Except some of the best roast masters have moved on.
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- Thread starter Heaten m90
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Except some of the best roast masters have moved on.
Heaten m90
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Good info below
The best indication of detonation is the pinging sound that cars, particularly old models, make at low speeds and under load. It is very difficult to hear the sound in well insulated luxury interiors of today’s cars. An unmuffled engine running straight pipes or a propeller turning can easily mask the characteristic ping. The point is that you honestly don’t know that detonation is going on. In some cases, the engine may smoke but not as a rule. Broken piston ring lands are the most typical result of detonation but are usually not spotted. If the engine has detonated visual signs like broken spark plug porcelains or broken ground electrodes are dead giveaways and call for further examination or engine disassembly.
It is also very difficult to sense detonation while an engine is running in an remote and insulated dyno test cell. One technique seems almost elementary but, believe it or not, it is employed in some of the highest priced dyno cells in the world. We refer to it as the “Tin Ear”. You might think of it as a simple stethoscope applied to the engine block. We run a ordinary rubber hose from the dyno operator area next to the engine. To amplify the engine sounds we just stick the end of the hose through the bottom of a Styrofoam cup and listen in! It is common for ride test engineers to use this method on development cars particularly if there is a suspicion out on the road borderline detonation is occurring. Try it on your engine; you will be amazed at how well you can hear the different engine noises.
The other technique is a little more subtle but usable if attention is paid to EGT (Exhaust Gas Temperature). Detonation will actually cause EGTs to drop. This behavior has fooled a lot of people because they will watch the EGT and think that it is in a low enough range to be safe, the only reason it is low is because the engine is detonating.
The only way you know what is actually happening is to be very familiar with your specific engine EGT readings as calibrations and probe locations vary. If, for example, you normally run 1500 degrees at a given MAP setting and you suddenly see 1125 after picking up a fresh load of fuel you should be alert to possible or incipient detonation. Any drop from normal EGT should be reason for concern. Using the “Tin Ear” during the early test stage and watching the EGT very carefully, other than just plain listening with your ear without any augmentation, is the only way to identify detonation. The good thing is, most engines will live with a fairly high level of detonation for some period of time. It is not an instantaneous type failure.
The best indication of detonation is the pinging sound that cars, particularly old models, make at low speeds and under load. It is very difficult to hear the sound in well insulated luxury interiors of today’s cars. An unmuffled engine running straight pipes or a propeller turning can easily mask the characteristic ping. The point is that you honestly don’t know that detonation is going on. In some cases, the engine may smoke but not as a rule. Broken piston ring lands are the most typical result of detonation but are usually not spotted. If the engine has detonated visual signs like broken spark plug porcelains or broken ground electrodes are dead giveaways and call for further examination or engine disassembly.
It is also very difficult to sense detonation while an engine is running in an remote and insulated dyno test cell. One technique seems almost elementary but, believe it or not, it is employed in some of the highest priced dyno cells in the world. We refer to it as the “Tin Ear”. You might think of it as a simple stethoscope applied to the engine block. We run a ordinary rubber hose from the dyno operator area next to the engine. To amplify the engine sounds we just stick the end of the hose through the bottom of a Styrofoam cup and listen in! It is common for ride test engineers to use this method on development cars particularly if there is a suspicion out on the road borderline detonation is occurring. Try it on your engine; you will be amazed at how well you can hear the different engine noises.
The other technique is a little more subtle but usable if attention is paid to EGT (Exhaust Gas Temperature). Detonation will actually cause EGTs to drop. This behavior has fooled a lot of people because they will watch the EGT and think that it is in a low enough range to be safe, the only reason it is low is because the engine is detonating.
The only way you know what is actually happening is to be very familiar with your specific engine EGT readings as calibrations and probe locations vary. If, for example, you normally run 1500 degrees at a given MAP setting and you suddenly see 1125 after picking up a fresh load of fuel you should be alert to possible or incipient detonation. Any drop from normal EGT should be reason for concern. Using the “Tin Ear” during the early test stage and watching the EGT very carefully, other than just plain listening with your ear without any augmentation, is the only way to identify detonation. The good thing is, most engines will live with a fairly high level of detonation for some period of time. It is not an instantaneous type failure.
Wes06
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Well in that case. There were methods to hear detonation, and by being very familiar with the setup.
With that setup there should have been monitors for the egts and other such readings.
So either they weren't there, or they were ignored. Still failure of operators it seems
With that setup there should have been monitors for the egts and other such readings.
So either they weren't there, or they were ignored. Still failure of operators it seems
Heaten m90
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Yes, and it would appear that way..... I've worked on engines for many years, mainly large bore diesel. Electrical engineering is my strong suit but i work in the electrical power generation feild and the typical prime mover is an internal combustion engine which im responsible for repairing and maintaining(along with all the other systems). Im in no way an expert, im still learning and will be the rest of my life. However i do retain everything and always try to better myself. although most the members here are savage ass holes they do have alot of knowledge to share lol
RocketcarX
95% of my weight is fuel
I dub thee "Shep", you like dubstep?
dark steed
Resident noob
A dumber sentence in relation to modded engines was never written.
A stock engine that gets crappy gas will probably survive a tank here or there. Not sure that would be valid with the ecoboost mustang though.
RocketcarX
95% of my weight is fuel
This is the "oh fuck" moment for me.
You owe the man an engine, sir.
What shitty head are you running that is ok with 42* of timing? Good lord, you started at max timing and went for broke which lower octane fuel...what could go wrong?
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Heaten m90
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I gave my buddy all the 116 i had left when we were loading up my engine and heading there, he said there was a fuel charge on the quote for testing but we brought the extra just in case. Honestly when i saw the dyno operator pouring the 110 in after my fuel ran out i was wondering, i even expressed concern asking if a system like this could incorporate some sort of knock sensor. He said its possible but diffcult due to resonation issues. I just assumed operator/builder knew the octane/spark limits and had ordered fuel accordingly. brodix heads, everything was top of the line in this motor well over 20K.
RocketcarX
95% of my weight is fuel
Post a pic of the pistons
Maybe I'm confused, were you doing the tuning or the dyno shop?
So most of these modern BBC heads want a max of 32* timing, def don't start at 35*. You start at 26 or so and run the power in 2* at a time. You should have known better than to change to a fuel you don't race on, what good is the "tune" at that point?
Detonation will take out an engine like that in one dyno pull, there is no room for "pushing it", or sticking to the old ways doing shit like running the timing in until "she pings". In an engine that high strung it all happens way faster, and with much more force.
Maybe I'm confused, were you doing the tuning or the dyno shop?
So most of these modern BBC heads want a max of 32* timing, def don't start at 35*. You start at 26 or so and run the power in 2* at a time. You should have known better than to change to a fuel you don't race on, what good is the "tune" at that point?
Detonation will take out an engine like that in one dyno pull, there is no room for "pushing it", or sticking to the old ways doing shit like running the timing in until "she pings". In an engine that high strung it all happens way faster, and with much more force.
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Heaten m90
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The tuning/test cell was itemized and payed for in the quote, so they were running the show. My buddy has been tuning that car at the track for years though. I was just asked to troubleshoot the ignition system and wiring. We were still on their shop 1150 dominator when it blew the next run we were going to switch to his carb and start making high RPM pulls. Ill post some pics
Heaten m90
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Wes06
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no pics of the glory hole on the block?
what a let down.....lol
what a let down.....lol
RocketcarX
95% of my weight is fuel
Lets' see the pistons already
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