Piston Issues Confirmed..I Think.

[supercar1of1]

I hear ya.I doubt you would have an issue,.but the price of ownership is what it is..If you didnt know that someday you would be replacing the clutch, or buying an SCT, or whatever, well then you didnt do your homework first..The piston issue is a relatively cloudy issue..not many have shared as Prof has with his pics..We hear of an oiling issue with #3 piston, and things like that, and have discussed the ring land/ piston issue to some degree..Prof is FI, and tore his motor down to forge it based on what he believes is a problem..He wants his 14sec monster to last for awhile..lol..He is a smart man..I tend to agree with his thinking..

Sorry Roy..not trying to speak for you or dominate your thread here..

Prof is the one that mentioned the pistons first if my memory serves, and after seeing haulinasps picks and a few more, then profs latest pic's, I think
that the pistons are 95%+ the issue. 5-6 psi like prof and some others were
running is nothing(comparatively) speaking.

 

[Blaine@PSI]

I will give you my take on it and take it with a grain of salt but here goes.

First off I see 2 problematic area here. one being the ring land and it distance between the top and second ring. That distance is allowing a build of "gases" thus deteriorating the amount of aluminum between the two. Also ring gap is to close together for bosted or raised compression levels to accomodate those higher pressures. I believe that once measured out on a stock engine you will find a ring gap of about 3-4.5 thousandths which does not give any room for error(tune) and therefore with increased pressure levels will cause a ring to "stick" thus crushing or lifting a ring land causing the damage you have pictured here on the first page. Pounding the ring land time and time again will show these signs and eventually lead to engine failure. Thats why a tune is extremely critical and should not be taken lightly at any cost. I do not even think that a motor of this caliber should have increased pressure in the form of combustion. And I also believe that the ring gap should be 5-7thousandths for a Forced Inducted motor to forgive the amount of growth expected under severe load such as racing of dyno pulls or simply passing some or getting on the freeway.

Now onto my next observation of the Roe Vs. Paxton. My take and opinion is that this corealation between the 2 and the amount of failure stems from intercooled and non intercooled F.I. Increasing cylinder pressure and adding heat is the 2 most deadliest variables to introduce to a internal combustion engine. mointoring those and reducing timing, increasing octane and lowering heat range on a spark plug can help aid into the survival of said motor but one slip and it is done. Now I can go on and on but will stop here and in hopes maybe put some insight into whats my opinions are and cause of a failed pistons in these engines. I will not get into the oiling system nightmare dodge engineers left us with to deal with but know that they are issues as well contributing to the failures.....


I done, its to late

 

[supercar1of1]

I will give you my take on it and take it with a grain of salt but here goes.

First off I see 2 problematic area here. one being the ring land and it distance between the top and second ring. That distance is allowing a build of "gases" thus deteriorating the amount of aluminum between the two. Also ring gap is to close together for bosted or raised compression levels to accomodate those higher pressures. I believe that once measured out on a stock engine you will find a ring gap of about 3-4.5 thousandths which does not give any room for error(tune) and therefore with increased pressure levels will cause a ring to "stick" thus crushing or lifting a ring land causing the damage you have pictured here on the first page. Pounding the ring land time and time again will show these signs and eventually lead to engine failure. Thats why a tune is extremely critical and should not be taken lightly at any cost. I do not even think that a motor of this caliber should have increased pressure in the form of combustion. And I also believe that the ring gap should be 5-7thousandths for a Forced Inducted motor to forgive the amount of growth expected under severe load such as racing of dyno pulls or simply passing some or getting on the freeway.

Now onto my next observation of the Roe Vs. Paxton. My take and opinion is that this corealation between the 2 and the amount of failure stems from intercooled and non intercooled F.I. Increasing cylinder pressure and adding heat is the 2 most deadliest variables to introduce to a internal combustion engine. mointoring those and reducing timing, increasing octane and lowering heat range on a spark plug can help aid into the survival of said motor but one slip and it is done. Now I can go on and on but will stop here and in hopes maybe put some insight into whats my opinions are and cause of a failed pistons in these engines. I will not get into the oiling system nightmare dodge engineers left us with to deal with but know that they are issues as well contributing to the failures.....


