I couldn't wait for my wideband. Figure the canned tunes aught to be relatively safe but I'm not thrilled at my logs. I'm not really worried but not thrilled either. I think they added more fuel to r20. I haven't really driven very far with it either -- 100 miles or so. Naturally, puttering around it looks about the same. I did 3 quarter mile runs yesterday. Pretty much back to back. 1/4 mile, 1/2 mile or so to next exit, turn around 1 mile back and run it again... Knock retard was a bit different between the 3 runs but still constant more than zero. Running around normall and with the stock tune you'll see momentary knock retard up to maybe 5. Usually right after a shift. With the tune at WOT it's hanging around 5 or so through the run. Should I expect it to drop to zero in the middle of the rpm curve? Here's the 3 run graphs in the order that I did them. The cursor bar is at the peak kr value for that run. Any thoughts?
BUMP (17 views dammit, no thoughts) Haha, you can see the reason for the times... First run was the best 'cause I just sort of eased out really slow and only broke traction a little on the 1-2 shift. Second run I was too aggressive taking off and expected it to hook up after a bit like it used to ... but it didn't and I had to lift. Same thing happened after the 1-2 shift (but it never used to do that). Third run wasn't quite so bad on the launch and it just didn't seem that bad on the 1-2 shift (but the graph says it was). It was like the back end was wiggling back and forth just a little bit... for a long time. Felt like the suspension was real loose. I kept thinking it was right on the edge ('cause it felt that way) and that it was going to hook just any instant so I didn't feather it ... and it didn't hook. lol. Any way, I'm interested in the knock retard. It seems to have gotten better each run. I think I've driven plenty closed loop for the long term adaptives to have adjusted to the tune and running WOT doesn't change them.
only saw 7 on the first run. I drove it down to Laguna Seca Fri. Basically highway crusing. Golf today (I won!) and now we got to wait for this freak storm before I can get back to my "track".
Hmm keep an eye on it. May need to add a bit of fuel. Let me know. I saw upto 5-6 with Sunoco 94 on the 93cai tune with R16a...which I still run. Anyways, hrs on the dyno brought me back and made power, but especially torque. I will be putting th car back on the road in 1 week from today!!! Niice you bastards golfed today!?!?! bah!
I have an 08 GCSRT8 with 91 CAI Tune..Data logged via predator and I am seeing -.05...-2.0 KR from around 4400-5300 RPM...No KR during shifts...
I see nothing really abnormal. If you have more than just a CAI and a cat-back you will need fuel added to bring down your a/f's back to where they are supposed to be in the low to mid 12's (which if this is the case would also cause less knock retard to take place). Assuming your a/f is correct, these knock retards appear normal for the Diablo canned tunes which run fairly high timing. Knock retard will change on every run since the engine's operating temps are changing with every wot run, and the higher the gear, the more KR you will see, too. What mods are you running? What was the ambient temp when you recorded these? Joshua, HHP
Thanks Joshua. aFe II CAI, Mopar cat back, 180* T-stat. Ambient was about 60* maybe a couple of degrees cooler. I was just assuming (for no particular reason) that I'd see kind of the same KR as the stock tune -- maybe a bit up to 5 or 6 right after shifts with zero through the mid and high rpms. Sounds like I should expect a bit anywhere at wot. I'm also under the impression that as you get up over 6 or so it's more of a concern? and something over like 9 or 10 is a big concern? (even momentary maybe?).
5 or more degrees KR would definately be too much... at least for me, most of the time. There are times where (depending on your tune and weather) you may see some instantaneous "high" KR at shiftpoints since manifold pressure instantaneously drops for a split second but I wouldn't myself leave a KR of 5 or more in there. You'll probably get more power pulling timing out if it's that high. If you have close to 10 degrees of knock retard on a canned Diablo tune with just basic mods then there's something wrong. Either you're too lean or you could have a bad knock sensor or something else far worse (damaged engine) could be at play. Joshua, HHP
Ok. I have never seen more than one instantaneous 7 KR and mostly peaks of 6 after a shift and under 5, trending towards 0, on up the rpm curve. For kicks I think I'll try pulling about 5* in the 4000-4800 range and see what that does. I'll be going for an oil change/service probably next week and I'll see if I can have them weld bungs in for the wideband. Thanks for your thoughts.
