I've been watching car videos for years, and they'd talk about reading plugs, but never broke it down. I learned more in 5 minutes with this video than 5 plus years of watching car youtubers. Bravo!
The Steve Tech videos are accurate and very informative. Thank you Steve Morris for providing everyone in the automotive world with your wisdom, free of charge.
no truer words were ever spoken. I was taught this back in the 60s by a tune up guru. your exact explanation . All "tune them alls " tune via a lap top and dont wanna get there hands dirty. another good tool is a gas analizer, Co and HC under load tell a lot but most guys cant afford one and they cost a mint these days . I still have my old sun 111 5 and tuned 1000s of edelbrocks and hollys with it and reading plugs . you da man steve. Gawd I wish I were younger,
Gas analyzers have a problem. They measure only what is left over at the end when what you really need is the condition during actual combustion at +/- TDC where the power is actually made. The fuel continues to react even late in the stroke and in the exhaust ports even though it does nothing for power at that point. So they can easily give you a false impression. What you'd really like is a sample taken from the chamber at about 30 deg ATC.
Steve, I think you should do a video on "when to check your plugs". For example, I would make a pass and right at the 1/4 beams, pop the trans in neutral and shut the engine off. Tow back to the pits, let the engine cool and then pull plugs to take a reading. Those (and more details) would really be helpful to your audience (in my opinion) Thanks for all the GREAT videos!
Doesn’t have to be to the 1/4. Can just be a good 1 to 2 gear pull. Pull off to the side of the road shut the car off and pull one of the plug. It’s a tedious process. But I did it. And I noticed a good difference in how my car reacts. Steve is smart af
you know we take it for granted all the time like you said the data but then actually look at the physical spark plug is where you get the most accurate result thank you Steve
Excellent video, man. Love it. I used to watch the ol’ timers at the drag strip read there plugs with a jewelers eye loop. Now I know what they were reading.
Just want to say thanks for putting this info out there this is a great video! I applied this process to the 364ci SBC I built and put in my nissan240sx Ended up taking 2 jets from the primary and 6 from the secondary on a proform 750dp. tuned for the leanest hottest cylinder got it perfect as I could and the old butt Dyno says it picked up 20-30hp everywhere but next trip to the strip will tell. Thanks again bud keep up the great work. I have known about your engines for years but think it's the greatest thing to actually learn something straight from one of the best have a good one brother!
Wow thanks. About half of what family members have told about looking plugs has turned out to be true. Now I’m going to go look at what top fuel plugs look like after a run just to see most extreme conditions.
Your vids are awesome. You're my new engine Dad. Thanks for the knowledge man this is solid gold. Watched almost all of the tech vids twice now and I plan on watchin' 'em again and again
Dang Steve, In my 35+ years of tinkering with muscle cars off and on, I've never been told about cutting a plug open to look at the porcelain down inside. Just traded my 2012 Camaro for a 71 with a 383 and carb, so I'm definitely headed to a box store to get a 5/8" deep hole saw. Thanks!
@@stevemorrisracing Would this plug reading process apply the same for a turbo motor? For nitrous, does the plug read differently between NA and the hit? Which one do you tune by? Great video btw
Hey Steve, appreciate your contribution to teaching us with info we would never find on the internet for free. I do have a couple of questions. Just curious what would be a good exh temp for an N.A, SBC 377 cuin drag motor with a set of hilborn mechanical fuel injectors on meth. The motor seems to want to nose over on the big end would that be the motor going lean. I have not applied what you have in this video but will the next time to the track. the fuel system has a high-speed bypass we can adjust by increasing or decreasing the pressure it pops off along with a jet we can change. The motor does not mis or pop when it noses over. what would be a good exh temp we are seeing temps in the 1100 to 1130 range? what is the difference in reading a gas vs. alcohol motor spark plug ? Thanks for your help in advance.
Thread coloring doesn’t really matter. In fact it might add power. It’s using the threads further into the combustion chamber reducing the volume inside. I have about 2 rings on inside the combustion. Just like the this spark plug in the video
much respect, but no mention of spark plug heats because that is a lot to do with how much of that strap stays hot and burns that crust off the strap maybe he assumes you've already selected the correct heat of the spark plug but in my eyes it's one of the things you should read and adjust. again much respect as I've learned so much from you videos
Yup this is right on. Back in the day this is all we had. Every body ran iron heads so pulling a plug out was no big. Be careful doing that on a hot alloy head.