I done, its to late

Bullseye! Man you just saw what a bunch of us just overlooked, the dad gum
RING GAP!! If the ring gap is tight it dosn't take much extra heat and they will SEIZE! That solves it for me. I bet since they had problems with cold start blow by they also set the ring gap on the snug side, which would totally
explain the issue.:congrats: :congrats: :congrats:

Man great observation! If we ever cross paths I'll get the check!:rock:


I'm glad that wasn't a snake, a bunch of us that should have seen that would be bit!






.

 

[Blaine@PSI]

thanks I am little squirt in years persay but my dad taught me a great deal on boosted engines. he owned a Buick GN back in the day some 25yrs ago nearly. So I got my "grass roots" from him.

 

[supercar1of1]

thanks I am little squirt in years persay but my dad taught me a great deal on boosted engines. he owned a Buick GN back in the day some 25yrs ago nearly. So I got my "grass roots" from him.

Well you sure nailed it! That should have been obvious to a bunch of us, and I
am sure that I am not alone thinking how in the world I could have overlooked
somthing that elemental.

Again:congrats: :congrats: :congrats: :congrats:


.

 

[SrtBrad]

Prof thanks for posting this detailed thread with pictures. What was your compression at before you decided to go forged. How much oil was getting into the catch can. What other clues can you tell everyone to look out for so they know when to stop before it's too late and do a forged rebuild.

I will be taking out my 05 QC engine that was NA but spun a rod in the next 2-3 weeks. When I take the engine apart I will also take detailed pics like yours and see what my pistons look like after 41K hard miles. This should be an interesting comparison.

 

[the bowler]

do you guys think that adding the computer from dodge to a stock motor would be chancing it, based on what you guys have shown? cause i wanna do SOMETHING to my truck, but cant decide between the computer or rear diff gears as a cheaper upgrade. :dontknow:

 

[Prof]

...First off I see 2 problematic area here. one being the ring land and it distance between the top and second ring. And I also believe that the ring gap should be 5-7thousandths for a Forced Inducted motor to forgive the amount of growth expected under severe load such as racing of dyno pulls or simply passing some or getting on the freeway...

Now onto my next observation of the Roe Vs. Paxton. My take and opinion is that this corealation between the 2 and the amount of failure stems from intercooled and non intercooled F.I.

Both items are to be considered. But why in your mind, did each piston land break in the same spot?

Let's keep the ideas coming. This kind of discussion can only help all of us.

 

[bigike]

Just CANT boost a stock internal engine.

 

[Prof]

Would you like any cheese with your whine? Honestly I can't ever see you getting anywhere with Dodge on any kind of compensation from this piston issue. What really strikes me as silly is when I read about people who spend upwards of almost 10 G's for a mere 5-6 lbs. of boost. Bottom line, Do Not Mod these engines because it's not worth it.

I concur that Dodge will be reticent to address this issue and that is not the intent of this thread. We are trying to address an issue that seems to be chronic in these engines.

Why 5-6 lbs of boost? You must have never driven a Roe Supercharged truck...or you are used to 20 or 25 lbs of boost on a Supra...

My truck was the prototype street Roe install. I am an early adopter and lived very close to Sean Roe who did the install and tuned the engine himself. My request was for a street quick machine, not a racing vehicle. I achieved that...there are only one or two people who know what my truck's best E.T. was with 5.6 lbs of boost...and it will stay that way, because it is a street truck...but I will say that, the horse power weight conversion tables are very close to my experience.

I do agree with you that if your idea is to have the fastest vehicle in town this is not the vehicle to mod. But if you love MOPAR trucks, the Viper image and everything these trucks are...as most of us do...then mod away after reading all you can about others experience. I don't think that anyone who mods a 5200 lb vehicle is trying to be the fastest...just trying to make something that is very good better.

