spark plugs.... Over thinking!

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Bextreme04

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yes, I should have clarified, a cylinder with more pressure, more stuff like oil or carbon etc...(such as on the plug itself) will require more to fire. so shortening the gap maybe then eases the needs on the coil and thus allows a spark to happen that may have been weaker all things equal otherwise with more gap?

im trying to word it as clearly as I can lol but I know when reading about waste spark, the cylinder not needing sparkas its on the exhaust stroke doesnt require as much voltage, but I also just learned apparently its also reversed polarity and im not sure now if that somehow affects it lol
What happens is that when all of those things are present you have more resistance to electrical flow. The coil only has so much voltage it can generate and if your total resistance from everything is more than the coil can overcome, you get NO spark. That's one of the reasons why forced induction engines and engines that run very high RPM use a smaller gap on their plugs. Its also one of the reasons that funny cars use dual magnetos and dual plugs(the other major reason is that nitromethane burns much slower than gasoline and you need to start combustion on both sides of the chamber to get complete combustion). There are a lot of variables and you just have to decide what your specific needs are. On my L29 I'm planning on running the double platinum or iridium plugs with .060" gap. It won't be turning high rpm and it will be CNP.
 

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yes, I should have clarified, a cylinder with more pressure, more stuff like oil or carbon etc...(such as on the plug itself) will require more to fire. so shortening the gap maybe then eases the needs on the coil and thus allows a spark to happen that may have been weaker all things equal otherwise with more gap?

im trying to word it as clearly as I can lol but I know when reading about waste spark, the cylinder not needing sparkas its on the exhaust stroke doesnt require as much voltage, but I also just learned apparently its also reversed polarity and im not sure now if that somehow affects it lol
I'll have what she's having! lol
 

SirRobyn0

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So ya'll know I've got the intake gaskets sitting on my desk at work right now. I'll bring them to the farm with me and I plan to change them on Friday. Basically I decided if I pull the intake and the gaskets are good, I won't be to happy about the time spent on it, but if I get a reman 350 and pull the intake to clean and swap onto it and find a blown gasket at that point I'm going to be super pisssed at myself for that. Plus obviously if this is the issue and fixes it I'll be happy about that.

I'll report back after completion.
 

Bextreme04

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So ya'll know I've got the intake gaskets sitting on my desk at work right now. I'll bring them to the farm with me and I plan to change them on Friday. Basically I decided if I pull the intake and the gaskets are good, I won't be to happy about the time spent on it, but if I get a reman 350 and pull the intake to clean and swap onto it and find a blown gasket at that point I'm going to be super pisssed at myself for that. Plus obviously if this is the issue and fixes it I'll be happy about that.

I'll report back after completion.
Yeah, it should only take about an hour to pull the intake manifold, clean it all up, and slap new gaskets in. Don't forget the thread sealant on the center bolts or you'll end up with oil on top of the manifold with some cylinder heads.
 

SirRobyn0

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Yeah, it should only take about an hour to pull the intake manifold, clean it all up, and slap new gaskets in. Don't forget the thread sealant on the center bolts or you'll end up with oil on top of the manifold with some cylinder heads.
Thanks, I think it'll probably take me a little longer than that as I'll need to dig the carbon out of the EGR passage while I've got it off. That and my body slows me down sometimes lol.
 

AuroraGirl

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What happens is that when all of those things are present you have more resistance to electrical flow. The coil only has so much voltage it can generate and if your total resistance from everything is more than the coil can overcome, you get NO spark. That's one of the reasons why forced induction engines and engines that run very high RPM use a smaller gap on their plugs. Its also one of the reasons that funny cars use dual magnetos and dual plugs(the other major reason is that nitromethane burns much slower than gasoline and you need to start combustion on both sides of the chamber to get complete combustion). There are a lot of variables and you just have to decide what your specific needs are. On my L29 I'm planning on running the double platinum or iridium plugs with .060" gap. It won't be turning high rpm and it will be CNP.
to my understandign, all big blocks run on a hot side of things yes? like temperature literally. if so, iridium is probably wise. double platinum gave GM issues with supercharged 3800s because it was causing pre ignition becuase the plug would be physically hot enough to ignite and the design of iridium used a small wire and transfered heat better.
i only mention because lowerish compression v6 cast iron and ngk (ac delco) iridum are good plugs and im pretty sure the late big blocks came with them in the very end(if not just platinum with smaller gap, barely)
 

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So ya'll know I've got the intake gaskets sitting on my desk at work right now. I'll bring them to the farm with me and I plan to change them on Friday. Basically I decided if I pull the intake and the gaskets are good, I won't be to happy about the time spent on it, but if I get a reman 350 and pull the intake to clean and swap onto it and find a blown gasket at that point I'm going to be super pisssed at myself for that. Plus obviously if this is the issue and fixes it I'll be happy about that.

