67SS509

iTrader: (25)

Made some 200 shot runs yesterday on new plugs. Engine was cut off after the run each time. Could not see any fuel ring on the ceramic when I cut the threads off. The strap looked about right for timing. Also ran my FJO serial wideband at the same time so I could make a comparison. Fuel was increased untill AFR was 11.60 - 11.70 and plugs stayed clear white. The fuel I'm using is VP 109 racing unleaded. Plugs are #8 NGK's and timing was at 19*. Are these results normal for unleaded fuel?

dnkynrbk

iTrader: (34)

I have had to make 2 or 3 passes with a new set plugs then towed to pitts then change the plug and cut it. This is after you get it in the ball park first. That way there is a good line on the porcelin.

camscam02

iTrader: (21)

it should show a fuel ring

can I have more info on the setup. engine, nitrous etc.

67SS509

iTrader: (25)

It's the LS7 in my Camaro in my sig. NOS plate between throttle body and elbow. Carb style intake. Drag only car with powerglide.

Attached are pics of typical plugs with 4-5 passes and lots of idling and one showing just one pass on a new plug and no idling.

camscam02

iTrader: (21)

what was the nitrous tuneup in it?

ATVracr

iTrader: (5)

Looks a little lean to me, put a little fuel in it and see if it picks up mph.

I dont care what the 02 sensor says the plug doesnt lie.
What hole did that plug come out of? We need to see #7, #8 and any 1 of the other 6 so we have a comparison.

67SS509

iTrader: (25)

73 jet on the nitrous and a 55 on the fuel instead of 51 according to NOS. Fuel pressure is 58#. Motor is tuned n/a @ 12.7 AFR

camscam02

iTrader: (21)

based on your info and what the plug looks like I dont think the wideband is correct or something else is going on. I agree with ATV 100% on what he said.

Although that jetting and plug should show a decent ring.

67SS509

iTrader: (25)

That plug was from #5 and the 2 beside it was from 2 & 5. I tried a 59 jet but the car felt like it slowed down or at least didn't speed up. Runs are being made on the hwy so I don't have times.

Do fuel jets that big sound believable at 58#?

ATVracr

iTrader: (5)

Should be rich by the jetting ... IMO. ...... Strange !

Do all the plugs look like that?

ATVracr

iTrader: (5)

Maybe its something with that fuel? is it MS109?

67SS509

iTrader: (25)

Only cut that one. The car does not act like it's rich.

67SS509

iTrader: (25)

it is MS109

ATVracr

iTrader: (5)

Checked VP site and the MS109 is a clear oxygenated fuel.

Change to C16 and you will get a much better plug reading and its safer for nitrous.

67SS509

iTrader: (25)

I appreciate the help guys.....

ATVracr

iTrader: (5)

No problem.

We tried oxygenated fuel 2 years ago and it is tricky to tune on nitrous.
Not something I would ever try again or suggestion anyone else to try.

Good luck.

camscam02

iTrader: (21)

ohhh its oxygenated fuel. I was lost before that because everything pointed towards rich but the plug its self.

c16 and try again, I bet it has a pretty decent fuel ring and probably pretty rich.

Atv takes the cake. haha

1BADAIR

iTrader: (1)

what did you use to cut the threads off?

67SS509

iTrader: (25)

Picked up a 4" dia. carbon cut off blade from Lowes, stuck a bolt and nut thru it and used it in my battery drill. Works great and can be used anywhere.