Posted By: justinp61
Spark plug images - 06/24/14 04:38 AM
Anyone seen the strap look like this?
Spark plug images
Posted By: justinp61
Re: Spark plug images - 06/24/14 04:51 AM
These are out of my pump 93 10.9-1 408. I've taken the carb back to close to the original set up. At cruise, 3000 rpms the afr is 13.0-13.4. From a dead stop I pulled wide open to 6100 in high and the afr was 12.6-12.8 except when it was spinning in first and second gears until it hooked at 5200. When it was spinning the afr was 13.6-13.9. When it hooked the afr went to 12.4.
Posted By: justinp61
Re: Spark plug images - 06/24/14 04:53 AM
Last one.
Posted By: Cab_Burge
Re: Spark plug images - 06/24/14 07:59 AM
If those where brand new and you drove it a very short distance before taking these pictures I would try the next step colder plugs, maybe two steps colder and see how those look 
If those have been driven a lot longer than a short time definitely go to a colder plug
If those have been driven a lot longer than a short time definitely go to a colder plug
Posted By: justinp61
Re: Spark plug images - 06/24/14 12:10 PM
Cab, they were new. I set the idle mixture and took it for a ride, probably four miles at the most. with the exception of the wide open blast most of the time was spent at 2800-3300,NGK 7s.
Posted By: Quicktree
Re: Spark plug images - 06/24/14 12:19 PM
plugs to hot and to lean, but if you didn't do a shut off pass it's hard to get a good read.
http://www.youtube.com/watch?v=fiMM2S0aADM
http://www.youtube.com/watch?v=fiMM2S0aADM
Posted By: slammedR/T
Re: Spark plug images - 06/24/14 04:10 PM
I assume that is an extended reach plug in the zrf series? if so prolly try 4554 #8 race plug from NGK, they are cheaper at speed shops. $18.75 for a set of 8 here in jax at my speed shop I use.
Posted By: justinp61
Re: Spark plug images - 06/24/14 04:33 PM
The plugs are BRK7E, #4644.
Posted By: slammedR/T
Re: Spark plug images - 06/24/14 04:38 PM
Quote:
The plugs are BRK7E, #4644.
OH, I didn't know the BRK's were also extened tip. anyway my 408 is at 10.5:1 compression and I run the 4554 plugs with no issue even on a 200 shot of juice.
Posted By: sixpackgut
Re: Spark plug images - 06/24/14 07:02 PM
you need to take it to the track or a dyno and start jetting up then see what the AF meter says. don't go by that thing till you know what the engine wants. I wouldn't be buying plugs till you feel carb is tuned. I think -7 will be just fine. In my engine, those plugs would be way lean
Posted By: justinp61
Re: Spark plug images - 06/25/14 04:14 AM
Today I jetted the primaries up two numbers and dropped the high speed bleeds two sizes and will drive it with the same plugs tomorrow afternoon when I get off work.
Thanks guys.
Thanks guys
.
Posted By: Thumperdart
Re: Spark plug images - 06/25/14 05:01 AM
Quote:
Today I jetted the primaries up two numbers and dropped the high speed bleeds two sizes and will drive it with the same plugs tomorrow afternoon when I get off work.
Thanks guys
This may help based on the wide jet spread you`re running and those plugs aren`t too hot for your compression in my opinion since I ran em at 12.1.1 comp. but like the 8`s better now that the carb`s tuned. Measure your pvcr`s then that will help you determine the proper jet spread.................
Posted By: justinp61
Re: Spark plug images - 06/25/14 12:14 PM
Quote:
Measure your pvcr`s then that will help you determine the proper jet spread.................
I have a set of 1-60 and 61-80 drill bits on the way.
Posted By: Quicktree
Re: Spark plug images - 06/25/14 12:27 PM
Quote:really, what is the ground strap telling you?Quote:
Today I jetted the primaries up two numbers and dropped the high speed bleeds two sizes and will drive it with the same plugs tomorrow afternoon when I get off work.
Thanks guys
This may help based on the wide jet spread you`re running and those plugs aren`t too hot for your compression in my opinion since I ran em at 12.1.1 comp. but like the 8`s better now that the carb`s tuned. Measure your pvcr`s then that will help you determine the proper jet spread.................
Posted By: justinp61
Re: Spark plug images - 06/25/14 01:23 PM
really, what is the ground strap telling you?
