost have had the Roe SC, and why are the Paxton SC not failing as often. :dontknow: Is it because of the nature of how the boost kicks in? :dontknow:

Don't get me wrong I am by no means knocking the Roe SC. I would just like to understand why this is occuring more frequently on those blowers?

I love my Roe, and I think Sean Roe is the salt of the earth...so I may be very biased...but in my mind this is an engine problem not a supercharger issue.

 

[supercar1of1]

No damage to block, rods, crank or anything...just piston land between the two compression rings. Every piston had exactly the same cracks in the same location...had a piece or two come out...it would have dusted the engine. I think I caught it just before BOOM. My Raptor has never been over 5600.



I am boosted...running 5.6 lbs of boost...certainly part of the matrix.



I have no signs of detonation, and the plugs were clean too (no deposits from detonation). And I think your assumption to higher cylinder pressure is a contributing factor to piston failure...but I have no evidence to support that assumption.



I can't support your conclusion. I am a FI engine, that says that there is no evidence from my experience that a normally aspirated engine would have any problems...Forced Induction raises lots of different issues...temperatures, pressures, air/fuel mixtures, water/meth...just lots of things that stock engines do not encounter...so I don't think you can extrapolate my problem to all pistons...but there is a strong leaning in that direction.



Steve you are the engineer...but it seems to me that heat would cause failures at lots of different places...but since the failure in all ten pistons was at the same place...I am leaning toward stress at that point in the land divider...which could be exacerbated by the failure of the piston dome to dissipate heat...but we need the engineers to opine here...I am a pompous pontificater (read professor) not an engineer.



I love my Roe, and I think Sean Roe is the salt of the earth...so I may be very biased...but in my mind this is an engine problem not a supercharger issue.

The reason I purchased the SRT-10 is because my other vehicle(the blown
Town Car) is constantly breaking something(tires,trans,rear), and I decided to
buy something that was supposed to be designed to run hard to begin with.

It was not until after the purchase and scouring this and some other web sites that it appeared that the flag ship component of these trucks may not
be built to the durability level one would take for granted when contemplating a purchase.
FYI: My 5.4 DOHC is stone stock but pushing 15psi boost for 36,000 hard miles, with one oil change and has not used a drop of oil.


Bottom line, an engine advertised as probably the ultimate exotic special

high performance engine that probably added $20k+ to the price IMO,

should be expected to live at the same HP/ci displacement as a $3,150.00

non HP crate motor, especially when you look at the number of years

they have had to get it right!








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[bigike]

Just CANT boost a stock internal engine.