Up in Flames... Fire Bad!
03-27-2007, 08:31 PM
#81
Originally Posted by jester1
So it wasnt a 285 hit. It was more, have you figured out what size shot it was? That was a stock bottom right down to the rod bolts? Have you checked for bent rods? Im supprised that those hyper pistons took that kind of abuse before it let go, Im impressed to say the least. Its really unfortunate that one persons catastrophy is anothers bible of what not to do.
The kit is rated at 285 rwhp what would that equate to fwhp?
The kit is rated at 285 rwhp what would that equate to fwhp?
Robert
03-27-2007, 08:40 PM
#82
Originally Posted by lxh89
Out of curiosity, besides running a rather hot plug (a TR6), were you running a fuel with at least a 99 Octane Mon (Ie. VP 109 unleaded, Sunoco GT Plus 104 unleaded)?
To me it looks like the plugs caused pre-ignition due to the immense heat on the plugs. You said the car went flat? If the spark plugs were glowing red, as soon as the A/F mix got into the combustion chamber and piston was heading up to compress, it likely ignited the mixture partially, very early on the compression stroke. We are talking up to 180 degrees BTDC! Also, with pre-ignition you will not hear ANYTHING. No marbles in a coffee can, no ping, nothing, just the motor will nose over flat like theres no power or little power.
Now, those cylinders experiencing this effect would be subjected to immense heat which is indicative on that melted piston. With hypereutectic pistons, they usually shatter under detonation. That piston was melted due to heat! The spark plug electrodes also show signs of melting due to heat.
I vote the spark plugs not the lack of fuel nor the size of the nitrous shot contributed to the untimely demise of this engine.
Tony
To me it looks like the plugs caused pre-ignition due to the immense heat on the plugs. You said the car went flat? If the spark plugs were glowing red, as soon as the A/F mix got into the combustion chamber and piston was heading up to compress, it likely ignited the mixture partially, very early on the compression stroke. We are talking up to 180 degrees BTDC! Also, with pre-ignition you will not hear ANYTHING. No marbles in a coffee can, no ping, nothing, just the motor will nose over flat like theres no power or little power.
Now, those cylinders experiencing this effect would be subjected to immense heat which is indicative on that melted piston. With hypereutectic pistons, they usually shatter under detonation. That piston was melted due to heat! The spark plug electrodes also show signs of melting due to heat.
I vote the spark plugs not the lack of fuel nor the size of the nitrous shot contributed to the untimely demise of this engine.
Tony
I think the preingnition you propose can lead directly to detonation.
Robert
03-27-2007, 09:13 PM
#83
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Originally Posted by Robert56
Not disagreeing, as I have not formed a total opinion yet; but I think the ring land snapping left a nice place for hot spot to form. Once this happens it's like a cutting torch effect and thus the melt down. Preignition/detontation either or both were certainly at play. Once you have a hot spot (plugs and/or piston edge) all bets are off.
I think the preingnition you propose can lead directly to detonation.
Robert
I think the preingnition you propose can lead directly to detonation.
Robert
Many people confuse pre-ignition and detonation, but they are entirely different processes. Detonation is purely related to abnormal combustion after the spark plug has fired whereby flame front travel is disorderly and erratic. You end up with outer layers of unburnt A/F igniting spontaneously before the original flame front ever meets it to continue orderly combustion.
Contrary to popular belief, detonation isn't the immediate killer of engines. In many cases, detonation can continue for a prolonged time with little noticeable damage.
With pre-ignition, we are talking about ignition before the spark plug is ever fired. This is the reason why a motor which is pre-igniting may result in power loss and no audible pinging. The more degrees away from top-dead-center the piston is when the pre-ignition occurs, the less opportunity for detonation, and the more heat generated.
In a case where pre-ignition happens to ignitethe mixture 30 deg before-top-dead-center then you can get detonation because now we have combustion started right before the compression stroke and before the spark plug fires creating another flame front.
Hope that explains things a little better.
Tony
Last edited by lxh89; 03-27-2007 at 11:29 PM.
03-27-2007, 11:12 PM
#84
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Originally Posted by Robert56
Not disagreeing, as I have not formed a total opinion yet; but I think the ring land snapping left a nice place for hot spot to form. Once this happens it's like a cutting torch effect and thus the melt down. Preignition/detontation either or both were certainly at play. Once you have a hot spot (plugs and/or piston edge) all bets are off.
