Gary Lewis Posted July 3 Author Share Posted July 3 Gary, have you had time to install the cooler range spark plugs? I have and fired it up, but haven’t had a chance to drive it yet. We may take it for a spin this weekend. Link to comment Share on other sites More sharing options...
Rusty_S85 Posted July 5 Share Posted July 5 You'll see a parallel post entitled Exhaust Noise Questions, which was caused by noise in the headers I've recently noticed. And that prompted me to pull the plugs today in an effort to rule out a fouled plug or an overly-rich mix. But as you'll see, the plugs say the mix is not rich. I'll show two pics of the plugs below, but my question is what to go back with. These are NGK UR5's, but I recently bought UR4's to replace these, and I just discovered that these are one notch hotter than the 5's. So I'm thinking that I don't want to go hotter give the state of these plugs - would you agree? The plugs on the left have been turned to show the color, which isn't all that much. And on the right the color is turned away from the camera. But the white is about as white as the new plugs I bought. Comments, please! https://forum.garysgaragemahal.com/file/n155817/NGK_UR5_-_Dark_Side.jpghttps://forum.garysgaragemahal.com/file/n155817/NGK_UR5_-_Light_Side.jpg Late reply just saw this, but what I am seeing is the plugs you have in now are too hot and you need a colder plug not a hotter plug. You have nice colorization on the electrode strap indicating you have good heat, but the clean white porcelain is showing your plug is running too hot and is burning everything off preventing a nice fuel ring around the base of the porcelain. The black specs on cylinder number one is a sign of detonation, carbon is being blown off the piston and is sticking to the porcelain. Cylinder three has some slight speckling on the porcelain indicating it has some detonation as well. Another thing is your timing mark on the electrode strap is not too bad, depending on the source they want that timing mark on the electrode strap to be from between the ninety-degree curve and the fire ring where it is welded at. Some like cylinder seven I feel is a bit too close to the weld while cylinder eight I feel is about ideal close to the ninety-degree curve. I wouldn't mess with the timing however, I would try running one plug colder temp wise try and get some color into the porcelain, that should knock down on your slight detonation issue, it also has a very good chance at moving your timing mark on the electrode strap closer to the ninety-degree curve. Link to comment Share on other sites More sharing options...
Gary Lewis Posted July 5 Author Share Posted July 5 You'll see a parallel post entitled Exhaust Noise Questions, which was caused by noise in the headers I've recently noticed. And that prompted me to pull the plugs today in an effort to rule out a fouled plug or an overly-rich mix. But as you'll see, the plugs say the mix is not rich. I'll show two pics of the plugs below, but my question is what to go back with. These are NGK UR5's, but I recently bought UR4's to replace these, and I just discovered that these are one notch hotter than the 5's. So I'm thinking that I don't want to go hotter give the state of these plugs - would you agree? The plugs on the left have been turned to show the color, which isn't all that much. And on the right the color is turned away from the camera. But the white is about as white as the new plugs I bought. Comments, please! https://forum.garysgaragemahal.com/file/n155817/NGK_UR5_-_Dark_Side.jpghttps://forum.garysgaragemahal.com/file/n155817/NGK_UR5_-_Light_Side.jpg Late reply just saw this, but what I am seeing is the plugs you have in now are too hot and you need a colder plug not a hotter plug. You have nice colorization on the electrode strap indicating you have good heat, but the clean white porcelain is showing your plug is running too hot and is burning everything off preventing a nice fuel ring around the base of the porcelain. The black specs on cylinder number one is a sign of detonation, carbon is being blown off the piston and is sticking to the porcelain. Cylinder three has some slight speckling on the porcelain indicating it has some detonation as well. Another thing is your timing mark on the electrode strap is not too bad, depending on the source they want that timing mark on the electrode strap to be from between the ninety-degree curve and the fire ring where it is welded at. Some like cylinder seven I feel is a bit too close to the weld while cylinder eight I feel is about ideal close to the ninety-degree curve. I wouldn't mess with the timing however, I would try running one plug colder temp wise try and get some color into the porcelain, that should knock down on your slight detonation issue, it also has a very good chance at moving your timing mark on the electrode strap closer to the ninety-degree curve. Thanks. I did go one notch colder on the plugs and we took a ~200 mile trip today with no problems. I'll pull the #1 plug one of these days and post a closeup of it beside the previous #1 plug. As for detonation, I think I can tell a little bit of difference. Before it rattled a bit when I got it below 1000 RPM, but today it didn't seem to do that. However that is quite subjective so I'll drive it more and see if that observation holds. Link to comment Share on other sites More sharing options...
