Still chasing the rabbit

[Paul Clark]

The article by Razor has helped a bunch, and maybe I'm just looking for a magic cure here.
Today I got KR of 18.8 with 02s at 847.
I was over 40 mph in OD, so the tranny kicked down when the sirens went off. The cool weather shot the boost up to 19-20 lbs.. I got out of it fast.
The car has been up on the hoist and checked out. Motor mounts, exhaust, etc. are okay. Tranny mount is new. Blue dial was at 2:00.
SM readings are right on. New AC knock sensor (torqued correctly) and AC 02 sensor.
Is there a chance that changing the turn-on point of the alky might help?
I don't want to mess with it unless you folks think it would be beneficial.
Thanks

 

[QUIP'6']

The article by Razor has helped a bunch, and maybe I'm just looking for a magic cure here.
Today I got KR of 18.8 with 02s at 847.
I was over 40 mph in OD, so the tranny kicked down when the sirens went off. The cool weather shot the boost up to 19-20 lbs.. I got out of it fast.
The car has been up on the hoist and checked out. Motor mounts, exhaust, etc. are okay. Tranny mount is new. Blue dial was at 2:00.
SM readings are right on. New AC knock sensor (torqued correctly) and AC 02 sensor.
Is there a chance that changing the turn-on point of the alky might help?
I don't want to mess with it unless you folks think it would be beneficial.
Thanks

847 seems rich for alky should be around 750 maybe rich knock. With alky there shouldnt be and knock at 19 psi i'm sure julio will chime in from his crazy schedule!!!

 

[Razor]

If your chasing a knock issue, you cannot let the transmission shift/downshift.

A lot of chips will have a feature called knock ignore for this reason.

Mid 800's for o2's is fine when you initially stab the gas.

Place car in MANUAL 2nd.. roll into the gas watching the boost come up and knock reading.. once the rpm's hit 4500-5000 shift into "D"

Punching the car at 40 MPH and having it downshift, a lot of these cars will show knock on the scanmaster. My old TTA would show 40 degree's knock at 38 MPH.. shifting from 1-2. Chip had knock ignore installed up to 45 MPH.. problem gone zero knock 28 PSI. No amount of anything could repair the issue unless I dropped line pressure on the tranny.. and I chose to let it ride that way and not have premature issues.

So.. place the car into a physical gear.. and roll into the throttle. Not mash it. If it passes this test, next is mash it and ignore the knock readings.

 

[Paul Clark]

This is where I get confused.

"So.. place the car into a physical gear.. and roll into the throttle. Not mash it. If it passes this test, next is mash it and ignore the knock readings."

The computer controls the knock guage/buzzer, correct? So the computer must think that there is knock in order for the gauge to light up and the siren to go off. When the computer senses knock, it retards timing. Doesn't this happen whether the knock is real or false? So there goes performance.
It seems as if it's like a smoke alarm where you sometimes say "just ignore it" and other times yell "get out of the house, now!"
I'm not sure I'm going to be able to tell the difference.
Thanks

 

[Razor]

There is real knock, there is false knock.

Real knock is your REAL worry. But when performing tests.. you need to do things trying to ascertain if real or false.

Just like hitting the engine with a hammer, that would be false knock. But your trying to tune your alcohol injection in.. the alcohol injection cannot fix a busted torque converter, broken engine mount, downpipe hitting frame, etc... So when you dial the car in.. you do things that dont aggravate the engine rocking back and forth inducing possible false knock.

This is why you roll into the throttle, watch your needle go up in boost.. if no knock is picked up.. then you have the proper amount of alcohol mixing in with your gas.

Once it passes this test.. then you start to work on WHY it knocks when you stab the throttle. And make decisions to cure the ailment.

Place the horse in front of the carriage easily.. or it will kick ya hard everytime.

If you cannot figure your false knock issue, get with your chip guy and have him add knock ignore to your chip.. this is a last resort, but available. So the knock readings are disabled for 1 second for example when you stab the gas.