I don't honestly know, that's why I posted the photos. I'll have to order a set of 8s.
Posted By: jlatessa
Re: Spark plug images - 06/25/14 03:19 PM
Posted By: cudadon
Re: Spark plug images - 06/25/14 03:22 PM
Quote:really, what is the ground strap telling you?
I don't honestly know, that's why I posted the photos. I'll have to order a set of 8s.
I would say the strap is saying the temp in the chamber is high.
Needs more fuel, less timing or a combination of both.
Don
Posted By: Thumperdart
Re: Spark plug images - 06/25/14 04:40 PM
Quote:Quote:really, what is the ground strap telling you?Quote:
Today I jetted the primaries up two numbers and dropped the high speed bleeds two sizes and will drive it with the same plugs tomorrow afternoon when I get off work.
Thanks guys
This may help based on the wide jet spread you`re running and those plugs aren`t too hot for your compression in my opinion since I ran em at 12.1.1 comp. but like the 8`s better now that the carb`s tuned. Measure your pvcr`s then that will help you determine the proper jet spread.................
Not clear enuff to read the strap but based on our phone conversations, he needs to measure the pvcr`s to get a feel for the jet spread cos a 12 spread and small pvcr`s could be creating the lean that I see.............but what do I know.
Posted By: Crizila
Re: Spark plug images - 06/25/14 05:11 PM
Quote:
plugs to hot and to lean, but if you didn't do a shut off pass it's hard to get a good read.
http://www.youtube.com/watch?v=fiMM2S0aADM
That's what I will be doing this Saturday at the track. Besides reading plugs, I temporarily mounted my camera so that I can record A/F and boost gauge readings at WOT.
Posted By: Quicktree
Re: Spark plug images - 06/25/14 05:19 PM
Quote:really, what is the ground strap telling you?
I don't honestly know, that's why I posted the photos. I'll have to order a set of 8s.
go watch the video i posted and come back and report, the message is clear.
Posted By: jp15
Re: Spark plug images - 06/25/14 06:25 PM
same material I've went by for years Quicktree .
.
Posted By: Thumperdart
Re: Spark plug images - 06/25/14 06:54 PM
Quote:Quote:really, what is the ground strap telling you?
I don't honestly know, that's why I posted the photos. I'll have to order a set of 8s.
go watch the video i posted and come back and report, the message is clear.
Not sure about a clear message but I dig the jazzy groove........
Posted By: bwhackd34
Re: Spark plug images - 06/25/14 10:59 PM
wrong heat range, WAY too lean, WAY too much timing...initial and total and maybe even too much gap......
Posted By: justinp61
Re: Spark plug images - 06/26/14 04:19 AM
I made some changes to the carb this week and took it for a spin today. I went from 76/88 jets and 31/71 air bleeds to 78/88 jets and 29/71 air bleeds. Idle afr was 14.3-14.8, 3000 rpm cruise was 12.3-12.5 and wot was 12.4-12.6. The plugs have color now, I'd guess from being rich at cruise where it spent most time at. I'll order some ngk 8s, for now I'll put in a set of Autolite AR3934 after I work on the cruise.
2,4,6 & 8.
2,4,6 & 8.
Posted By: Crizila
Re: Spark plug images - 06/26/14 06:17 AM
Quote:They look better. I am running R5671A-8 NGK's and thinking about switching to AR3934's. They are a direct cross.
I made some changes to the carb this week and took it for a spin today. I went from 76/88 jets and 31/71 air bleeds to 78/88 jets and 29/71 air bleeds. Idle afr was 14.3-14.8, 3000 rpm cruise was 12.3-12.5 and wot was 12.4-12.6. The plugs have color now, I'd guess from being rich at cruise where it spent most time at. I'll order some ngk 8s, for now I'll put in a set of Autolite AR3934 after I work on the cruise.
2,4,6 & 8.
Posted By: Cab_Burge
Re: Spark plug images - 06/26/14 06:31 AM
Quote:If you didn't put new plugs in before doing the carb. tuning you should.
I made some changes to the carb this week and took it for a spin today. I went from 76/88 jets and 31/71 air bleeds to 78/88 jets and 29/71 air bleeds. Idle afr was 14.3-14.8, 3000 rpm cruise was 12.3-12.5 and wot was 12.4-12.6. The plugs have color now, I'd guess from being rich at cruise where it spent most time at. I'll order some ngk 8s, for now I'll put in a set of Autolite AR3934 after I work on the cruise.