Rusty_S85 Posted July 5 Share Posted July 5 Thanks. I did go one notch colder on the plugs and we took a ~200 mile trip today with no problems. I'll pull the #1 plug one of these days and post a closeup of it beside the previous #1 plug. As for detonation, I think I can tell a little bit of difference. Before it rattled a bit when I got it below 1000 RPM, but today it didn't seem to do that. However that is quite subjective so I'll drive it more and see if that observation holds. You should be good on the detonation, when you pull the plugs out now you should have a tan color porcelain which means you are not too hot and not too cold. I suspect what was happening is your electrode was getting hot enough on some cylinders to cause a slight detonation. You didnt have what appeared to be silver pyramids so you weren't knocking metal off your pistons, you were detonating just enough to rattle some carbon loose. Heres an old diagram I got about timing indicator mark on the electrode strap. Its one of those things that I am kind of dreading to do for my build, considering the proper way to do a plug read is to do a hard full throttle pass then kill the ignition system then pull the plugs. No way for me to do that unless I do it on the side of the road away from home. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted July 5 Share Posted July 5 Thanks. I did go one notch colder on the plugs and we took a ~200 mile trip today with no problems. I'll pull the #1 plug one of these days and post a closeup of it beside the previous #1 plug. As for detonation, I think I can tell a little bit of difference. Before it rattled a bit when I got it below 1000 RPM, but today it didn't seem to do that. However that is quite subjective so I'll drive it more and see if that observation holds. You should be good on the detonation, when you pull the plugs out now you should have a tan color porcelain which means you are not too hot and not too cold. I suspect what was happening is your electrode was getting hot enough on some cylinders to cause a slight detonation. You didnt have what appeared to be silver pyramids so you weren't knocking metal off your pistons, you were detonating just enough to rattle some carbon loose. Heres an old diagram I got about timing indicator mark on the electrode strap. Its one of those things that I am kind of dreading to do for my build, considering the proper way to do a plug read is to do a hard full throttle pass then kill the ignition system then pull the plugs. No way for me to do that unless I do it on the side of the road away from home. Plug chops are a pain now that we have knock sensors and AFR meters.. God I used to loathe the time spent for hundredths, and costly teardowns when you missed, or the weather bit you in the butt. Top fuel guys have the almost unlimited budget to be on the ragged edge. I'd rather be safe than sorry. Link to comment Share on other sites More sharing options...
Rusty_S85 Posted July 5 Share Posted July 5 Plug chops are a pain now that we have knock sensors and AFR meters.. God I used to loathe the time spent for hundredths, and costly teardowns when you missed, or the weather bit you in the butt. Top fuel guys have the almost unlimited budget to be on the ragged edge. I'd rather be safe than sorry. Yep they are a pain, for me I will have to do it cause my engine is all new and nothing from the factory so I have to figure out what plugs mine need. My starting point is what AFR recommended for my heads and they state they are a pretty commonly used plug with my head so I should be fine. I still want to do a chop to make sure everything is good. I dont have knock sensors nor computer controlled timing but I do have an aftermarket EFI system to take over my fuel so I am not too concerned about AFR, I am more concerned about my plug heat range and my ignition advance as well as if I am detonating or not since my timing is going to be a bit on the edge of what all sources state I should be running for fast burn cylinder heads. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted July 5 Share Posted July 5 Plug chops are a pain now that we have knock sensors and AFR meters.. God I used to loathe the time spent for hundredths, and costly teardowns when you missed, or the weather bit you in the butt. Top fuel guys have the almost unlimited budget to be on the ragged edge. I'd rather be safe than sorry. Yep they are a pain, for me I will have to do it cause my engine is all new and nothing from the factory so I have to figure out what plugs mine need. My starting point is what AFR recommended for my heads and they state they are a pretty commonly used plug with my head so I should be fine. I still want to do a chop to make sure everything is good. I dont have knock sensors nor computer controlled timing but I do have an aftermarket EFI system to take over my fuel so I am not too concerned about AFR, I am more concerned about my plug heat range and my ignition advance as well as if I am detonating or not since my timing is going to be a bit on the edge of what all sources state I should be running for fast burn cylinder heads. Aluminum heads really change things. They can sink so much heat you may find you need to go two steps hotter than with CI and the same build, but I suppose you'll find out. Always good to start with manufacturers recommendations! Link to comment Share on other sites More sharing options...