Welcome to the site, and enjoy your ride...we are just trying to shed some light on this issue.

 

[bigike]

Blaine is the MAN a plethora of knowledge!

Hell of a hand!

 

[Prof]

do you guys think that adding the computer from dodge to a stock motor would be chancing it, based on what you guys have shown? cause i wanna do SOMETHING to my truck, but cant decide between the computer or rear diff gears as a cheaper upgrade. :dontknow:

I think Jay is really responding to your question...I would not hesitate to flash the cpu, modify the exhaust or change the differential ratio...all should be safe.

And I think Stinker suggested something yesterday that is inspired thinking...a small shot of spray, say a 50 shot, should be looked at as an engine safety mod rather than a performance enhancer...that was some real inspired out of the box thinking!

 

[SRT10VENOMOUS]

Would you like any cheese with your whine? Honestly I can't ever see you getting anywhere with Dodge on any kind of compensation from this piston issue. What really strikes me as silly is when I read about people who spend upwards of almost 10 G's for a mere 5-6 lbs. of boost. Bottom line, Do Not Mod these engines because it's not worth it.

your obviously a homo.. please leave... thank you

 

[supercar1of1]

Both items are to be considered. But why in your mind, did each piston land break in the same spot?

Let's keep the ideas coming. This kind of discussion can only help all of us.

The pistons broke in the same spot because the rings were equally over heated and tried to seize at approx; the same spot in the stroke.
This pretty much lets Dodge off the hook as far as I am concerned, unless
we can document the same thing in some unblown/NO2 engines.




.

 

[FastRam]

I will give you my take on it and take it with a grain of salt but here goes.

First off I see 2 problematic area here. one being the ring land and it distance between the top and second ring. That distance is allowing a build of "gases" thus deteriorating the amount of aluminum between the two. Also ring gap is to close together for bosted or raised compression levels to accomodate those higher pressures. I believe that once measured out on a stock engine you will find a ring gap of about 3-4.5 thousandths which does not give any room for error(tune) and therefore with increased pressure levels will cause a ring to "stick" thus crushing or lifting a ring land causing the damage you have pictured here on the first page. Pounding the ring land time and time again will show these signs and eventually lead to engine failure. Thats why a tune is extremely critical and should not be taken lightly at any cost. I do not even think that a motor of this caliber should have increased pressure in the form of combustion. And I also believe that the ring gap should be 5-7thousandths for a Forced Inducted motor to forgive the amount of growth expected under severe load such as racing of dyno pulls or simply passing some or getting on the freeway.

Now onto my next observation of the Roe Vs. Paxton. My take and opinion is that this corealation between the 2 and the amount of failure stems from intercooled and non intercooled F.I. Increasing cylinder pressure and adding heat is the 2 most deadliest variables to introduce to a internal combustion engine. mointoring those and reducing timing, increasing octane and lowering heat range on a spark plug can help aid into the survival of said motor but one slip and it is done. Now I can go on and on but will stop here and in hopes maybe put some insight into whats my opinions are and cause of a failed pistons in these engines. I will not get into the oiling system nightmare dodge engineers left us with to deal with but know that they are issues as well contributing to the failures.....


I done, its to late

Bingo, give that man a prize, and prof.

 

[HaulinAsp]

The pistons broke in the same spot because the rings were equally over heated and tried to seize at approx; the same spot in the stroke.
This pretty much lets Dodge off the hook as far as I am concerned, unless
we can document the same thing in some unblown/NO2 engines.




.

No nitrous, unblown for my paper weights. I have atleast 7 pistons with the same damage.......:dontknow:

 

[eddie102870]

I think Jay is really responding to your question...I would not hesitate to flash the cpu, modify the exhaust or change the differential ratio...all should be safe.