I used to work as a tech for a tuner that would burn the straps of plugs like they owed him money. Over the years I have learned that really good tuners are hard to find.
Nice detail on that. Don't know if I will ever get to the point if cutting into a spark plug, but definitely will be looking a bit harder at them. Who over ....say, 45 years old, does not read a plug?
What about on a street engine? I get that with a drag car you want to make a WOT pull then check the plug. But that’s not how street engines are driven. How would you recommend this be performed with a street engine? Drive normally, with a couple WOT pulls, then check? Thanks! Loved the video!
Great Video on the plugs!!! How does the heat range effect the function, and how can you read if it´s a too hot or cold plug? Thank you again! :) Br Jonas in Sweden / BBF 429 cui / Hyd rollercam, alu heads, Edelbrock pro flo 4 , in a 1958 Edsel :)
Steve, how does the heat range affect this? I would think for the same AFR, you could have different heights of the soot marks with different heat ranges? Does the heat range affect the strap marks too?
Strap marks tell of the ignition timing i.e. the combustion, not heat range or the point of spark. The strap mark will move toward the base or tip depending upon the amount of heat that the engine puts into the plug, not the other way around. So if the engine has too much or too little fuel, it can raise or lower the engine's running temperature in relation to the timing. The fuel readings are on the plug's base ring - put 'How to read racing spark plugs - Dragstuff' into your search engine. There are more things that can change a plug's appearance - please see my reply to @Ben Sinor above.
Steve, can you put that used plug you read back in and read it again and get an accurate reading? say on the dyne, make another hit, shut It down and be able to see your adjustment/tuning?
Thank you for sharing ur time Mr Morris I was ignorant now I'm not so much LOL How abt plugs been in my old horse for year , Ny way of telling Ny thing from something like that or just for each run ?
I did some looking into this on TH-cam, my porcelain is completely white, and my strap is almost a zinc color goldish. I’m not sure what this means but there is no carbon buildup whatsoever after some hard driving on a big block Chrysler. I’m worried I’m too lean since I saw no carbon buildup.
Thank you Steve for that very informative video! You're the best , nobody else puts that content out there! I HAVE A QUESTION FOR YOU SIR, if I may. how do you decide on heat range for a spark plug? I would think that the particular build, forced induction, N/A, nitrous, type of fuel, would be part of the deciding factor?! Thank you for your time Steve!
Are you referring to a standard engine that could be found in an every day vehicle or a custom built engine from a performance shop? Your engine builder will tell you which spark plug he recommends you to try first!
Serious question . cross this over to a atv set up questioning the mid range with a adjustable needle . can the plug check still be done with a mid range chop ?
I see in a lot of you videos where you can see the afr's on the screen. Most seem in the 12.?. Is this an area of fueling you shoot for to start? Or where you end when reading a plug. I race at over a mile in elevation and it seems more like 11.2 to 11.5 run the best at the track. Thoughts
Many years ago when I was a kid and I was just a line mechanic on production cars, I was taught that the soot line would be moved by changing the 'temperature' or length of the electrode ceramic inside the threads. the idea was that a shorter plug could sink away the electrode heat easier than long one. So too much soot, the electrode is to cold ( or short ). No soot, then the plug was too hot (long). whether that is actually true or not was never proven to me since I just used what was called for. But you don't have that restriction. How did you determine what electrode length to use in your engines as it seems like that is a third variable that you have to standardize on in order to use the two tips you just gave.
The best spark plug reading video I’ve seen, thanks for explaining and cutting the threads off. Now I know what to look for.
Right, this nailed it.
Short, simple & perfect. Excellent job Steve
I've been watching car videos for years, and they'd talk about reading plugs, but never broke it down. I learned more in 5 minutes with this video than 5 plus years of watching car youtubers. Bravo!
never have I seen a better video or heard a better explanation on spark plug reading. Really Cool Steve!
The Steve Tech videos are accurate and very informative. Thank you Steve Morris for providing everyone in the automotive world with your wisdom, free of charge.
