Reading Sparkplugs

Here is how you properly read a spark plug. If you want to learn how to tune any engine WATCH this video!

[@jcnpresser]

The best spark plug reading video I’ve seen, thanks for explaining and cutting the threads off. Now I know what to look for.

[@Scarred.13]

Right, this nailed it.

[@nukedogger86]

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!

[@kevhauser]

never have I seen a better video or heard a better explanation on spark plug reading. Really Cool Steve!

[@LetsGoYall]

Great info as always. Could you touch on how/if different heat range plugs would have an effect on reading?

[@bikeclochard]

Thanks for this video, finally a clear visual explanation of what lean really means! Subscribed

[@tjsingh5163]

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

[@Jim-Penn]

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!

[@tomtucker8849]

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.

[@rickwallace5582]

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,

[@billshiff2060]

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.

[@dougankrum3328]

The Sparkplug. You're on. There was a time auto parts stores handed these out, Champion,

[@95turbostang21]

Very well explained Can't explain it any better than this video

[@musixvideox5704]

Figured you would talk about different deposits build up etc. But this was useful also

[@MrShakotan]

Thank you so much. This is a EXCELLENT tech video.

[@chrismadaj8751]

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

[@davidgretlein9384]

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.

[@ShawnDickens]

Man expand on this please. Heat range, thread coloring. Cruise tuning would be cool also.

[@rafaelleao79]

Very nice explanation! Congrats

[@Dontdelete420]

This method is so cool.. can't wait to try it out. Thanks

[@jimcallicoat]

I really appreciate you sharing your knowledge on these videos I’ve never seen it explain this well before thank you

[@Scarred.13]

Perfect explanation.

[@drakeolson2539]

This was the best video I have ever seen explaining this!!!!

[@benausman8444]

Best video on how to read plugs 👍 Thank you Steve.

[@scottgarmon4865]

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.

[@z06doc86]

More please. There’s got to me more to this. Thanks Steve. Best plug video I’ve seen.

[@zx6rkawi09]

Man best video i have seen on this topic

[@besearchingforwisdom6267]

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

[@nikoc.7574]

Thanks steve, this information is gold.

[@Tracked350Z]

Learned something new. I always learned to inspect the tip, electrode, and threads when tuning. I need to do more. Thank you.

[@Intellistan]

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

[@mynameis63]

Master engine builder/ tuner right there. Thank you Mr Morris.

[@ViperSRTnACR]

Excellent and clear cut video. Thanks Steve! 👍

[@devinmcalister1239]

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!

[@dsauce8780]

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.

[@JG-zb7om]

Great content sir! Thank you for the education. Headed out to the garage to cut apart all my plugs right now.

[@tch632]

Back in the day, you'd look at "base ring" condition to assess carb mixture too. 👍 great vid Steve.

[@Hogiewan1]

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!

[@johnbowen2963]

very nice. very clear. you made it easy to understand. cheers steve

[@vandettabuilds6641]

Terrific video I had no idea. Thank you!!!

[@steveallam]

Nice very important info

[@josh22886]

Great video! Thanks, im going to try it for the first time tomorrow

[@davoupnya3202]

Right on Steve your the man and thank you for the info !

[@prostreethustler239]

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.

[@danielsullivan9865]

Great video, please make another one . Talk about heat range , Gap and boost. Thanks

[@stevegirard817]

I just learned how to read a spark plugs!!! Thank you!!!!!! Awesome!!!!!

[@stevemorrisracing]

Sweet share it To everyone you know

[@haatch999]

These are so awesome perfect learning tools

[@jaysfasttoys]

NICE, excellent video. Thank you

[@TurbineResearch]

Can you make a video about Methanol tuning? Ideal lambda targets and what makes methanol different to tune. Thanks

[@jcnpresser]

Yes please, also why don’t nitrous guys run meth, seems they run some sort of gasoline.

[@JohnRoberts71]

Great content thanks for sharing, very informative

[@nickhoffman5524]

Great content Steve

[@danielsmith-ze3wy]

Awesome thanks Steve

[@garagehack2060]

Great informative video! Worthy to put in my like file.

[@toddheath123]

Very informative, thank you.

[@momentummotorsports6137]

I finally understand thank you great info

[@turbovolvos40]

Awesome video

[@johnbuchanan6045]

Thanks for the info!

[@johnrichardson82]

Great video

[@DaleTerry]

Steve thank you for that!

[@dondagy9109]

Another awesome, to the point, no b.s. proven tip.

[@dallynsr]

Awesome SM! Thanks for the solid info.

[@robperrin9497]

Thanks man, awesome video.

[@bigredracer7848]

First 👍's up Steve M thanks again for taking us all along with you for the rest of the story

[@brendanmccarthy492]

Thanks Steve!!!

[@cbr1thou]

Steve, youre awesome man!!

[@hoekstratechniek]

This video is solid gold

[@GHST-vy3nk]

Thank You Brother

[@henrysmith8012]

Thank you Steve.

[@justaray]

Thank-you Steve.

[@MrJamie1978]

Great video!

[@ronalddrummond4580]

Wow awesome video great info🤙

[@tommy.oyukio4811]

Thank you ... great INFO....

[@dennis1954]

Thank you for the info.

[@ziggassedup]

Well explained...Cheers.

[@bubbakushingtonIII]

If this legendary engine builder is gonna give me tips on ANYTHING automotive I'm downloading that video for future reference lol.

[@Dougarrowhead]

Why not just subscribe.

[@trentm7964]

Thanks Steve!

[@travispeoples]

Good time rich video. 😎

[@yeboscrebo4451]

Awesome, thanks

[@waylonrichter7270]

Thanks Steve

[@martinvestergaard6707]

great information. thanks. what about seing when you need a "hotter" or "colder" spark plug?

[@prcdjhnsn]

Good video but forgot about how to determine heat range. Also, what's your thought on champion or Autolite racing with cut back ground?

[@gilmauldin6590]

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.

[@SoDogtravels]

Thank you

[@grantk.3860]

Thank you🙏

[@RAWRMotorsports]

AWESOME VIDEO ✌🤘👍💥

[@jasonwalter5873]

Great explanation, but having different plugs to show the different examples would be nice 👍

[@keithdaniels1994]

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.

[@ThePeopleVerse]

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?

[@kennykirby8606]

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

[@brianb5779]

Steve do you have any carb tuning videos as well? And by the way this info is gold

[@donbenson2099]

Hi, You should have shown them a plug light and how it is used other then that excellent!

[@davechambers2730]

Awesome

[@scottyjones27]

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 ?

[@jacobnewtron9635]

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

[@rayjay6769]

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!

[@NeverEnoughPyro40]

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!

[@rayjay6769]

@@NeverEnoughPyro40 did you not read what I posted?!

[@86FxBdyCpe]

Thanks Steve, like others have mentioned before me, how does selecting a particular heat range play into this? Txs.

[@thomasvittetoe1930]

Can you do one explaining how adding or removing timing adds power

[@scottk2342]

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?

[@onedayiwillmakesomecontent]

Steve can you please tell us about header length etc, pulse frequency/scavenge for NA and boosted?

[@johnnyhonda7576]

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

[@davidreed6070]

Good I got a different angle at plug reading

[@brendavanorden9550]

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