I think the preingnition you propose can lead directly to detonation.
Robert
I think the preingnition you propose can lead directly to detonation.
Robert
You had one ring land snap but multiple burnt plugs. So I dont thing the ring snap came first.
I like LXH89's theory. Although I do belive that if you had enough octane that TR6 would have been ok. Not the best choice...but ok.
03-28-2007, 01:15 AM
#85
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An dual EGT setup would be so beneficial in a big shot setup like this.....
With the kind of temps you saw in the cylinders, you MAY
have been able to see the problem soon enough.
With the kind of temps you saw in the cylinders, you MAY
have been able to see the problem soon enough.
03-31-2007, 01:13 PM
#86
Found out the block is not repairable/usable. Doing this on the cheap is not working out. Rec on a good short block for a reasonable price, using my existing heads and other goodies? I know LME has a good deal on a 408 iron shortblock...
Robert
Robert
03-31-2007, 01:56 PM
#88
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Robert...be sure to check the heads. Many times when the plugs are that bad that exhaust valve or seat may have some sealing issues. However if you go with a 408 im sure you wont use stock heads. Just and FYI.
PS..sucks about the block. But now you can go BIG!
PS..sucks about the block. But now you can go BIG!
03-31-2007, 02:07 PM
#89
geremeezy, the block was scoured and at first we thought it could be honed out, but damage is to bad.
Al, yea the heads are apart and they are fine, just clean up the faces/seats and new springs and we are good to go. i am trying to do this cheap, so the 408 and new heads, well...
Robert
Al, yea the heads are apart and they are fine, just clean up the faces/seats and new springs and we are good to go. i am trying to do this cheap, so the 408 and new heads, well...
Robert
03-31-2007, 03:46 PM
#91
Originally Posted by 383LQ4SS
Consider a 402 LS2? Those are cheap, have almost the same cubes and dont add 100 lbs with an iron block.
Robert
04-01-2007, 10:51 PM
#94
Pin Pointed problem(s) Well Ibelieve I found the issue(s). It was self inflicted by my tuner, which is me. 
My logs were still on my laptop, so in the linked thread I show what I found.
Dyno Logs Reveiled
Robert
My logs were still on my laptop, so in the linked thread I show what I found.
Dyno Logs Reveiled
Robert
04-03-2007, 12:20 PM
#96
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Originally Posted by lxh89
Out of curiosity, besides running a rather hot plug (a TR6), were you running a fuel with at least a 99 Octane Mon (Ie. VP 109 unleaded, Sunoco GT Plus 104 unleaded)?
To me it looks like the plugs caused pre-ignition due to the immense heat on the plugs. You said the car went flat? If the spark plugs were glowing red, as soon as the A/F mix got into the combustion chamber and piston was heading up to compress, it likely ignited the mixture partially, very early on the compression stroke. We are talking up to 180 degrees BTDC! Also, with pre-ignition you will not hear ANYTHING. No marbles in a coffee can, no ping, nothing, just the motor will nose over flat like theres no power or little power.
Now, those cylinders experiencing this effect would be subjected to immense heat which is indicative on that melted piston. With hypereutectic pistons, they usually shatter under detonation. That piston was melted due to heat! The spark plug electrodes also show signs of melting due to heat.
I vote the spark plugs not the lack of fuel nor the size of the nitrous shot contributed to the untimely demise of this engine.
Tony
To me it looks like the plugs caused pre-ignition due to the immense heat on the plugs. You said the car went flat? If the spark plugs were glowing red, as soon as the A/F mix got into the combustion chamber and piston was heading up to compress, it likely ignited the mixture partially, very early on the compression stroke. We are talking up to 180 degrees BTDC! Also, with pre-ignition you will not hear ANYTHING. No marbles in a coffee can, no ping, nothing, just the motor will nose over flat like theres no power or little power.
Now, those cylinders experiencing this effect would be subjected to immense heat which is indicative on that melted piston. With hypereutectic pistons, they usually shatter under detonation. That piston was melted due to heat! The spark plug electrodes also show signs of melting due to heat.
I vote the spark plugs not the lack of fuel nor the size of the nitrous shot contributed to the untimely demise of this engine.
Tony
04-03-2007, 08:33 PM
#99
Originally Posted by JL ws-6
Give eastside a call before you build anything, get a price from them. They've built a ton of nitrous motors... I am sure they can build you one for as much as you want to push to it.
Robert
