getting KR

[07extgraystone]

alright I have 07 silverado with 5.3l I am running version 8r10 I have the diablo tune installed and running 87 octane. I have the timing bumped down 10 clicks and I am still getting KR at WOT.. can anyone explain this? the timing is almost in stock location on the programmer, it might be 2 clicks advanced. what should I do? put the 87 tune in? need some help.... oh yeah if it matters I have magnaflow exhaust and volant cold air..

[06MonteSS]

yeah, you need to put the 87 tune in.. the diablo tune is for 91/93 octane... and bumping down the timing by 2* isn't gonna do much, since the diablo tune also has a more aggressive air/fuel mapping as well. if you want to run the diablo tune for most performance, then you must run 91/93 octane gas..

otherwise, you need to install the 87 tune.

[07extgraystone]

so what has diablo changed in the diablo tune to cause KR other than timing? I have bumped timing down 10* or % whatever it is measured in on the tool. I am pretty much where the timing is stock maybe 2* advanced from stock. I filled up with 89 tonight and will check tomorrow for KR. thanks for the help

[06MonteSS]

YOU NEED TO USE THE 87 TUNE FOR 87/89 OCTANE GAS!

-10% on spark advance is only equal to about 2*... not enough to do anything to the diablo/performance tune, since the spark advance is advanced more than 2* from stock.

either switch tunes, or switch gas.

also make sure you're using Mobil, Exxon, Sunoco or Amoco brand gas....