Great info as always. Could you touch on how/if different heat range plugs would have an effect on reading?
Yes, i would like to know more about that too :)
Me too. I assume the colder the plug is the better it is in the higher rpm’s.
Thanks for this video, finally a clear visual explanation of what lean really means! Subscribed
no truer words were ever spoken. I was taught this back in the 60s by a tune up guru. your exact explanation . All "tune them alls " tune via a lap top and dont wanna get there hands dirty. another good tool is a gas analizer, Co and HC under load tell a lot but most guys cant afford one and they cost a mint these days . I still have my old sun 111
5 and tuned 1000s of edelbrocks and hollys with it and reading plugs . you da man steve. Gawd I wish I were younger,
Gas analyzers have a problem. They measure only what is left over at the end when what you really need is the condition during actual combustion at +/- TDC where the power is actually made. The fuel continues to react even late in the stroke and in the exhaust ports even though it does nothing for power at that point. So they can easily give you a false impression. What you'd really like is a sample taken from the chamber at about 30 deg ATC.
Steve, I think you should do a video on "when to check your plugs". For example, I would make a pass and right at the 1/4 beams, pop the trans in neutral and shut the engine off. Tow back to the pits, let the engine cool and then pull plugs to take a reading.
Those (and more details) would really be helpful to your audience (in my opinion)
Thanks for all the GREAT videos!
Doesn’t have to be to the 1/4. Can just be a good 1 to 2 gear pull. Pull off to the side of the road shut the car off and pull one of the plug.
It’s a tedious process. But I did it. And I noticed a good difference in how my car reacts. Steve is smart af
The algorithm at its best I was just setting timing on fresh rebuild marine BBC. Going to pull a plug and see how I did. Thanks Steve
you know we take it for granted all the time like you said the data but then actually look at the physical spark plug is where you get the most accurate result thank you Steve
Thanks for this video I used this for tuning on my motorcycle and ended up with some great results.
Best video on how to read plugs 👍 Thank you Steve.
Excellent video, man. Love it. I used to watch the ol’ timers at the drag strip read there plugs with a jewelers eye loop. Now I know what they were reading.
Very well explained Can't explain it any better than this video
I really appreciate you sharing your knowledge on these videos I’ve never seen it explain this well before thank you
Learned something new. I always learned to inspect the tip, electrode, and threads when tuning. I need to do more. Thank you.
This was the best video I have ever seen explaining this!!!!
Great content sir! Thank you for the education. Headed out to the garage to cut apart all my plugs right now.
Just want to say thanks for putting this info out there this is a great video! I applied this process to the 364ci SBC I built and put in my nissan240sx Ended up taking 2 jets from the primary and 6 from the secondary on a proform 750dp. tuned for the leanest hottest cylinder got it perfect as I could and the old butt Dyno says it picked up 20-30hp everywhere but next trip to the strip will tell. Thanks again bud keep up the great work. I have known about your engines for years but think it's the greatest thing to actually learn something straight from one of the best have a good one brother!
More please. There’s got to me more to this. Thanks Steve. Best plug video I’ve seen.
Wow thanks. About half of what family members have told about looking plugs has turned out to be true. Now I’m going to go look at what top fuel plugs look like after a run just to see most extreme conditions.
I learned completely different information about reading plugs. Thank you
Your vids are awesome. You're my new engine Dad. Thanks for the knowledge man this is solid gold. Watched almost all of the tech vids twice now and I plan on watchin' 'em again and again
Master engine builder/ tuner right there. Thank you Mr Morris.
Dang Steve, In my 35+ years of tinkering with muscle cars off and on, I've never been told about cutting a plug open to look at the porcelain down inside. Just traded my 2012 Camaro for a 71 with a 383 and carb, so I'm definitely headed to a box store to get a 5/8" deep hole saw. Thanks!
Very nice explanation! Congrats
Back in the day, you'd look at "base ring" condition to assess carb mixture too. 👍 great vid Steve.
The Sparkplug. You're on. There was a time auto parts stores handed these out, Champion,
I'd like to see this again with samples of the failures and an ideal burn, including the heat range.
You have an excellent channel, thanks for sharing
Top vid Steve.
Thanks for this.
