odd looking spark plugs

[Jim Comet]

Hey guys, these plugs are out of my 416FE. This is after dyno time and 38 drag strip passes on a brand new motor. The last 15 passes were running 28deg timing to slow the car down to run in the 11.00 index class. Can race gas make these deposits? The car has idle time on these plugs before pulling them. The motor is running great, I just haven't seen deposits like this before. Jim
Motor specs:
416ci
12.4 to 1 comp.
Edelbrock heads
open headers.
VP110 fuel.

[Joe-JDC]

Are you losing water in the radiator?  Looks like moisture and rust bubbles.  Joe-JDC

[machoneman]

Ouch! Definitely water. Hope all 8 don't look like that.

[Jim Comet]

I'm not loosing anti freeze and there was no smoke on any passes. With open headers, could it be condensation in the cylinders with open exhaust valves? It has been 1 and 1/2 weeks since the motor was last started. I am running an antifreeze mix if that makes a difference. Jim

[GerryP]

Look up the MSDS on your fuel to see if it contain manganese.

[Jim Comet]

It doesn't appear to contain Manganese. Jim

[Falcon67]

Some of that looks like what you'd see with methanol if you don't fog down the motor before short term storage.  At any rate, I highly recommend fogging down an engine that will be resting for a few weeks between races.  Sta-Bil fogging oil or Klotz.

[falcongeorge]

what concerns me more is the black flecks on the porcelain on the first plug. When you are looking at them in person are they shiny and metallic looking? How much timing did you have in it before you walked it back to 28?

[machoneman]

Yeah, with open headers and layovers, it could be condensation. Yet, that's still a lot of brown stuff for sure.

Parked on gravel, stone or anything but asphalt or concrete? Parked outside, garaged, in a very humid area?

One fix would be to stuff rags, etc. into the collectors after a run or getting it home. Then see if that makes any difference.

Agree that those black flecks need investigation as well.

[Jim Comet]

It has only been a week and a half since I ran it but fogging may be needed between race weekends. It is possible that there was some detonation due to timing. The reason is, I was running an adjustable rotor. My son was making a pass and bang, pop and boom the motor quit at half track. We towed the car to the pits to investigate and what we found was the 2 screws that hold the rotor in phase came loose so the timing was off. I pointed to rotor towards number one and tightened the screws and it fired right up. We checked the timing and it was at 28deg. We decided to make a test pass and it ran 11.02 which was perfect for the 11.00 class he was running so we left it there. Every pass after that was an 10.97 to 11.06 depending on if he deep staged or not. The car ran great the rest of the weekend and my son took second place because he fouled in the final when he erred on his deep stage. I have now replaced the rotor with a standard non adjustable type. I got new plugs and will check them carefully after his first and second pass. Hopefully there is no more specking. Jim

[gt350hr]

 The top picture ( to me) shows some aluminum deep down in the crevice which would be from detonation. The black spots are possible from some small amount of oil but "to me" the biggest potential issue is what appears to be a gray deposit surrounding the electrode. That could be lead fouling or detonation as well. The rust bubbles should only be on a cylinder that has an open exhaust valve . The humidity must be very high where you are as I never see any rust bubbles on my race engine that can easily sit for a month at a time. So Cal is not known for high humidity and that may be the reason for me not seeing it.
    Randy

[Jim Comet]

I am in Minnesota, The car is parked in a closed garage on concrete. I may have to rethink my storage routine between races. I am using VP110 race fuel out of my own barrel that I keep sealed. The barrel was opened in August so it should be good fresh fuel. Jim

[Joe-JDC]

Anti-freeze in a race car?  Quick check would be to remove valve cover and see if the exhaust valve is open on that cylinder.  Joe-JDC

[Jim Comet]

Do any of you use fogging oil on your race motors between race weekends? I am not using/losing any coolant and my oil is clean and clear. I have read on some forums that leaded race fuel can leave deposits although I believe the bubbles are moisture related. Jim