For a '92 5.7 TPI?

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Rob
High Performance & Party page
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89 TTA #426 20th Anniversary turbo 3.8 bone stock
94 Silverado Tuned Port Injected
87 Grand National- lil' ole V6, highly modded
95 Trans Am Conv.- LT1

 

Yes.

Knock Attack Rate vs RPMs
Knock Recovery Rate vs RPMs

Tim

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TRAXION's 1990 IROC-Z
Best Time = 12.244 @ 112.51mph (1.778 60' / 7.819@88.32mph in the 1/8)
All Natural. No Force. No Drugs. Stock Bottom End. Stock Body Panels.
Gunning for NA 11's with bigger cam, bigger stall, and bigger exhaust.
-=ICON Motorsports=-
Moderator: PROM board at thirdgen.org

 

There is also a Maximum Knock Retard vs MAP and Max Knock Retard vs RPM. It is useful to also use these because I found that if you get too aggressive and put too low of an attack rate and/or too high of a recovery, you may have knock occuring but the ecm keeps removing the retard even though knock is occurring; thus making REAL knock occur.

So I found a slightly less aggressive attack/decay rate with a "cap" works better.

Also, I just found another knock retard in the "octane" routine that almost permanently retards your spark. I am still investigating this, but I found that by adjusting the "recovery amount", "maximum retard amount" and the kpa "threshold", you can make this retard recover very quickly (provided no further knock occurs).

 

Thanks for the info. I'm getting upto 15 degrees sometimes because of a rod/bearing knock and I'm trying to figure out a way to skirt the problem for a while till I can tear into it, short of removing the knock sensor all together.

 

Not to nitpic, but those have nothing to do with the actual sensitivity of the system. Just how the ecm reacts to the sensor.

In the MEFI applications they use a 45d male to female fitting adapter to dampen the K/S mounting.
On my car I have a T fitting with a early and late K/S so I can switch to various ecms.

In any serious tuning, you have to double check for detonation with plug readings

 

I found a schematic (on some other message board) that includes a series of resistors that can be installed in the line to the knock sensor. It supposedly "muffles" the signal and effectively desensitizes sensor. I don't know if it really works, but have installed it on my car.

According to my scan tool, some knock is still being detected and the timing is getting retarded by as much as 9* in some cases. No matter what changes I make to my timing tables, I can't get this to go away.

I brought this up in a post (now a thread) in the General Engine board https://www.thirdgen.org/messgboard/Forum7/HTML/005943.html. Glenn tried to help me there, but I'm stuck because I can't change those parameters on my bin with TunerCat.

At any rate, if you're interested in the schematic, let me know, and I will try to find the link to it.

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'87 IROC 5.7l TPI - original owner!


[This message has been edited by P J Moran (edited March 16, 2001).] (Fixed the link to the other board thread...)

[This message has been edited by P J Moran (edited March 16, 2001).]

 

I have never done it but you could probably use something like a 22uf(or higher) capacitor to change the wave form a little which should have some dampening capability.
-Carl

 

PJ, if you know the addresses, you grab a trial offer version of TDF Editor from TunerCat to create a "constant" or "table" within your TDF. This is how I initially added certain tables and constants to my 8D tdf when they were not defined.

In fact, I was so impressed with TDF Editor that I ended up buying, I found it so invaluable.

 

As I understand it, I need a hack in order to know the addresses. I don't have the hack for a $32B (or any other, for that matter), so again I'm stuck. I would like to get the hacks for $32B and $6E.

I have downloaded it (the TDF editor) and I'm sure I would come to the same conclusion, but it's useless to me right now.

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'87 IROC 5.7l TPI - original owner!

[This message has been edited by P J Moran (edited March 16, 2001).]

 

There are 4 generations of K/Ss that I know of, so unless your using the right generation strategy, you might generate some real problems by having toooo much of the signal detuned.

Some folks like trying to throw software cures for mechanical problems, I tend to use mechanical corrections for mechanical problems, etc

 

Are you implying that I should look at using a different sensor? If so, what would you recommend? I am using my original sensor, now.

Or are you saying that I should work on the engine tuning to solve the problem? Changing (reducing) the timing hasn't helped.


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'87 IROC 5.7l TPI - original owner!