I would love a how to tune a carburetor video from you as well.
Excellent and clear cut video. Thanks Steve! 👍
This method is so cool.. can't wait to try it out. Thanks
Steve Thank you for that info I'm trying to tune my new carbs on my roots blower buy the spark plug on my 5th set of spark plug change almost there.
Thank you so much. This is a EXCELLENT tech video.
Man best video i have seen on this topic
Thanks steve, this information is gold.
Great video! Thanks, im going to try it for the first time tomorrow
If this legendary engine builder is gonna give me tips on ANYTHING automotive I'm downloading that video for future reference lol.
Why not just subscribe.
Great video, please make another one . Talk about heat range , Gap and boost. Thanks
very nice. very clear. you made it easy to understand. cheers steve
Right on Steve your the man and thank you for the info !
Awesome video. 👌🏾👌🏾👌🏾👌🏾
I need to start cutting some plugs up.
I just learned how to read a spark plugs!!! Thank you!!!!!! Awesome!!!!!
Sweet share it
To everyone you know
@@stevemorrisracing Would this plug reading process apply the same for a turbo motor?
For nitrous, does the plug read differently between NA and the hit? Which one do you tune by? Great video btw
Terrific video I had no idea. Thank you!!!
First 👍's up Steve M thanks again for taking us all along with you for the rest of the story
Hey Steve, appreciate your contribution to teaching us with info we would never find on the internet for free. I do have a couple of questions. Just curious what would be a good exh temp for an N.A, SBC 377 cuin drag motor with a set of hilborn mechanical fuel injectors on meth. The motor seems to want to nose over on the big end would that be the motor going lean. I have not applied what you have in this video but will the next time to the track. the fuel system has a high-speed bypass we can adjust by increasing or decreasing the pressure it pops off along with a jet we can change. The motor does not mis or pop when it noses over.
what would be a good exh temp we are seeing temps in the 1100 to 1130 range?
what is the difference in reading a gas vs. alcohol motor spark plug ?
Thanks for your help in advance.
Perfect explanation.
Man expand on this please. Heat range, thread coloring. Cruise tuning would be cool also.
Thread coloring doesn’t really matter. In fact it might add power. It’s using the threads further into the combustion chamber reducing the volume inside. I have about 2 rings on inside the combustion. Just like the this spark plug in the video
Can you make a video about Methanol tuning? Ideal lambda targets and what makes methanol different to tune. Thanks
Yes please, also why don’t nitrous guys run meth, seems they run some sort of gasoline.
@@jcnpresseryou don’t need nitrous with meth. You can run nitrometh. Best gas out there
great information. thanks. what about seing when you need a "hotter" or "colder" spark plug?
much respect, but no mention of spark plug heats because that is a lot to do with how much of that strap stays hot and burns that crust off the strap maybe he assumes you've already selected the correct heat of the spark plug but in my eyes it's one of the things you should read and adjust. again much respect as I've learned so much from you videos
This rocks! Thanks for the video
Yup this is right on. Back in the day this is all we had. Every body ran iron heads so pulling a plug out was no big. Be careful doing that on a hot alloy head.
Good time rich video. 😎
I used to work as a tech for a tuner that would burn the straps of plugs like they owed him money. Over the years I have learned that really good tuners are hard to find.
Nice detail on that.
Don't know if I will ever get to the point if cutting into a spark plug, but definitely will be looking a bit harder at them.
Who over ....say, 45 years old, does not read a plug?
Good video but forgot about how to determine heat range.
Also, what's your thought on champion or Autolite racing with cut back ground?
These are so awesome perfect learning tools
Thanks Steve, like others have mentioned before me, how does selecting a particular heat range play into this? Txs.
Doesn’t the 1st color of the threads mean something too? Can you touch on this. And this is a great video. Thanks for taking the time to do it
What about on a street engine? I get that with a drag car you want to make a WOT pull then check the plug. But that’s not how street engines are driven. How would you recommend this be performed with a street engine? Drive normally, with a couple WOT pulls, then check? Thanks! Loved the video!
I finally understand thank you great info
Another awesome, to the point, no b.s. proven tip.
Great explanation, but having different plugs to show the different examples would be nice 👍
This video is solid gold
Nice very important info
Great Video on the plugs!!!
