Stock VT LS1 pinging

[shucks]

OK, first post,

Picked up a VTII SS a few months ago, it's stock except for a catback, tidy with good service history, mature owner yada dada. I bought HP Tuners to do some logging and tuning - was planning to start with the VZ LS1 timing and fuel tables and work from there (I enjoy tinkering with my cars). Currently running the bog stock VT tune though, and it has audible ping and a couple degrees knock retard at WOT - usually around the 4000-5000 rpm region.

Fuel filter is fresh and I'm seeing 930-970 mv on the narrowband O2 sensors at WOT so it has plenty of fuel. Running BP Ultimate and have tried a couple of different servos, and it's COLD here at the moment! Spark plugs and leads are new too, the stock MAF is clean and unmolested, and long term fuel trims are within 5%. Runs perfectly aside from the ping, and feels very strong.

I also get ping at low rpm high load - for example at 1500 rpm 4th gear WOT it will ping despite having only ~7 degrees of ignition advance and intake air temps ~10 degrees (cold night). I don't usually do this - it's a bit brutal - but is it even possible for an engine to ping with 7 degrees timing?!

Any thoughts?

[Tryhard]

Are you using 98?,had a mate that had a similar issue. Turns out his missus filled up his beast with 91 instead of 98 and boy did it ping lol. Probably not the issue here though,wouldn't hurt to run an octane boost through your system or an injection cleaner.

[shucks]

Are you using 98?,had a mate that had a similar issue. Turns out his missus filled up his beast with 91 instead of 98 and boy did it ping lol. Probably not the issue here though,wouldn't hurt to run an octane boost through your system or an injection cleaner.

Running BP Ultimate. I'll try the injector cleaner and maybe a catch can for the PCV system, it doesn't seem to burn oil but does have some oil in the intake. Might just be carboned up a bit.

[macca_779]

Pull a plug and have a look to see. Might be lean or really carbon'd up because there is no way a stock vt would ping off a standard tune as they have bigger all timing in them

[Peter B - CV8]

Running BP Ultimate. I'll try the injector cleaner and maybe a catch can for the PCV system, it doesn't seem to burn oil but does have some oil in the intake. Might just be carboned up a bit.

If it's been babied for most of its life - then it's probably carboned up a bit. Try running some upper cylinder/head cleaner through it & see how it responds. Sometimes a good "Italian tune" helps....

[shucks]

Update to this:
Found a fair bit of oil in the PCV line, so replaced the valve and fitted a catch can. Ran a can of Nulon foaming intake cleaner though, chucked a bottle of injector cleaner in the tank, set the power enrichment tables for a filthy rich 11.5:1 afr and gave it a good "italian tune-up"... and the ping has gone. I think it was sucking oil through the PCV and carboning up - short trips around town in cold weather don't help.

I've loaded in the VZ LS1 timing tables now and it's running nicely with no ping. Still running filthy rich power enrichment settings untill I get a wideband, but it goes hard now.