1st pass with 5.3 = 2 broken, 1 torched piston ???
07-09-2012, 04:56 PM
#41
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Looks like it went lean, torched a few pistons, and heated the rings on the other.
I am in the progress trying to blow up my 5.3 back up motor, non intercooled, E85, 30+ deg at 19-20lbs. 60+ full hard passes later on the street and its still running fine with no blow by.
I am in the progress trying to blow up my 5.3 back up motor, non intercooled, E85, 30+ deg at 19-20lbs. 60+ full hard passes later on the street and its still running fine with no blow by.
Its alcohol, sure it doesnt have the same latent heat properties as methanol, but until someone puts a thermocoupler, or EGT sensor, something, or some mad way of reading temp inside the combustion chamber, and proves it cant do the job, im not buying.
yes, the argument can be made, denser air is better, etc. etc. But As far as melting pistons and ****, im looking at fuel between the ring lands and a glow plug for a spark plug.
Flame suit is on, so people can start flaming away, lmao. Ive got 19psi springs in my gates and im not turning back, IC or not
07-09-2012, 07:43 PM
#42
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07-09-2012, 07:46 PM
#43
Been through this before, too rich and a projected plug that was too hot. I've been preaching this for a while on here and get flamed nearly every time. I'm with Jax, I think I've rubbed off on him
Steam vents might of helped, but that piston is melted to the hilt, rich melted and lean melted can look very similar as the results are usually the same. Some just can't understand why it would melt down if it was "safe and rich".
I also would like to know how in the hell 10.2afr = "looks like it went lean"
Steam vents might of helped, but that piston is melted to the hilt, rich melted and lean melted can look very similar as the results are usually the same. Some just can't understand why it would melt down if it was "safe and rich".
I also would like to know how in the hell 10.2afr = "looks like it went lean"
07-09-2012, 07:51 PM
#44
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Thanks for posting this Max. Im not one to believe that IATs caused this, sure, it could've played a role, but i just dont see it.
Its alcohol, sure it doesnt have the same latent heat properties as methanol, but until someone puts a thermocoupler, or EGT sensor, something, or some mad way of reading temp inside the combustion chamber, and proves it cant do the job, im not buying.
yes, the argument can be made, denser air is better, etc. etc. But As far as melting pistons and ****, im looking at fuel between the ring lands and a glow plug for a spark plug.
Flame suit is on, so people can start flaming away, lmao. Ive got 19psi springs in my gates and im not turning back, IC or not
Its alcohol, sure it doesnt have the same latent heat properties as methanol, but until someone puts a thermocoupler, or EGT sensor, something, or some mad way of reading temp inside the combustion chamber, and proves it cant do the job, im not buying.
yes, the argument can be made, denser air is better, etc. etc. But As far as melting pistons and ****, im looking at fuel between the ring lands and a glow plug for a spark plug.
Flame suit is on, so people can start flaming away, lmao. Ive got 19psi springs in my gates and im not turning back, IC or not
Wouldn't the cylinder heads show signs of severe detonation? Does any of this make sense?
07-09-2012, 07:59 PM
#45
OK, could this be a result of Piston rings butting together because of excessive heat? I am thinking #7 broke all three ring lands and then melted. #1 and 5 broke the 2nd and 3rd ring lands, and five of the eight connecting rods were bent. Wouldn't the rings dragging in the bore cause the rods to bend? The piston tops on all eight pistons showed no peppering, pitting, erosion, etc. just breaks.
Wouldn't the cylinder heads show signs of severe detonation? Does any of this make sense?
Wouldn't the cylinder heads show signs of severe detonation? Does any of this make sense?
Now as far as the detonation part I'm not 100% positive on that part I'd have to see the porcelain on the plugs to see if there were any peppering on them they would tell the true tale.
The heat on that piston though reminds me of classic rich melt down, the stock rings just don't like that much heat and being run that rich so it weakens them to the point they butt, and consequently break and Yes then the rods bend when this happens also as they did on you from the rings not taking the cushion and transmitting the pressure to the rod which then can't take the pressure and bends.
Where are the pictures of the rest of the pistons do you have any? If nothing actually broke off the piston and got knocked around inside the cylinder the chance you gouged the wall is going to be lower although it can still happen.
07-09-2012, 08:10 PM
#46
Something I missed that you said also was that number 8 at the intake valve is starting to flake that is a classic sign of high IAT also as that is where the intake air is coming into the cylinder first.
Rich, high IAT's, a little too much timing for that much boost and combined with the high IAT's also all contributed to this I think as did the too hot of a plug. I think you totally skipped the detonation part and went straight into pre-ignition and you continued to feed the fire big time by over fueling it and it being on the edge timing wise.
Also the cold knock you could've heard before might of been a weak ringland that had let go and was allowing oil in there causing this to really snow ball in the combustion chamber.
