detanation or going lean

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Nov 16, 2009 | 05:45 PM

9sectruck

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From: jefferson city MO

detanation or going lean

Nov 16, 2009 | 06:21 PM

9sectruck

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From: jefferson city MO

Nov 16, 2009 | 07:52 PM

OUTLAWZ RACING

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From: COLUMBUS GA.

Did u do the conversion to read e 85 with the afr guage? If it was 11.8 on a standard afr guage it went lean, from the pics it looks lean on top from the pistons. Plugs cant really tell the story un less you pulled them hot.

Nov 16, 2009 | 07:57 PM

98Z28CobraKiller

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From: WPB, FL

Quote:

Originally Posted by OUTLAWZ RACING

agreed. Those ring lands look melted, not just busted. Also, the fuel ring is down inside the plug. You have to cut the threads off the plug in order for us to be able to see it in a picture. And as Outlaw stated, the plugs have to be pulled right after the pass. Shut down, No idling.

Nov 16, 2009 | 08:06 PM

9sectruck

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From: jefferson city MO

my wide band is set to read gas lambo
the plugs where drove on

Nov 16, 2009 | 08:50 PM

98Z28CobraKiller

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From: WPB, FL

How did the rest of the piston tops look?

Nov 16, 2009 | 10:18 PM

Johnv

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From: New Zealand

I would think that with E85 and 3 x 14gal/hr meth nozels,
11.5 AFR is way lean !!

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Nov 17, 2009 | 10:10 AM

9sectruck

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From: jefferson city MO

here is a pic of a good piston the 5 good ones look just like
http://i788.photobucket.com/albums/y...pistons001.jpg
http://i788.photobucket.com/albums/y...pistons002.jpg

Nov 17, 2009 | 10:50 AM

#10

hellbents10

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From: Spring Lake, MI

11.5 is not bad on gas scale, the amount of ignition advance you are running depends on a few other factors though. compression, cam, cylinder heads, and the inlet air temp (which should be OK with the amount of meth and ethanol). Did you verify that there was 85 eth in the batch of E85 you put in the car? If it was down to 70% or so then you would not have the octane you need, although you would be richer on the AFR gauge.

looks like more of a distribution or injector problem though.

Nov 17, 2009 | 11:13 AM

#11

98Z28CobraKiller

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From: WPB, FL

Quote:

Originally Posted by hellbents10

Did you verify that there was 85 eth in the batch of E85 you put in the car? If it was down to 70% or so then you would not have the octane you need, although you would be richer on the AFR gauge.

How do you verify the % of ethanol?

Nov 17, 2009 | 11:25 AM

#12

HUNTER02SS

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From: Kennesaw, Georgia

Also, you need to get rid of those projected tip spark plugs. Boosted engines are supposed to run non-projected tip plugs. TR6 plugs are projected, but usually don't run over 700hp. Anything more go to non-projected.
If you like the autolite plugs, use the AR3934 plugs. These are non-projected.
EDIT: I also think 28deg. of timimng is alot for 17 psi. I would back it down to 20deg. as well.

Nov 17, 2009 | 12:10 PM

#13

Chevy406

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From: Huntsville, AL

Just how deep are the valve notches? While they didn't cause the problem, it certainly made for a weak point in the piston for when it went lean.

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