I'll report back after completion.
Sounds like an emotional roller-coaster. @AuroraGirl might could share some cortisol? :console:
 

Bextreme04

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to my understandign, all big blocks run on a hot side of things yes? like temperature literally. if so, iridium is probably wise. double platinum gave GM issues with supercharged 3800s because it was causing pre ignition becuase the plug would be physically hot enough to ignite and the design of iridium used a small wire and transfered heat better.
i only mention because lowerish compression v6 cast iron and ngk (ac delco) iridum are good plugs and im pretty sure the late big blocks came with them in the very end(if not just platinum with smaller gap, barely)
You are confusing a few different concepts here and what people use "hot" to describe. The Big Blocks tend to run hotter(as in the block is harder to keep cool), due to the large amount of material in the casting and the way that the cooling system is designed. Basically there is a lot of mass in the block and not a lot of surface area for heat transfer to the coolant to happen(compared to some other engines).


With forced induction motors there are a lot of different factors. Generally you run less gap on a forced induction engine due to them having a tendency for the high cylinder pressures to "blow out" the spark. Iridium is generally the go-to for these motors as they have less resistance in the plug and less tendency to misfire due to cylinder pressure. You also generally will go with a "colder" plug with forced induction because the cylinder and exhaust temps are higher and you need the colder plug to transfer more heat away from the tip to prevent pre-ignition. That is a separate issue from the plug material though
 

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Yeah, it should only take about an hour to pull the intake manifold, clean it all up, and slap new gaskets in. Don't forget the thread sealant on the center bolts or you'll end up with oil on top of the manifold with some cylinder heads.
Lets break this statement down a bit. In MY experience it takes an hour to to explain to the wife why I NEED to work on the truck. Another 30 minutes to explain what a manifold is and 15 minutes to drive to Circle K to pick up a 12 pack. 30 minutes to find the tools I need, and 10 minutes to get some tunes blasting. Piss break #1=5 minutes. Stare at the engine for 15 minutes wondering if/why I'm really going to do this. Remove air cleaner, throttle cable and PCV hose=15 minutes. Piss break #2=5 minutes. 20 minutes to find that damn offset 9/16" wrench for the dizzy hold down bracket. Remove dizzy and plug wires. Piss break #3=5 minutes. 10 minutes to find a suitable container to drain coolant in. Remove lower radiator hose to drain coolant. 30 seconds to watch the entire coolant miss the container and drain all over the driveway while trying to keep the dog away. 5 minutes to wash driveway down with garden hose. Beer break # 3 (Two beers to deal with aggravation)=20 minutes. Remove intake bolts and top radiator hose. 10 minutes trying to find a lip for flat blade screwdriver to pry against that wont break the manifold flange. Remove manifold and watch in horror as all kind of debris falls into the intake runners and lifters. Piss break #4+ 10 minutes. Spend the next 1 FULL hour scraping and cleaning the gasket surface and heads of all gasket material while sniffing the acetone fumes. Another 20 minutes trying to get the threads clean of the thread sealant using a wire brush. Piss break #5=10 minutes.
Ok were at the halfway point!
10 minutes to endure the pain in your ribs as you lay across the fenders to apply the PERFECT bead of RTV on the rear intake flange. 7 minutes (although less painful) for the front. 1 minute to position the manifold gaskets. 3 minutes to get the courage up and steady the hands in order to place the manifold in place as graceful as a swan and in one perfect motion so as not to screw up those pretty RTV beads of silicone. 20 minutes to repeat the last three steps because you blew it! Piss break #6=5 minutes. Second time is a success! 5 minutes to slam another beer before finger tightening the intake bolts. 30 minutes to reinstall the dizzy, wires, hoses, coolant and throttle linkage. Piss break #7=5 minutes. 10 minutes to final tighten the intake bolts now that the RTV has cured. Replace air cleaner. 20 minutes to throw all the tools haphazardly into the tool box. 5 minutes to scrub hands with GOJO and garden hose. Hands and nails still disgusting. Piss break #7=5 minutes. 5 more minutes staring at engine trying to get the courage up to start it up. Nerves kick and and require another beer/Piss break #8 =10 minutes.
Crank it over until it tries to start=1 minute and 36 seconds. No start! Stare at engine in disbelief=10 minutes. Realize I didn't mark the dizzy when I pulled it. 2 more beers=20 minutes. Pull dizzy-find TDC-reinstall dizzy=42 minutes. Piss break #9=5 minutes. Stare at engine and say a prayer telling God you will change your ways if he allows it to start= 6 minutes.
Crank it over and she fires!!! Adjust timing and check for leaks=10 minutes. Tell God you were "just kidding"....have another beer=2 minutes.