How does the heat range effect the function, and how can you read if it´s a too hot or cold plug?
Thank you again! :)
Br Jonas in Sweden / BBF 429 cui / Hyd rollercam, alu heads, Edelbrock pro flo 4 , in a 1958 Edsel :)
Hi, You should have shown them a plug light and how it is used other then that excellent!
Steve, how does the heat range affect this? I would think for the same AFR, you could have different heights of the soot marks with different heat ranges? Does the heat range affect the strap marks too?
Strap marks tell of the ignition timing i.e. the combustion, not heat range or the point of spark. The strap mark will move toward the base or tip depending upon the amount of heat that the engine puts into the plug, not the other way around. So if the engine has too much or too little fuel, it can raise or lower the engine's running temperature in relation to the timing. The fuel readings are on the plug's base ring - put 'How to read racing spark plugs - Dragstuff' into your search engine.
There are more things that can change a plug's appearance - please see my reply to @Ben Sinor above.
Heat of plug is read by the color change on the threads.
Great video
Great Video!
Thanks!
Steve,
can you put that used plug you read back in and read it again and get an accurate reading? say on the dyne, make another hit, shut It down and be able to see your adjustment/tuning?
Can you do one explaining how adding or removing timing adds power
I would love to know if/how you can decipher the difference between an incorrect heat range plug and tuning issues.
Awesome thanks Steve
Does number of valves or the shape of the combustion chamber effect to plug coloring etc?
Thank you for sharing ur time Mr Morris I was ignorant now I'm not so much LOL How abt plugs been in my old horse for year , Ny way of telling Ny thing from something like that or just for each run ?
Great content thanks for sharing, very informative
NICE, excellent video. Thank you
Steve thank you for that!
Awesome SM!
Thanks for the solid info.
Great informative video! Worthy to put in my like file.
Great content Steve
Hey steve thanks for info your the man is there a rule of thumb on how to index spark plugs or is it a dyno thing,Kenny from McKinney, texas
what is your rule of thumb for plug gap on NA motors with higher compression?
I did some looking into this on TH-cam, my porcelain is completely white, and my strap is almost a zinc color goldish. I’m not sure what this means but there is no carbon buildup whatsoever after some hard driving on a big block Chrysler. I’m worried I’m too lean since I saw no carbon buildup.
Thank You Brother
Very informative, thank you.
Thank you Steve for that very informative video! You're the best , nobody else puts that content out there! I HAVE A QUESTION FOR YOU SIR, if I may. how do you decide on heat range for a spark plug? I would think that the particular build, forced induction, N/A, nitrous, type of fuel, would be part of the deciding factor?! Thank you for your time Steve!
Are you referring to a standard engine that could be found in an every day vehicle or a custom built engine from a performance shop? Your engine builder will tell you which spark plug he recommends you to try first!
@@NeverEnoughPyro40 did you not read what I posted?!
Thanks for the info!
Serious question . cross this over to a atv set up questioning the mid range with a adjustable needle . can the plug check still be done with a mid range chop ?
Steve how does heat range play a factor in that porcelain fat/lean line?A follow Q would be does this also apply to boost thanks for your time sir?
Steve, youre awesome man!!
I see in a lot of you videos where you can see the afr's on the screen. Most seem in the 12.?. Is this an area of fueling you shoot for to start? Or where you end when reading a plug. I race at over a mile in elevation and it seems more like 11.2 to 11.5 run the best at the track. Thoughts
Well explained...Cheers.
So just curious what does like nice brown mean ? Isn’t something that just means leaded race fuel or something else ?
Many years ago when I was a kid and I was just a line mechanic on production cars, I was taught that the soot line would be moved by changing the 'temperature' or length of the electrode ceramic inside the threads. the idea was that a shorter plug could sink away the electrode heat easier than long one. So too much soot, the electrode is to cold ( or short ). No soot, then the plug was too hot (long). whether that is actually true or not was never proven to me since I just used what was called for. But you don't have that restriction. How did you determine what electrode length to use in your engines as it seems like that is a third variable that you have to standardize on in order to use the two tips you just gave.
Trial and error
Thanks man, awesome video.
Thank-you Steve.
Wow awesome video great info🤙