PLX Wideband.Chrispy wrote:Thanks for posting, unless you are measuring with a wideband I wouldn't reference the stock PCM readings. Did you raise the rev limit when you raised the shiftpoints? They both need to go up in the stock tune.
No... I didn't raise the rev limiter when I did raised shift points with the "modify stock tune". I didn't know that. and it gave the warning that the rev limiter would be raised. At least I think that's what it said. I didn't really read it carefully since I've seen it so many times raising shift points on the performance tunes. Did it say something like "You NEED to raise the rev limiter"? instead of the message that the rev limiter WILL be raised? I'm running 8r20. Definitely hit the rev limiter pretty hard though
and that would explain it. Still bumped it after reverting to Original Backup (unmarried and everything). Oh well... no drag racing when I'm on the way to the dealer for service.You lucky guy. Who knows what we're getting here in the CA Bay Area. I've switched from Chevron to Arco and had my first 1/4 mile with zero knock. Whoo hoo! but who knows what was the cause of that since a number of things were changed/different. More on that below. Searching on the net for BP, Mobil, etc. gas stations here (I know we used to have BP but it may be Arco now) and found out the following when reading about Mobil coming back to the Bay Area. CA regulates the gas coming out of the refineries in the state so they are all supposed to be the same. Who knows how consistent that is or what in the world the requirements are... The same fine eco nuts that forced MTB on us. Anyway, like in Mobil's case, the nearest Mobil/Exxon refinery is in Torance and delivery wouldn't be practical. So the state allows gas stations to get their fuel from any/other companies refinery. Bay Area Mobil stations might get their gas from a Shell refinery and then they add their additives package as it goes in the truck. Arco is owned by BP and the literaterature says they are regularly sampled by BP to meet BP requirements. Whatever that means. I'm hoping it means it's essentially the same gas. They say their methanol like/type oxyginate helps to reduce knock.I'm thinking there is a fair bit of correction going on after several drives in various load/throttle conditions. I'm going to drive mine for a couple of days and log again. I found out that 91 shell gas up here in Canada is not oxygenated so I'm running a tank of that and will test on the 91 Perf tune. I've added 3% fuel to all ranges to account for the HF cats and will see how it works in the coming days.
I was still getting a couple of bumps of up to 2* KnR. Only in 3rd gear. Bump at about 4400 to 4600 tapering off to about 5300 where it would bump and taper off again. At about 5600 to 5700 it was zero again. So I added 2% more fuel in the mid range and 1% more in the upper range and bingo. I'm not really sure how much I've added total (probably around 5% to 7%) but it doesn't really matter since I'm using a wideband. I initially tried 12.5 across the range, then 12.2 across the range, and now it's pretty much 12.2 in the low rpm range and 12.1-12.0 in the mid and high range. Overall I think I've pulled about 5* of timing... Spark advance is running from as low as 15*, usually 16* or 17* and very occassionally 18*. Not good at all but maybe not horrible. So next thing I'll try is adding 1* in all ranges and see if the KnR comes back, rinse, repeat if the gas is making a difference. Like I said, I pretty much just ran all the Chevron out (3 partial fills totalling about a tank and a quarter so it was getting mixed a bit), outside was a little warmer, and I had just added more fuel. Here's hoping...
so I put my .02 in this post 