Some people can get by running their cars over timed and then run them rich to cover the over timed issue up and run forever, but when one thing goes slightly wrong or starts to go it goes fast and usually ends up ugly like this especially with a projected tip sticking all the way in there lighting the mixture off that the tip temperature of that plug was too hot to begin with.
But the short is: overfueled, over timed for the IAT's and boost level's combined and too hot a plug with a projected tip.
Rich, high IAT's, a little too much timing for that much boost and combined with the high IAT's also all contributed to this I think as did the too hot of a plug. I think you totally skipped the detonation part and went straight into pre-ignition and you continued to feed the fire big time by over fueling it and it being on the edge timing wise.
Also the cold knock you could've heard before might of been a weak ringland that had let go and was allowing oil in there causing this to really snow ball in the combustion chamber.
Some people can get by running their cars over timed and then run them rich to cover the over timed issue up and run forever, but when one thing goes slightly wrong or starts to go it goes fast and usually ends up ugly like this especially with a projected tip sticking all the way in there lighting the mixture off that the tip temperature of that plug was too hot to begin with.
But the short is: overfueled, over timed for the IAT's and boost level's combined and too hot a plug with a projected tip.
07-09-2012, 08:16 PM
#47
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Something I missed that you said also was that number 8 at the intake valve is starting to flake that is a classic sign of high IAT also as that is where the intake air is coming into the cylinder first.
Rich, high IAT's, a little too much timing for that much boost and combined with the high IAT's also all contributed to this I think as did the too hot of a plug. I think you totally skipped the detonation part and went straight into pre-ignition and you continued to feed the fire big time by over fueling it and it being on the edge timing wise.
Also the cold knock you could've heard before might of been a weak ringland that had let go and was allowing oil in there causing this to really snow ball in the combustion chamber.
Some people can get by running their cars over timed and then run them rich to cover the over timed issue up and run forever, but when one thing goes slightly wrong or starts to go it goes fast and usually ends up ugly like this especially with a projected tip sticking all the way in there lighting the mixture off that the tip temperature of that plug was too hot to begin with.
But the short is: overfueled, over timed for the IAT's and boost level's combined and too hot a plug with a projected tip.
Rich, high IAT's, a little too much timing for that much boost and combined with the high IAT's also all contributed to this I think as did the too hot of a plug. I think you totally skipped the detonation part and went straight into pre-ignition and you continued to feed the fire big time by over fueling it and it being on the edge timing wise.
Also the cold knock you could've heard before might of been a weak ringland that had let go and was allowing oil in there causing this to really snow ball in the combustion chamber.
Some people can get by running their cars over timed and then run them rich to cover the over timed issue up and run forever, but when one thing goes slightly wrong or starts to go it goes fast and usually ends up ugly like this especially with a projected tip sticking all the way in there lighting the mixture off that the tip temperature of that plug was too hot to begin with.
But the short is: overfueled, over timed for the IAT's and boost level's combined and too hot a plug with a projected tip.
07-09-2012, 08:31 PM
#48
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Something I missed that you said also was that number 8 at the intake valve is starting to flake that is a classic sign of high IAT also as that is where the intake air is coming into the cylinder first.
Rich, high IAT's, a little too much timing for that much boost and combined with the high IAT's also all contributed to this I think as did the too hot of a plug. I think you totally skipped the detonation part and went straight into pre-ignition and you continued to feed the fire big time by over fueling it and it being on the edge timing wise.
Also the cold knock you could've heard before might of been a weak ringland that had let go and was allowing oil in there causing this to really snow ball in the combustion chamber.
Some people can get by running their cars over timed and then run them rich to cover the over timed issue up and run forever, but when one thing goes slightly wrong or starts to go it goes fast and usually ends up ugly like this especially with a projected tip sticking all the way in there lighting the mixture off that the tip temperature of that plug was too hot to begin with.
But the short is: overfueled, over timed for the IAT's and boost level's combined and too hot a plug with a projected tip.
Rich, high IAT's, a little too much timing for that much boost and combined with the high IAT's also all contributed to this I think as did the too hot of a plug. I think you totally skipped the detonation part and went straight into pre-ignition and you continued to feed the fire big time by over fueling it and it being on the edge timing wise.
Also the cold knock you could've heard before might of been a weak ringland that had let go and was allowing oil in there causing this to really snow ball in the combustion chamber.
Some people can get by running their cars over timed and then run them rich to cover the over timed issue up and run forever, but when one thing goes slightly wrong or starts to go it goes fast and usually ends up ugly like this especially with a projected tip sticking all the way in there lighting the mixture off that the tip temperature of that plug was too hot to begin with.
But the short is: overfueled, over timed for the IAT's and boost level's combined and too hot a plug with a projected tip.
Is a TR6 a projected tip plug? What would you recommend for a good plug?
Here is a pic of a plug out of my engine. It shows no signs of detonation, like you said it could have just went into pre ignition.
