DETONATION

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redliner
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Re: DETONATION

Post by redliner »

Tuner wrote: Sat May 19, 2018 12:08 pm First, detonation makes tiny black specks. if you see silver color beads the source is more likely preignition, which can occur without detonation. Preignition results in extreme heat which initially distills metallic vapor of lower temperature melting alloy from the piston before actually catastrophically melting big gobs of aluminum. Detonation can occur and make the black specks without vaporizing or melting any metal from the piston.

On the other hand, if an engine ingests an astonishingly small amount of dust you may see what looks to be detonation. The color and appearance of this type of tiny specks depends on the mineral content of the local dirt or source of the dust. The trace minerals (metals) in the silica melt and fuse into tiny beads which can imitate detonation specs. Some fabric gauze air filters (K&N type) are perfect sifters to admit just the right size bits of dust to make the imitation detonation specks.

Many new cylinder heads have significantly improved "fast burn" combustion characteristics and require much less ignition advance than earlier stuff. You need to retard timing until performance begins to drop off to find the least advance that gives the best performance. Don't be surprised if it is less than 30 degrees for some new chamber and port designs.
Fresh combo... could have some stuff floating around. Thanks!
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Re: DETONATION

Post by redliner »

n2xlr8n wrote: Sat May 19, 2018 12:58 pm I second the anti-sieze.

I also like to make sure my fuel volume / pressure to the carb is good when a sorted combination is not performing as expected.

.02 from an amateur. :lol:
I was doing that last night thanks!
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Re: DETONATION

Post by redliner »

Scotthatch wrote: Sat May 19, 2018 1:10 pm I have a couple of thoughts

Can you post a photo of a plug so we can see?

Have tried pulling 4 degrees out and seeing how it effects your ET?
I have never been able to get pics on here... I pulled 2 degrees out and it fell off almost 3 mph!
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Re: DETONATION

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Scotthatch wrote: Sat May 19, 2018 1:42 pm
n2xlr8n wrote: Sat May 19, 2018 1:25 pm
Scotthatch wrote: Sat May 19, 2018 1:10 pm I have a couple of thoughts

Can you post a photo of a plug so we can see?

Have tried pulling 4 degrees out and seeing how it effects your ET?
He stated " I ran 1st pass 35 degrees timing 100 octane aviation fuel( 110 jet front and rear ) it ran 129.18 mph trap speed in 1/4 mile drags. I bumped timing back to 33 degrees 100 octane( 110 jet ) after seeing 1 speck of shiny aluminum(?) on only # 1 plug (with 10 power magnification) mph dropped to 126.55"

That sort of (not always) shoots my fuel volume question in the foot.
It also says timing is about right .... I am assuming the timing is fixed ?
Yes, crank trigger. Thanks.
Last edited by redliner on Sat May 19, 2018 4:00 pm, edited 2 times in total.
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Re: DETONATION

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NormS wrote: Sat May 19, 2018 3:30 pm #7 NGK plugs may be a bit too warm. I suggest using a #9 NGK plug.
I wondered that! I have some new 8s what do ya think?
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Re: DETONATION

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redliner wrote: Sat May 19, 2018 8:57 am... I cannot get pics to show up here but maybe I can take some pictures of them and send them to someones email who would be willing to look at them? THANKS!
When you're typing a reply, there is box with four bars to the right of the word "Options" below the reply box.
Click on it and the word "Attachments" appears.
Click on that and a box labelled "Add files" appears.
Click on it and it will take you to your computer's picture file or something similar.
Click on the image/images you want and then click the 'open' box.
The pic's title will appear in a box below the reply box.
Click on the "Place inline" tab and it should appear in your reply box.
(I've attached a random pic to verify these steps.)
Piece of cake, eh? :shock: :lol:
.
.
NASCAR Piston 003.JPG
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Felix, qui potuit rerum cognscere causas.

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Re: DETONATION

Post by groberts101 »

MadBill wrote: Sat May 19, 2018 5:38 pm
redliner wrote: Sat May 19, 2018 8:57 am... I cannot get pics to show up here but maybe I can take some pictures of them and send them to someones email who would be willing to look at them? THANKS!
When you're typing a reply, there is box with four bars to the right of the word "Options" below the reply box.
Click on it and the word "Attachments" appears.
Click on that and a box labelled "Add files" appears.
Click on it and it will take you to your computer's picture file or something similar.
Click on the image/images you want and then click the 'open' box.
The pic's title will appear in a box below the reply box.
Click on the "Place inline" tab and it should appear in your reply box.
(I've attached a random pic to verify these steps.)
Piece of cake, eh? :shock: :lol:
.
.

NASCAR Piston 003.JPG
Hi Bill. Is that the line 2 line coating?

And what's on top? Never seen a black TBC before.

And while I'm at it.. is that the actual tape job they did to coat the crowns?
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Re: DETONATION

Post by Warp Speed »

NormS wrote: Sat May 19, 2018 3:30 pm #7 NGK plugs may be a bit too warm. I suggest using a #9 NGK plug.
Ya, people seem to want to run the hottest plug they can, when really they should be running the coldest plug they can, without fouling or misfire that is.
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Re: DETONATION

Post by cjperformance »

Warp Speed wrote: Sat May 19, 2018 7:47 pm
NormS wrote: Sat May 19, 2018 3:30 pm #7 NGK plugs may be a bit too warm. I suggest using a #9 NGK plug.
Ya, people seem to want to run the hottest plug they can, when really they should be running the coldest plug they can, without fouling or misfire that is.
Yes ^^ start cold and work 'toward' the hotter side - not melt stuff then back it off!
And only change 1 thing at a time (unless you are sure you will kill the engine!) to get an idea of what each change does and an easy reversal if the change was no good because you know what did what.
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Re: DETONATION

Post by MadBill »

groberts101 wrote: Sat May 19, 2018 7:29 pm
Hi Bill. Is that the line 2 line coating?

