I should have known better than to ask. I just figured since there were a bunch of people here talking about it, I might as well ask. But thanks, I now have a full understanding of the knock circuit. It just clicked all of a sudden, at least I hope it did.

 

And you want to talk about costing hp. I unplugged my knock sensor at the track and went from 14.1 to 14.9.

 

So let me get this straight. So because you unplugged it it defaulted to protect the engine since it detected something wrong with the sensor? At that point it wasnt just pulling timing it went into a Knock protect mode? Am I even close?

 

Instead of basing knock retard on the signal being received from the sensor, it started using a knock retard that was based on a calcualton or table, as a function of other engine operating parameters. That knock retard will show up on a scanner as exacly that - knock retard - whether its caused by the signal from a functional knock sensor, or caused by a protective default as a result of a non-working sensor.

I run my engine with an aftermarket ECU. I have no knock sensor. But my factory PCM is still connected, and running some things like idle air control, speedometer and emisions devices (well, it used to). I have a full-time readout on the stock PCM, and it shows knock retard values in the range of 3-12deg depending on how the engine is operating. It shows 3deg of knock retard at idle. Of course it has no affect on the engine, because the stock PCM is not controlling the fuel or timing.

 

Why not set the knock retard values to zero since your computer cant do anything with it anyways?

 

Lets say that I corrected my knock sensor circuit problem or whatever... If I am getting 3-12* of knock retard, that is normal? Wouldn't I get more power if I had 0* of knock retard all throughout the rpm range? Is it possible to get 0*?

 

I'm not sure if anyone can be zero all the time unless everything from the tune to the engine itself is perfect. A friend mentioned to me before that the computer sometimes retards timeing between shifts. I know my 97GT did to protect the tranny I guess but I had it tuned out. Is this the case also with the Camaro?

 

What are the chances that I would even detonate in the first place? Is detonation a risk you have to run to go fast?

 

I think it's a risk that can be minamized through proper tuning and a mechaniclly sound motor. I guess when you look at it youre constantly at risk. You never know when youll fill up with bad gas or have a engine problem I guess so youre always going to be at risk wether youre trying to be fast or daily commuting to work.

 

It's not really a risk but it is a chance you take. If you run 91+ octane all the time you should be 99% in the clear. I've mostly heard of detonation when people use nitrous with a low octane gas. So unless you're running nitrous you don't really have anything too much to worry about.

 

What is a normal amount of knock retard to be getting with the works (full bolt-ons, huge cam, solid roller or roller rockers, longtubes, bullet mufflers, etc.)?

 

any knock above 3 degrees isn't too good cause you're gonna start to lose horsepower. If you're in the 1-3 range of knock retard i wouldn't worry about it.

 

No.... "0" is "normal". If everything is set up properly, you shouldn't see much in the way of knock retard at all. You do get it sometimes at WOT with lifting throttle shifts, at least from my experience. But the goal is to continue to put in timing, as long as its increasing power output, and to put in just enough to put it near the point where its going to start showing signs of detonation. How much cushion you put in depends on how sure you are that you will always have the exact same quality fuel, and how sensitive your engine is to changes in inlet air temperature, coolant temperature, altitude, and other things that can affect the tendancy to detonate.

If you correct the DTC 43, you should no longer get 3-12deg KR.

Why change anything.... I get codes for:
-no MAF (its been deleted)
-no knock sensor (its been deleted)
-all the A4 codes (had to swap thwe M6 program to an A4 program to get the correct speedo reading out of the TH400 VSS)
-no injectors (there connected to the MoTec)
-no ICM continuity (don't use the stock ignition system)
-all the AC codes (AC deleted)

The PCM is basically a hollow shell that still runs:
-VSS
-IAC
-fuel pump
-fans

 

Just do the resistor trick. Reset your PCM. Then take for a spin. It is $2 take maybe 10 minutes or less. Well worth it.

 

but if your circuit is in fine working condition and you're getting any retard, that means you have a problem that needs to be corrected, right?

Even with longtubes, roller rockers, and a huge cam, i can still get 0* of knock retard?