07-10-2012, 11:46 AM
#54
BR7EF in all the E85 cars I tune. I tune for WOT around 11.2-11.6 on the gasoline scale and upwards of 20* of timing. And I always keep picking up power as I lean it out even up towards 12:1. That's intercooled though. Sounds like you just a few bad things add up to a a big mess.
But short blocks are cheap
But short blocks are cheap
07-10-2012, 03:30 PM
#56
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07-10-2012, 04:59 PM
#57
I tore apart an '06 GTO LS2 shortblock that had #7 issues with compression 15% lower than the others and was consuming oil. It had a rear mount turbo setup. 46K miles on it.
Ended up finding this when I removed the piston..... no deep scoring in the bore which was a plus.
Ended up finding this when I removed the piston..... no deep scoring in the bore which was a plus.
07-10-2012, 09:51 PM
#59
Rings butted, bent the rods. One failure leads to another.
The autolite plugs are a bit different to read than an NGK, but from what I can see that plug looks HOT! An autolite doesn't have the cadium plating on it that the NGK does so it doesn't get ashy color as the cadium begins to burn off and then turn light yellow/brown when the heat is finally put into the plug like you want to see on the tip of the strap.
An autolite begins to show rainbow colors when the heat is correct and running right, which is even harder to see when the fueling is as rich as you are saying yours was.
At 15-16psi a BR7 is ok, personally above that I like a B8EFS, but you can skimp by with a BR7EFS. The range of control you can have over your timing with a cooler plug before pre-ignition or detonation is much greater than with a hotter plug. You still don't want to run the timing as far advanced as you can that doesn't knock like the classic quote I hear on here a lot, "Turn it up till it knocks then back it off one till it doesn't anymore".
When you are advancing the ignition spark, you are advancing the point when the spark fires as the piston is traveling upwards in it's compression stroke. The more advanced the ignition the further down in the bore the piston is while it is traveling back upwards from it's intake stroke. In an internal combustion piston driven engine the pistons move up and down with momentum and combustion event taking place inside the cylinder. When you begin to advance the timing so far that you begin to fight the pistons upward momentum from the last combustion event(explosion) that sent it downwards you are wasting energy. When you can use all of the pistons momentum from the previous combustion event THEN light the spark off that's PERFECT TIMING! Even if it doesn't show up as knock it shows up as wasted energy as excess heat on the plug. When you are making excess heat energy that cannot all be utilized the intake valve, exhaust valve, cylinder wall and spark plugs along with the piston have to absorb that heat and your rings also. Using the least amount of timing that uses all the previous combustion events momentum while still creating max power is perfect timing and it will show on the strap of the plug as being in the "range" you want to see. Again wasted energy will show on the plug and everywhere else so that's why you must use a colder plug when the pressures are going to be higher(more boost, more compression) because the heat will be higher! This is why stock rings can only take so much before failing.
Hope this makes sense to some.
The autolite plugs are a bit different to read than an NGK, but from what I can see that plug looks HOT! An autolite doesn't have the cadium plating on it that the NGK does so it doesn't get ashy color as the cadium begins to burn off and then turn light yellow/brown when the heat is finally put into the plug like you want to see on the tip of the strap.
An autolite begins to show rainbow colors when the heat is correct and running right, which is even harder to see when the fueling is as rich as you are saying yours was.
At 15-16psi a BR7 is ok, personally above that I like a B8EFS, but you can skimp by with a BR7EFS. The range of control you can have over your timing with a cooler plug before pre-ignition or detonation is much greater than with a hotter plug. You still don't want to run the timing as far advanced as you can that doesn't knock like the classic quote I hear on here a lot, "Turn it up till it knocks then back it off one till it doesn't anymore".
When you are advancing the ignition spark, you are advancing the point when the spark fires as the piston is traveling upwards in it's compression stroke. The more advanced the ignition the further down in the bore the piston is while it is traveling back upwards from it's intake stroke. In an internal combustion piston driven engine the pistons move up and down with momentum and combustion event taking place inside the cylinder. When you begin to advance the timing so far that you begin to fight the pistons upward momentum from the last combustion event(explosion) that sent it downwards you are wasting energy. When you can use all of the pistons momentum from the previous combustion event THEN light the spark off that's PERFECT TIMING! Even if it doesn't show up as knock it shows up as wasted energy as excess heat on the plug. When you are making excess heat energy that cannot all be utilized the intake valve, exhaust valve, cylinder wall and spark plugs along with the piston have to absorb that heat and your rings also. Using the least amount of timing that uses all the previous combustion events momentum while still creating max power is perfect timing and it will show on the strap of the plug as being in the "range" you want to see. Again wasted energy will show on the plug and everywhere else so that's why you must use a colder plug when the pressures are going to be higher(more boost, more compression) because the heat will be higher! This is why stock rings can only take so much before failing.
Hope this makes sense to some.
Last edited by Fbodyjunkie06; 07-10-2012 at 10:02 PM.