So... @Bextreme04 telling him it "should only take about an hour" is not accurate or nice. People need to be told the truth and not have it sugarcoated. I'm not saying everyone has the same experience but I've had this same experience EVERY time I've done this at least three times.

So... @SirRobyn0 . Assuming you have a better way of doing things you should realistically plan on it requiring 6.46 hours of your time and at least 10-12 beers depending on your alcohol tolerance.

You all welcome.
 
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Bextreme04

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Lets break this statement down a bit. In MY experience it takes an hour to to explain to the wife why I NEED to work on the truck. Another 30 minutes to explain what a manifold is and 15 minutes to drive to Circle K to pick up a 12 pack. 30 minutes to find the tools I need, and 10 minutes to get some tunes blasting. Piss break #1=5 minutes. Stare at the engine for 15 minutes wondering if/why I'm really going to do this. Remove air cleaner, throttle cable and PCV hose=15 minutes. Piss break #2=5 minutes. 20 minutes to find that damn offset 9/16" wrench for the dizzy hold down bracket. Remove dizzy and plug wires. Piss break #3=5 minutes. 10 minutes to find a suitable container to drain coolant in. Remove lower radiator hose to drain coolant. 30 seconds to watch the entire coolant miss the container and drain all over the driveway while trying to keep the dog away. 5 minutes to wash driveway down with garden hose. Beer break # 3 (Two beers to deal with aggravation)=20 minutes. Remove intake bolts and top radiator hose. 10 minutes trying to find a lip for flat blade screwdriver to pry against that wont break the manifold flange. Remove manifold and watch in horror as all kind of debris falls into the intake runners and lifters. Piss break #4+ 10 minutes. Spend the next 1 FULL hour scraping and cleaning the gasket surface and heads of all gasket material while sniffing the acetone fumes. Another 20 minutes trying to get the threads clean of the thread sealant using a wire brush. Piss break #5=10 minutes.
Ok were at the halfway point!
10 minutes to endure the pain in your ribs as you lay across the fenders to apply the PERFECT bead of RTV on the rear intake flange. 7 minutes (although less painful) for the front. 1 minute to position the manifold gaskets. 3 minutes to get the courage up and steady the hands in order to place the manifold in place as graceful as a swan and in one perfect motion so as not to screw up those pretty RTV beads of silicone. 20 minutes to repeat the last three steps because you blew it! Piss break #6=5 minutes. Second time is a success! 5 minutes to slam another beer before finger tightening the intake bolts. 30 minutes to reinstall the dizzy, wires, hoses, coolant and throttle linkage. Piss break #7=5 minutes. 10 minutes to final tighten the intake bolts now that the RTV has cured. Replace air cleaner. 20 minutes to throw all the tools haphazardly into the tool box. 5 minutes to scrub hands with GOJO and garden hose. Hands and nails still disgusting. Piss break #7=5 minutes. 5 more minutes staring at engine trying to get the courage up to start it up. Nerves kick and and require another beer/Piss break #8 =10 minutes.
Crank it over until it tries to start=1 minute and 36 seconds. No start! Stare at engine in disbelief=10 minutes. Realize I didn't make the dizzy when I pulled it. 2 more beers=20 minutes. Pull dizzy-find TDC-reinstall dizzy=42 minutes. Piss break #9=5 minutes. Stare at engine and say a prayer telling God you will change your ways if he allows it to start= 6 minutes.
Crank it over and she fires!!! Adjust timing and check for leaks=10 minutes. Tell God you were "just kidding"....have another beer=2 minutes.

