LIL SS

iTrader: (9)

Here is a A-tap spreadsheet to look at: KR Problems

You will find that there are major KR issues. He has put 100 octane in the car and the KR doesn't go down at all. I think that something is hitting somewhere. These are some of the things that have been checked (I'm sure he might chime in here):


Headers Hitting Front A-arm mount and frame. The Passanger Kooks header is very close to this area. He has taken a grinder to the area to try and make room for motor flex. He has also put some header wrap in between to try and reduce the hard knock if it is hitting there.


Driver Y-pipe was hitting at one time and this has been pulled down and no longer hits.


A-tap shows good on O2's and with 100 octane..




What else to look for? I think it is hitting somewhere as the KR spikes when it is nailed and drops off. Any ideas?


Car in question is a 348 / A4 / full bolt ons / heads / cam..

HumpinSS

iTrader: (1)

I have the same problem I am trying to diagnose. I found some bent pushrods from a mechanical over-rev and i am pretty sure i am experiencing valve float, so the next thing i am swapping out is the springs. I feel they have gotten weak and are allowing the valve to slam on the seats making the computer think its detonation thus backing off the timing. My logs look very similar and the only thing that is left to check and replace are the springs.

foff667

iTrader: (2)

What year car is it that were speaking of? I find it odd that even under slight load 30/40%TPS it still gets like 3 degrees at some points just at 2000rpms cruising...id assume something hitting or your knock sensors are just bad...i know in my 98 ive had to deal with false knock for the past 2 months ive had it...ill probably get a couple of new ones once i change the heads/intake. not much you can do other then desensitize them...i think the newest version of ls1 edit will allow for this.

lata
Bill

Reboot

iTrader: (5)

By chance is your friend running a double timing chain? I heard these tend to cause false knock.

SNAXS

I was battling KR for a long time and I just gave up and turned off my Knock Senors. That did away with teh problem and gave me the times I wanted to see.

DanZ28

iTrader: (5)

Shaun, thanks for posting this up for me!

Car is a 00' year!

Don (Reboot), this is Dan (AKA GR8WHITE), I took off the double roller in favor of the Jwis replacement chain back when I first put the motor together because of the ASP pulley hitting it.

I thought about it being valve float, but the KR will spike at WOT even at lower RPM's and yes there does seem to to be some KR at random on lower RPM's. I think I would even see more if A-tap wasn't so slow at reading data. The push rods are straight and I have some new AS heads with 987's.

Well, I can't say if the sensor's are bad, all I can say is I didn't have any knock with these sensors on the old motor. It's possible something is still hitting, but I think I've done everything I can to eliminate this.

How do you turn off your knock sensors? edit?

Thanks for the help guys, keep it coming!!

Dan

SNAXS

Yes with edit

niphilli

Could also be a poorly balanced crank pulley (if you have replaced it with aftermarket or if the stocker was damaged).

LIL SS

iTrader: (9)

The crank pulley is the same on he was using with the old motor.

Any other ideas?

VTtransam

You seem to have the same problem that I am having. Do not edit out your knock sensors! Replace them if anything. Like Nick said above, I think my problem may be with the ASP crank pulley. I'm going to put the stocker back on and see if it helps. You might want to try the same thing, I've heard some of the ASP pullies can cause false knock.

Matt

LIL SS

iTrader: (9)

There was no KR on the old motor that was using the same pulley. The pulley hasn't been dropped or damaged. It is not the pulley..

Since the last motor there have been minor changes to the boltons which include: Kooks headers and y-pipe, different verter and I think that is it.