And what's on top? Never seen a black TBC before.

And while I'm at it.. is that the actual tape job they did to coat the crowns?
it's a ~15 year old Ford Cup piece that came from a shop that builds engines mostly from used Cup parts; I don't think they had L2L back then. Up close it doesn't look porous like the L2L I had applied to build up the pistons for my BBC.
The ragged band at the top is just a reflection from the bare aluminum. I had thought it was just worn that way, but upon re-inspection, I think it was taped off.
The ring area is coated with something that resembles anodizing but the crown is untreated. It shows quite a few small damage 'peck marks', but some appear to be from a Rockwell hardness tester indenter, which is used to determine the maximum temperature the metal has reached.
Felix, qui potuit rerum cognscere causas.

Happy is he who can discover the cause of things.
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Re: DETONATION

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MadBill wrote: Sat May 19, 2018 5:38 pm
redliner wrote: Sat May 19, 2018 8:57 am... I cannot get pics to show up here but maybe I can take some pictures of them and send them to someones email who would be willing to look at them? THANKS!
When you're typing a reply, there is box with four bars to the right of the word "Options" below the reply box.
Click on it and the word "Attachments" appears.
Click on that and a box labelled "Add files" appears.
Click on it and it will take you to your computer's picture file or something similar.
Click on the image/images you want and then click the 'open' box.
The pic's title will appear in a box below the reply box.
Click on the "Place inline" tab and it should appear in your reply box.
(I've attached a random pic to verify these steps.)
Piece of cake, eh? :shock: :lol:
.
.

NASCAR Piston 003.JPG
By Jove I think Ive got it Thanks!
YABABBBBBY.jpg
You do not have the required permissions to view the files attached to this post.
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Re: DETONATION

Post by Scotthatch »

redliner wrote: Sun May 20, 2018 1:59 pm
MadBill wrote: Sat May 19, 2018 5:38 pm
redliner wrote: Sat May 19, 2018 8:57 am... I cannot get pics to show up here but maybe I can take some pictures of them and send them to someones email who would be willing to look at them? THANKS!
When you're typing a reply, there is box with four bars to the right of the word "Options" below the reply box.
Click on it and the word "Attachments" appears.
Click on that and a box labelled "Add files" appears.
Click on it and it will take you to your computer's picture file or something similar.
Click on the image/images you want and then click the 'open' box.
The pic's title will appear in a box below the reply box.
Click on the "Place inline" tab and it should appear in your reply box.
(I've attached a random pic to verify these steps.)
Piece of cake, eh? :shock: :lol:
.
.

NASCAR Piston 003.JPG
By Jove I think Ive got it Thanks!YABABBBBBY.jpg
Plug is a little hard to read at this distance ... can we get a close up? :shock:
redliner
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Re: DETONATION

Post by redliner »

Scotthatch wrote: Sun May 20, 2018 2:46 pm
redliner wrote: Sun May 20, 2018 1:59 pm
MadBill wrote: Sat May 19, 2018 5:38 pm

When you're typing a reply, there is box with four bars to the right of the word "Options" below the reply box.
Click on it and the word "Attachments" appears.
Click on that and a box labelled "Add files" appears.
Click on it and it will take you to your computer's picture file or something similar.
Click on the image/images you want and then click the 'open' box.
The pic's title will appear in a box below the reply box.
Click on the "Place inline" tab and it should appear in your reply box.
(I've attached a random pic to verify these steps.)
Piece of cake, eh? :shock: :lol:
.
.

NASCAR Piston 003.JPG
By Jove I think Ive got it Thanks!YABABBBBBY.jpg
Plug is a little hard to read at this distance ... can we get a close up? :shock:
BWWWAAAHAAHAA!!! Thanks but I have it under control...
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Re: DETONATION

Post by af2 »

redliner wrote: Sun May 20, 2018 3:31 pm
Scotthatch wrote: Sun May 20, 2018 2:46 pm
redliner wrote: Sun May 20, 2018 1:59 pm

By Jove I think Ive got it Thanks!YABABBBBBY.jpg
Plug is a little hard to read at this distance ... can we get a close up? :shock:
BWWWAAAHAAHAA!!! Thanks but I have it under control...
Love your car! Nostalgia racing is all we do!
eaglefield.jpg
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redliner
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Re: DETONATION

Post by redliner »

af2 wrote: Sun May 20, 2018 3:46 pm
redliner wrote: Sun May 20, 2018 3:31 pm
Scotthatch wrote: Sun May 20, 2018 2:46 pm

Plug is a little hard to read at this distance ... can we get a close up? :shock:
BWWWAAAHAAHAA!!! Thanks but I have it under control...
Love your car! Nostalgia racing is all we do!
eaglefield.jpg
Thanks man! This is my street car! 10.38@ 129+ on second shakedown of new 414/ TKO 600 combo. Yer Willys looks BADASS! How fast? What combo?
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