And I think Stinker suggested something yesterday that is inspired thinking...a small shot of spray, say a 50 shot, should be looked at as an engine safety mod rather than a performance enhancer...that was some real inspired out of the box thinking!

roy we've been kicking this around for a while it started because my truck would run 2 tenths slower on the 2nd run if i didnt let it cool down. we thought about using this as a fix.i'm scared of the spray with my stock bottom end. mainly because i dont have the extra cash laying around to build it right now. these threads are really helping. sean said to make sure and run race gas at the track for added safety. wish i would have known that from the jump. no more than i drive my truck id probably keep race gas in it.

now on the ring lands. how hard would it be to have pistons made with the ring lands farther apart? i would think this wouldnt be that hard.

 

[Prof]

I have made contact with someone who is going to get the pictures and my comments into the hands of Chrysler. Not for any purpose other than contributing to the knowledge base of their engineers. I have not asked for any feedback or comment from them...just in hopes that this little bit of evidence will produce a better product for us MOPAR addicts at some point in the future.

 

[Prof]

Prof thanks for posting this detailed thread with pictures. What was your compression at before you decided to go forged. How much oil was getting into the catch can. What other clues can you tell everyone to look out for so they know when to stop before it's too late and do a forged rebuild.

I will be taking out my 05 QC engine that was NA but spun a rod in the next 2-3 weeks. When I take the engine apart I will also take detailed pics like yours and see what my pistons look like after 41K hard miles. This should be an interesting comparison.

I am not much of a mechanic...just an avid reader...I did a leak-down test because Justin recommended it after we worked on how to get a catch can to not push oil out of the breather...we decided on using stainless steel, steel wool. (Some use copper 'Chore Girl' scrubbers.) He was concerned about the amount of pressure that existed in the drivers side valve cover. (That is the side that gets the most pressure because of the rotating direction of the engine.) I had no problems from the passenger side of the engine, but those pistons were equally damaged.

It must have been down on power, but since I don't visit the track very often it was not obvious in my butt dyno...it never seemed to burn any oil...

There was some compression loss when we did the compression and leak down test...but not much difference from hole to hole...now I think I know why...my lands were cracked, but held in place by the rings and the cylinder sleeves...no chunks had come out...but they would have in short order...once the pistons were pulled...all of the piston lands fell apart...all of them! The rings were not damaged...so the compression and leak down don't tell the story! The cracks were below the top compression ring and above the bottom compression ring...so leak down and compression tests just could not see the problem...except in the happenstance that the gap in the compression rings had both lined up over one of the cracks...not much chance of that...

Soooooo...What do we do to check for this problem??? I don't know...

My recommendation...if you go FI go with forged pistons, forged rods, chrome moly push rods...and whatever else you can afford to do while the engine is apart...and then add the FI power adder...but what do I know? I don't get grease under my finger nails...it might cause those young ladies in the first row to not wear short skirts!

 

[Prof]

roy we've been kicking this around for a while it started because my truck would run 2 tenths slower on the 2nd run if i didnt let it cool down. we thought about using this as a fix.i'm scared of the spray with my stock bottom end. mainly because i dont have the extra cash laying around to build it right now. these threads are really helping. sean said to make sure and run race gas at the track for added safety. wish i would have known that from the jump. no more than i drive my truck id probably keep race gas in it.

now on the ring lands. how hard would it be to have pistons made with the ring lands farther apart? i would think this wouldnt be that hard.

We need some one to put a micrometer on a diamond piston to see what distance they have between the two compression rings...it looks (in my pictures to be about the same (http://www.vtcoa.com/forums/showthread.php?t=24264&highlight=Diamond+Pistons)...the stock pistons have two metals in the divider...I will take a close up later to show that...that could be a possible cause too...but the distance seems to be about the same...just being forged and stronger may be enough...but I don't know the engineering ramifications here...where the hell is Silverback when you need him?

Has anyone seen this piston land destruction in forged pistons????