2,4,6 & 8.
The two plugs on the left are fatter than needed, the one next to the last one on the right side and especially the last one on the right are close to what I like to see When it comes to tuning, lean is mean and cold sprak plugs that don't foul at part throttle are just right 
Posted By: Thumperdart
Re: Spark plug images - 06/26/14 07:31 AM
Quote:Quote:They look better. I am running R5671A-8 NGK's and thinking about switching to AR3934's. They are a direct cross.
I made some changes to the carb this week and took it for a spin today. I went from 76/88 jets and 31/71 air bleeds to 78/88 jets and 29/71 air bleeds. Idle afr was 14.3-14.8, 3000 rpm cruise was 12.3-12.5 and wot was 12.4-12.6. The plugs have color now, I'd guess from being rich at cruise where it spent most time at. I'll order some ngk 8s, for now I'll put in a set of Autolite AR3934 after I work on the cruise.
2,4,6 & 8.
You may need 8`s w/your combo but not sure Justin does and now the heat/timing band looks better but I could be wrong.............
Posted By: bwhackd34
Re: Spark plug images - 06/26/14 11:26 AM
look a little better...still too much timing and wrong heat range....
Posted By: justinp61
Re: Spark plug images - 06/26/14 12:16 PM
The timing is 21 initial and 34 total. I've got to work on the cruise then I'll repost some photos.
Posted By: Thumperdart
Re: Spark plug images - 06/26/14 06:09 PM
Quote:
look a little better...still too much timing and wrong heat range....
I guess different guys read em differently...........years ago the heat range was measured(by some)as the amount of threads colored going up the plug as seen from the ground strap ie; 2-3 threads was considered good 1 too cold 5 too hot. I know when I went to a colder plug the band on the ground strap mover farther out towards the end.
Posted By: Quicktree
Re: Spark plug images - 06/26/14 10:26 PM
Quote:go watch the video i posted and learn you some of this new technologyQuote:
look a little better...still too much timing and wrong heat range....
I guess different guys read em differently...........years ago the heat range was measured(by some)as the amount of threads colored going up the plug as seen from the ground strap ie; 2-3 threads was considered good 1 too cold 5 too hot. I know when I went to a colder plug the band on the ground strap mover farther out towards the end.
Posted By: MR_P_BODY
Re: Spark plug images - 06/26/14 10:37 PM
Quote:Quote:go watch the video i posted and learn you some of this new technologyQuote:
look a little better...still too much timing and wrong heat range....
I guess different guys read em differently...........years ago the heat range was measured(by some)as the amount of threads colored going up the plug as seen from the ground strap ie; 2-3 threads was considered good 1 too cold 5 too hot. I know when I went to a colder plug the band on the ground strap mover farther out towards the end.
If you want Tony I can show you other sites that
say the ground strap is timing.. and I can move the
blue line with the timing... that changes the heat
in the cyl also... let me know if you want me to post it
Posted By: Quicktree
Re: Spark plug images - 06/26/14 10:44 PM
i have seen that, who is the author? thats what you want to find out? how can timing make the band on the ground strap move?
Posted By: MR_P_BODY
Re: Spark plug images - 06/26/14 11:15 PM
Quote:
i have seen that, who is the author? thats what you want to find out? how can timing make the band on the ground strap move?
This guys have a bit of knowledge
http://www.4secondsflat.com/Spark_plug_reading.html
Posted By: Quicktree
Re: Spark plug images - 06/26/14 11:25 PM
what ever you want to believe i guess, i can see timing changing exhaust gas temp but don't see how it can change the ground strap. the only thing that can change that is the plug heat range imo.
Posted By: MR_P_BODY
Re: Spark plug images - 06/26/14 11:30 PM
Quote:
what ever you want to believe i guess, i can see timing changing exhaust gas temp but don't see how it can change the ground strap. the only thing that can change that is the plug heat range imo.
I guess you can think the way you want... I'll stay
with what I and many others think also... so we will
call it equal... hows that
Posted By: Quicktree
Re: Spark plug images - 06/26/14 11:43 PM
fine with me I still would like you to explain how it can single out the ground strap and change it.