Rusty_S85 Posted July 5 Share Posted July 5 Aluminum heads really change things. They can sink so much heat you may find you need to go two steps hotter than with CI and the same build, but I suppose you'll find out. Always good to start with manufacturers recommendations! Yes, aluminum really pulls heat away, plug AFR recommended as a starting point was Autolite 3924 copper plugs. From the Autolite tech sheets I found online there is no clear-cut way to rank Autolite plugs to compare them, but my plug is the 392 family, it is a resistor plug and it is a 4 on the heat range. This family consists of plugs 3922, 3923, 3924, and 3926, so my 3924 plugs are on the hot side of the family range and even summit states for mild small block aluminum head builds the 3924 would be used in many of these applications. I just need to make sure because in my case once I move 90% of my driving will be at 65 - 75 mph on the highway for hours on end turning between 2,400 and 3,000 rpm. So, I might need to go with a 3926 if the aluminum heads, 7 bladed flex fan, and aluminum 2 core radiator draws too much heat out of the plug. On the flip side it might be too hot and I need to go down to a 3923 plug. One thing I found interesting is the 3924 plug translates to a RC12YC champion or a FR5 NGK plug. What caught my eye was the 12Y for champion, my old Fairlane took 14Y Champions when new which sadly is no longer produced since I wanted to keep with champions. Just like these 3924 plugs I tried to find a Motorcraft cross over I prefer Motorcraft plugs over autolites but there is no cross over. Yes, it is good to start with what the manufacturer suggests, they built whatever you are using, and they know a good starting point if not what to use regardless. Link to comment Share on other sites More sharing options...
ArdWrknTrk Posted July 5 Share Posted July 5 Aluminum heads really change things. They can sink so much heat you may find you need to go two steps hotter than with CI and the same build, but I suppose you'll find out. Always good to start with manufacturers recommendations! Yes, aluminum really pulls heat away, plug AFR recommended as a starting point was Autolite 3924 copper plugs. From the Autolite tech sheets I found online there is no clear-cut way to rank Autolite plugs to compare them, but my plug is the 392 family, it is a resistor plug and it is a 4 on the heat range. This family consists of plugs 3922, 3923, 3924, and 3926, so my 3924 plugs are on the hot side of the family range and even summit states for mild small block aluminum head builds the 3924 would be used in many of these applications. I just need to make sure because in my case once I move 90% of my driving will be at 65 - 75 mph on the highway for hours on end turning between 2,400 and 3,000 rpm. So, I might need to go with a 3926 if the aluminum heads, 7 bladed flex fan, and aluminum 2 core radiator draws too much heat out of the plug. On the flip side it might be too hot and I need to go down to a 3923 plug. One thing I found interesting is the 3924 plug translates to a RC12YC champion or a FR5 NGK plug. What caught my eye was the 12Y for champion, my old Fairlane took 14Y Champions when new which sadly is no longer produced since I wanted to keep with champions. Just like these 3924 plugs I tried to find a Motorcraft cross over I prefer Motorcraft plugs over autolites but there is no cross over. Yes, it is good to start with what the manufacturer suggests, they built whatever you are using, and they know a good starting point if not what to use regardless. I've had problems out of the box with Autolite. Ceramic not crimped into body, cracked insulators, twisted ground or flat against the center conductor. And I can never seem to get 8 that are correctly gapped. I've been using NGK V-power since the mid '70's in dirt, and then street bikes. Now the bikes take crazy $25 plugs but I keep using V-power in my truck. I use UR4, and am surprised that Gary needed to go colder with his far more efficient F3TE heads. Some people don't understand how they change the heat.range.... The ceramic cone in the plug goes deeper, making for a longer path to the head, where the heat is pulled away. Therefore the tip stays hotter. Like you said, if you read the carbon ring you can tell where it stays hot enough to burn away. Link to comment Share on other sites More sharing options...
Gary Lewis Posted July 5 Author Share Posted July 5 Thanks. I did go one notch colder on the plugs and we took a ~200 mile trip today with no problems. I'll pull the #1 plug one of these days and post a closeup of it beside the previous #1 plug. As for detonation, I think I can tell a little bit of difference. Before it rattled a bit when I got it below 1000 RPM, but today it didn't seem to do that. However that is quite subjective so I'll drive it more and see if that observation holds. You should be good on the detonation, when you pull the plugs out now you should have a tan color porcelain which means you are not too hot and not too cold. I suspect what was happening is your electrode was getting hot enough on some cylinders to cause a slight detonation. You didnt have what appeared to be silver pyramids so you weren't knocking metal off your pistons, you were detonating just enough to rattle some carbon loose. Heres an old diagram I got about timing indicator mark on the electrode strap. Its one of those things that I am kind of dreading to do for my build, considering the proper way to do a plug read is to do a hard full throttle pass then kill the ignition system then pull the plugs. No way for me to do that unless I do it on the side of the road away from home. Rusty - Your plug diagram matches what I've read, and both say the timing is about right - for part throttle usage. I've not done any full throttle runs in a long time, and certainly haven't stopped on the side of the road to read the plugs. And I agree that the UR5's may have been causing pinging or detonation at low RPM. I have a corner in the neighborhood that is fairly tight and the engine would rattle if I took it in 3rd and gave it any throttle at all. That was down just below 1000 RPM. But yesterday I tried it after we'd been on the highway for 90 minutes and it didn't rattle. Maybe tomorrow I can pull #1 and see what it looks like. Link to comment Share on other sites More sharing options...
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