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Discussion Starter · #1 ·
Made two passes on brand-new -10 plugs the other night. Will try to take a picture, probably have to cut open the plug to get a good shot. Timing mark was right before the bend. Fuel ring was on the dark brown side, about .060 up the porcelain. To me and my buddy it looked perfect.

So here's the question: If this was a -10 plug on a .063N jet on top of a 600hp 14.8:1 motor, what happens when I try to go to a 200hp shot later? Do I need to remove even more timing and/or go to a -11 plug? What is colder than a -11? I'm a little shit compared to a lot of people here. What are they running for plugs? Or do they simply pull a ton of timing out to keep things cool enough in the chamber? How much cooler do the other fuels run, or do they? I currently use Sunoco 112 (Blue). Would Red cool things any better? We have C16 at our track and I think they have one of the VP NOS fuels, don't know which one. If those other fuels won't run cooler and let me run more timing than I won't bother trying them. I have no detonation problems with what I am (or have) been doing...........

Been learning without burning thanks to all of you on this site so far, THANKS! Hope to keep my pistons outta that sticky up above!
 

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Discussion Starter · #5 ·
So the higher octane fuels simply help prevent detonation because of their resistance to burn (to put it simplistically). They do not lower the temperature in the chamber itself.

The more power you make the more heat you make and therefore you need to keep the chamber below a certain temperature otherwise our alumimum pistons simply be gobs of junk, right? Doesn't matter how the power is being made, turbo, blower, nitrous, or N/A, right?

Then what do the guys do with heads like the LS2's and SB 2.2's that only run 20 some degrees normally? Can they actually wind up running at TDC? (no advance at all?) Can they possibly run ATDC? That doesn't seem right. But if they make 800hp on motor and try to throw 2 or 3 kits on it how do they control the temps in the chamber? Can't only be timing........

I'm not in that boat, only trying to learn as much as I can.

My plugs looked great, I'll try to get some pictures. Maybe I will cut one apart again, that's always fun with my rotozip!

Tony: If you were able to run 9.0 or better on Sunoco Purple, that is nutz! I ran C16 on my other motor to be safe. Found out later that it wasn't 15:1, only 13.2:1, Purple would have been fine on it!
 

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Discussion Starter · #6 ·
Ok, here are some pictures of a plug. Car ran perfect. All the plugs looked like this one so I didn't cut them all apart. Kinda hard to see the timing mark but it is there right before the bend. So tell me what you think of the fuel ring. I plan on leaving it basically as-is. If I was to pull more fuel out I would have to pull timing also, but I was happy with the way it ran on this jet.



 

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Discussion Starter · #14 ·
Yes, but that sticky died over a year ago, all the pictures are gone.

I plan on making a few more passes with this tune but with a little less fuel and timing. I am running a dry EFI system so I have to experiment with adding/subtracting % of fuel (either add or subtract from the main fuel curve).

I thought the plugs looked close but possibly still on the rich side (but certainly not too fat). On motor I run my A/F around 13.0. On this nitrous pass it was 12.1 A/F (using an LM-1 from Innovate)

What will using a higer octane fuel do for heat in the chamber? Will it cool it at all or should I just pull more timing?
 
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