So I'm trying to search out if my original tune with my 192* stat is affecting my rich idle conditions,because i switched to a 180* later. Both O2's have been replaced and I have "NO CODES" in either KOEO/KOER modes. Idles great, runs strong etc, no stalling, no issues nothing, just rich at idle. Current mods: GT40p heads milled/ported - 30/1000, Cobra intake ported/milled, 65mm TB Ecam, 1.6 rollers, underdrive pulleys, electric fan, o/r/h pipe Msd distributor, Msd coil, 104 plugs new, new 255lph fp, 19lb injectors, Adj Fuel P/R at 38psi custom chip and it threw down 280rwhp_318rwtq (chip timing is set at 10* until 70% pedal depressed) ...so I've been using 93 octane and was thinking that I wasn't getting a clean burn because of the 10* at idle. So i went to 90 octane and nothing changed at idle except it raised it slightly because it's reacting to my higher compression and it's more sensitive to combustion etc. I get some slight pinging up high on the RPM's when I get into it, but normal driving I have no issues with that octane. side note: still have stock Alternator in, so my charging system is probably lower than expected with the electric fan, but that wouldn't make the fuel pump demand more, it should be less right?? Fuel pressure holds strong after engine cut off for a good 40min, no slow drop in psi until 8-10 min later. I feel like my options are limited with the no codes, what do you think about these?? a) replace ECT coolant sensor to a more newer, sensitive one. b) add a aftermarket 6al or crane mult-spark ignition c) change the stat back to 190* .....any other ideas????