Camaro ChriSS

I've been working on my tune and I find I get KR (about 3-4 degrees) only in 3rd gear (A4 4400-5200 rpm, so at 90 mph+). There is no issue at all for 1st or 2nd gear. The KR drops as the rpms rise. Seems to be around o.80 to 0.84 g/c.

Just wondering about why 3rd gear only? Would it be that its where the engine has the most strain with air and road (friction) resistance - having to pull harder than in 1st or 2nd?

Or would it be something else?

dynocar

"Just wondering about why 3rd gear only? Would it be that its where the engine has the most strain with air and road (friction) resistance - having to pull harder than in 1st or 2nd?"

You answered your own question correctly.

Camaro ChriSS

Yeah, I was just thinking out loud about it and wondering if that was the likely answer. Just wondering if the consensus has found the same thing?

Thanks for replying dynocar.

God Forgives I Dont

Well not sure if this is segnificant or not, but... 3rd gear is the 1 to 1 gear for the A4 tranny. I have a problem with mine were in third gear I get a lot of vibrations that I don't get in any other gear. I posted about it and the only awnser I got back was that our stock torque converters sometimes have an issue internally and will try to tear themselves up. Now I don't get any KR specifically in 3rd gear but who knows.

SmokingWS6

iTrader: (1)

I bet its reading a higher load in 3rd gear. On my histogram sometimes it'll drop a cell on the timing chart in 3rd gear when I use to get knock. I dropped timing a few degrees in thoes areas however i still get some from time to time. KR usually lessens as the rpm's rise due to the afr curve. gets richer as the rpm's rise.

Camaro ChriSS

One thing I can't figure out is how to precisely remove timing in 3rd gear (using edit). From what my data logging has shown so far, my g/c is the same for 2nd gear as it is for 3rd at the same rpm, hence removing timing for just after the 3rd gear shift does the same for 2nd gear shift as well (which I was trying to leave alone).

Not a big deal, but it would be nice to be able to remove the timing just in 3rd. Is that possible with Edit?

God Forgives I Dont

I think your right and there is no way to remove timing in one gear as apposed to anouther. But I'm no expert though so take my statements with a grain of salt.

Camaro ChriSS

Yeah. I would have thought that the g/cyl would be different through each gear at WOT, but it doesn't appear so from my data logs. For me, WOT from 4400-6400 rpm settles in at 0.82-0.88 gm/cyl through all gears, being higher at low rpm only. So it doesn't seem that you can affect just one gear that easily.