I still would like you to explain how it can single out the ground strap and change it.
Posted By: MR_P_BODY
Re: Spark plug images - 06/26/14 11:58 PM
Quote:
fine with me
Simple... start the burn earlier and the temp in
the cyl goes up... if its later it cooler and burns
more in the pipes... I have backed the timing down
on my junk and seen the color move closer to the tip
of the radius on the strap... this is fact not just a
opinion
Posted By: Crizila
Re: Spark plug images - 06/27/14 12:17 AM
Quote:Quote:
fine with me
Simple... start the burn earlier and the temp in
the cyl goes up... if its later it cooler and burns
more in the pipes... I have backed the timing down
on my junk and seen the color move closer to the tip
of the radius on the strap... this is fact not just a
opinion
but don't loose sight of the fact that we are not adjusting timing or A/F to make the plugs look happy. Gotta make adjustments in those areas for best HP or at the track, best MPH. Then correct plug choice so they are happy and live for a while - which I can't seem to accomplish. 
Posted By: MR_P_BODY
Re: Spark plug images - 06/27/14 12:44 AM
Quote:Quote:Quote:
fine with me
Simple... start the burn earlier and the temp in
the cyl goes up... if its later it cooler and burns
more in the pipes... I have backed the timing down
on my junk and seen the color move closer to the tip
of the radius on the strap... this is fact not just a
opinion
I know your playing with a boosted engine so on yours
are the plugs fouling out or burning up
Posted By: GTX MATT
Re: Spark plug images - 06/27/14 12:57 AM
Heres a silly question - does it matter if you do a shut down run right before reading the plugs if you're looking at the ground strap for a timing indicator?
If not then I would say it has more to do with the timing and not the effects of changing the timing (i.e. EGT)
If not then I would say it has more to do with the timing and not the effects of changing the timing (i.e. EGT)
Posted By: MR_P_BODY
Re: Spark plug images - 06/27/14 01:01 AM
Quote:
Heres a silly question - does it matter if you do a shut down run right before reading the plugs if you're looking at the ground strap for a timing indicator?
If not then I would say it has more to do with the timing and not the effects of changing the timing (i.e. EGT)
Its much easier to read a true reading on a shut down
run.. its more pronounced
Posted By: GTX MATT
Re: Spark plug images - 06/27/14 01:05 AM
Will it usually stay in the same spot though?
Posted By: MR_P_BODY
Re: Spark plug images - 06/27/14 01:12 AM
Quote:
Will it usually stay in the same spot though?
From what I have seen .. yes if the timing wasnt changed
but if you reduce the timing its gonna end up with
a wider burn mark and its usually better to start with
fresh plugs.. but I usually just put in 1 or 2 plugs
for a reading then if it looks better/right then I
change the rest to get a full engine reading
Posted By: GTX MATT
Re: Spark plug images - 06/27/14 01:13 AM
Good to know, I've been wondering about this.
Posted By: MR_P_BODY
Re: Spark plug images - 06/27/14 01:19 AM
Quote:
Good to know, I've been wondering about this.
I pulled 2 plugs today on my street rod... seen that
I'm a couple degrees high on timing and its still rich..
I checked them because I'm going on a run tomorrow
with a lot of X-way running and I wanted to make sure
I wasnt lean.. I pulled 2 degrees of timing and left
it on jetting till after tomorrow
Posted By: Crizila
Re: Spark plug images - 06/27/14 04:10 AM
Quote:Right now they are fouling out Mike. I can get about 4 - 5 runs on a set of plugs before I start to experience a high boost miss. Pretty sure I am way rich, but won't know until Saturday when I can make some WOT runs at the track without the exhaust system on it. Camera should tell all ( pointed at the A/F and boost gauges), plus I will be able to cut it off clean at the end to examine the plugs properly. I'm running 110 leaded gas.Quote:Quote:Quote:
fine with me
Simple... start the burn earlier and the temp in
the cyl goes up... if its later it cooler and burns
more in the pipes... I have backed the timing down
on my junk and seen the color move closer to the tip
of the radius on the strap... this is fact not just a
opinion
I know your playing with a boosted engine so on yours
are the plugs fouling out or burning up
Posted By: Crizila
Re: Spark plug images - 06/27/14 04:14 AM
Quote:Yes, but the more you put around, the less clear it will be to read.
Will it usually stay in the same spot though?