Close call with detonation today

[skidad62]

Last day before I put my 03 Centennial Edition GT away for the winter... and I ALMOST blew my motor!!!

I'm running a Vortech V2SQ - SI trim, 42 lb injectors, twin SVT 255 lph Fuel pumps and dual hotwiring to the pumps, Procharger intercooled, 3.12" vortech pulley, AFM powerpipe, and a 95mm Sniper MAF... Running 91 octane (highest we can get here) and a conservative tune.

I was on my way to the gas station to add fuel stabilizer and fill up... and decided to give her a rip down an on ramp and onto the highway... I had less than 1/4 of a tank... BIG MISTAKE!!

My twin 255s weren't getting enough gas under hard accelleration at WOT and she went lean and detonated.

I limped back to my tuner who removed the plugs - 6 of the 8 plugs had melted the tip off!! We put a videoscope down all 8 cylinders and all is clear inside - no piston damage.

A fresh set of NGK TR6's and a full tank of gas and all is well. I was some relieved she came back to life with no permanent damage.

Man I am lucky that didn't end VERY badly.

From now on - I will consider 1/4 of a tank as bone empty - I do not want to ever go lean like that again.

[LS1killer]

same thing happened to me two weeks ago besides mine happened a little different and I had enough gas in tank. scary. good thing its ok. do a compression check? do you have the cobra tank or stock gt tank? 1/4 empty is too low. Im using the halfway mark as the cutoff point for me now after I saw a few datalogs of running it at 1/4 tank

[Invictus]

Get the 03/04 cobra fuel tank and problem solved.

[2003GTIZZLE]

It is funny because I was about to rip on the car yesterday and saw the guage and was like nooooo I better get gas first. I have a stock GT tank with a focus pump and 60lb injectors with a safe tune. Filled her up and then went for a rip. I am so used to trying to keep my old NA setup nice and light, now I have to tow a trailer of fuel behind me to feed the little angry 4.6 HA!

JTR

[meaty mac]

Originally Posted by skidad62

6 of the 8 plugs had melted the tip off!! We put a videoscope down all 8 cylinders and all is clear inside - no piston damage.

Would that actually show the entire condition of the ring lands? If you torched 6 out of 8 plugs, and you didn't do ANY damage (from the top ring up) to at least one piston, then you are lucky

Originally Posted by LS1killer

do a compression check?

Might not be a bad idea.

[CDR Stang]

After you start driving it again, scope the cylinder walls for scoring. A fractured ring land (between comp rings) could still be present, just not apparent now.

[skidad62]

Yeah... it's in winter storage now - will run a leakdown test to check valves and rings to be sure. Fingers crossed.