So... @Bextreme04 telling him it "should only take about an hour" is not accurate or nice. People need to be told the truth and not have it sugarcoated. I'm not saying everyone has the same experience but I've had this same experience EVERY time I've done this at least three times.

So... @SirRobyn0 . Assuming you have a better way of doing things you should realistically plan on it requiring 6.46 hours of your time and at least 10-12 beers depending on your alcohol tolerance.

You all welcome.
Jesus... this sounds like a day in the life of @AuroraGirl :happy175:
 

SirRobyn0

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Lets break this statement down a bit. In MY experience it takes an hour to to explain to the wife why I NEED to work on the truck. Another 30 minutes to explain what a manifold is and 15 minutes to drive to Circle K to pick up a 12 pack. 30 minutes to find the tools I need, and 10 minutes to get some tunes blasting. Piss break #1=5 minutes. Stare at the engine for 15 minutes wondering if/why I'm really going to do this. Remove air cleaner, throttle cable and PCV hose=15 minutes. Piss break #2=5 minutes. 20 minutes to find that damn offset 9/16" wrench for the dizzy hold down bracket. Remove dizzy and plug wires. Piss break #3=5 minutes. 10 minutes to find a suitable container to drain coolant in. Remove lower radiator hose to drain coolant. 30 seconds to watch the entire coolant miss the container and drain all over the driveway while trying to keep the dog away. 5 minutes to wash driveway down with garden hose. Beer break # 3 (Two beers to deal with aggravation)=20 minutes. Remove intake bolts and top radiator hose. 10 minutes trying to find a lip for flat blade screwdriver to pry against that wont break the manifold flange. Remove manifold and watch in horror as all kind of debris falls into the intake runners and lifters. Piss break #4+ 10 minutes. Spend the next 1 FULL hour scraping and cleaning the gasket surface and heads of all gasket material while sniffing the acetone fumes. Another 20 minutes trying to get the threads clean of the thread sealant using a wire brush. Piss break #5=10 minutes.
Ok were at the halfway point!
10 minutes to endure the pain in your ribs as you lay across the fenders to apply the PERFECT bead of RTV on the rear intake flange. 7 minutes (although less painful) for the front. 1 minute to position the manifold gaskets. 3 minutes to get the courage up and steady the hands in order to place the manifold in place as graceful as a swan and in one perfect motion so as not to screw up those pretty RTV beads of silicone. 20 minutes to repeat the last three steps because you blew it! Piss break #6=5 minutes. Second time is a success! 5 minutes to slam another beer before finger tightening the intake bolts. 30 minutes to reinstall the dizzy, wires, hoses, coolant and throttle linkage. Piss break #7=5 minutes. 10 minutes to final tighten the intake bolts now that the RTV has cured. Replace air cleaner. 20 minutes to throw all the tools haphazardly into the tool box. 5 minutes to scrub hands with GOJO and garden hose. Hands and nails still disgusting. Piss break #7=5 minutes. 5 more minutes staring at engine trying to get the courage up to start it up. Nerves kick and and require another beer/Piss break #8 =10 minutes.
Crank it over until it tries to start=1 minute and 36 seconds. No start! Stare at engine in disbelief=10 minutes. Realize I didn't make the dizzy when I pulled it. 2 more beers=20 minutes. Pull dizzy-find TDC-reinstall dizzy=42 minutes. Piss break #9=5 minutes. Stare at engine and say a prayer telling God you will change your ways if he allows it to start= 6 minutes.
Crank it over and she fires!!! Adjust timing and check for leaks=10 minutes. Tell God you were "just kidding"....have another beer=2 minutes.

So... @Bextreme04 telling him it "should only take about an hour" is not accurate or nice. People need to be told the truth and not have it sugarcoated. I'm not saying everyone has the same experience but I've had this same experience EVERY time I've done this at least three times.

So... @SirRobyn0 . Assuming you have a better way of doing things you should realistically plan on it requiring 6.46 hours of your time and at least 10-12 beers depending on your alcohol tolerance.

You all welcome.
LOL Sound like you work like me....

Honestly I know for me I can't get it done in an hour. That bit you wrote about ribs and fenders really hits home too. I generally do this kind of work in the morning on the farm so it's unlikely I'll be drinking during the job, but whiskey will come later.
 

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