Reading Spark Plugs - A Discussion
 

http://i267.photobucket.com/albums/i...414_174207.jpg

been doing this a while now, just making sure im looking at the right thing. the "color change" that denotes the timing mark, is that the first white to grey line thats right on the bend of the plug, or is it the grey to light grey line thats real close to the base ring of the plug? this plug was from a 3rd gear pull. i shut the engine down @wot at 6500 rpm and coasted off the road to check the plugs. there was evidence of detonation on the porcelain, from just below the electrode to just about where the porcelain goes down into the threaded portion. plug had maybe 15 miles on it and this was the first wot hit.

re: Reading Spark Plugs - A Discussion
 

timing mark is that darkest line right at the bend ... looks good to me maybe a touch hot but its in the bend which is good..

now it looks a bit lean you need to cut the sparkplug thread and show the base of the porcelain that will show fuel ring

re: Reading Spark Plugs - A Discussion
 

Delete

re: Reading Spark Plugs - A Discussion
 

afr was 12.5-12.7 at engine shutdown. there were a few silver flaky specs on the porcelain since they were up on the porcelain my experience tells me it was from low to medium load...

re: Reading Spark Plugs - A Discussion
 

Edited

re: Reading Spark Plugs - A Discussion
 

nice thanks man!

so before you run the plugs in the first place, you sand the ground strap, then toss the plugs in after cleaning and do your pulls. just verifying.

i moved the cam gears around a bit today and its a whole new animal. damn that virtual dyno it keeps me messing with it cuz its easy rather than just go to a real dyno lol

re: Reading Spark Plugs - A Discussion
 

It's probably due. To that afr. You see that guys base ring how it looks that how your should look. But basically you need to cut the threads off so I can see the fuel ring at the bottom of the porcelain. Your timing mark looks fine !! It's prolly a little hot do to being lean at wot 12.5-12.7 at wot isn't what I'd be happy with

re: Reading Spark Plugs - A Discussion
 

Bye

re: Reading Spark Plugs - A Discussion
 

I'm curious what u did with the cam gears ? I'm running stock cam gears and I know they are retarded like 2 degs or so on both sides. Due to decking

I'm just wondering if I should get gears to advance and bring back to straight up

re: Reading Spark Plugs - A Discussion
 

I advanced the intake cam 2 degrees. i lost the peak in the power but it seems to have spread it out making a broader powerband. im gonna retard the ex. cam a lil amd see if I can find a compromise between peak and breadth. i had to add 3-5% more fuel into the map with the intake cam advance for what its worth.


hatchy- sounds good ive got extra plugs ill do some sanding and pulls over the weekend.

re: Reading Spark Plugs - A Discussion
 

Thank you for posting this! I'm gonna try it. I've never been able to see the color change on my plugs like this pic shows.

re: Reading Spark Plugs - A Discussion
 

so im taking it that 12.5 is lean for a 10.8: static 82x89mm vtec? certainly not the impression i was under. this isnt some monster motor here, its pretty close to being an itr, even running itr cams. that afr sound ok to the general consensus?

how do u guys clean plugs? be nice if i could use them for some pulls then clean them off to keep the porcelain fresh. btw these are bkr6e's gapped at about .035"

re: Reading Spark Plugs - A Discussion
 

Bye

re: Reading Spark Plugs - A Discussion
 

12.5 is not lean at all

re: Reading Spark Plugs - A Discussion
 

I can't wait to get some time to try this method out. I have read about doing this before, but I didn't know it would make such a difference in how obvious the timing mark would be. Are you seeing the blue timing mark on the strap slowly creep closer to the base as you add timing? In the pic you timing mark definitely looks to be on the conservative side. Do you use anything else to clean the plug like carb cleaner or something or just lightly sand the strap?

I'll post up some pics of my plugs when I get some time to do this. Im really interested in seeing how much the blue timing mark moves with changes in the timing map.

re: Reading Spark Plugs - A Discussion
 

I'm sorry I was under the impression it was a boosted setup. I would go with a bkr7e for that setup anyhow

re: Reading Spark Plugs - A Discussion
 

^^ its all good man no worries.

re: Reading Spark Plugs - A Discussion
 

did a pull with some sanded plugs.

http://i267.photobucket.com/albums/i...419_110556.jpg
just to double check, im looking at the area right before the end of the ground strap where it goes from blue to gold right? its just before the bend right above the porcelain. there is another "cleaner" line way down toward the base of the ground strap, thats not what i want correct?


heres a few more shittier pics
http://i267.photobucket.com/albums/i...419_110458.jpg
http://i267.photobucket.com/albums/i...419_110737.jpg

re: Reading Spark Plugs - A Discussion
 

Bye

re: Reading Spark Plugs - A Discussion
 

thanks for the reply dude. i think ive dropped my phone one too many times the camera doesnt focus in up close like it used to. either way my blue to gold transition is before the bend on the ground strap. looks like it could use 1-2 more degrees. had an issue come up with the neptune in the car today, so i think continuing the street tuning is gonna take a break for a bit. thanks again

re: Reading Spark Plugs - A Discussion
 

Bye

re: Reading Spark Plugs - A Discussion
 

I bet your car feels a lot faster now too. I know what you mean about people being very vague about answering tuning questions. I'm gonna try to get out and do some tuning this week and I'll be sure to post pics of my plugs when I do.

re: Reading Spark Plugs - A Discussion
 

Yeah made a big difference

re: Reading Spark Plugs - A Discussion
 

your not kidding about answering questions. sometimes I feel that I just need to know if im in the ballpark with stuff since every car is different.

ive been using virtual dyno its certainty helpful but I still feel like there are variables in road conditions etc

re: Reading Spark Plugs - A Discussion
 

Got a chance to get out and try this sanded ground strap thing out. I'm amazed at how clear you can see the timing mark now. I used a brand new set of ngk 4554 8 heat range plugs. I lightly sanded the coating off of just the ground strap. I only drove about a mile and got into boost a few times before I made a full 3rd gear pull and shut it off at redline. I was shooting for about 15.5psi but ended up hitting 17psi because of my pwm iat correction was a little off. I haven't driven in weather as warm as it was today. You can see from the data log below that table timing is 10.5* and actual timing is 18.5* based on how the plugs read this is a little too conservative. I added 2 degrees of timing and when I get another chance I'll do this again and see how the plugs read. I want to stay on the conservative side because it's basically a stock ls with Nippon pistons and stock rods with arp fasteners. I'm on 92 octane pump gas too.

I hope this helps out some other diy tuners like myself. Thanks for the tip on sanding the ground strap turbohatch96y7! I have read that multiple times, but I guess I just needed to see someone else do it before I tried it lol.




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