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Mar 12, 2002 | 08:39 AM

cablebandit

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From: Cleveland, OH

help with KR

here is my timing curve:
2400--24
2500--23.5
2600--23
2700--22.5
2800--22
2900--21
3000--19.5
3100--17
3200--16
3300--15.5
3400--15.5
3500--15
3600--15
3700--14.5
3800--14
3900--13
4000--12
4100--12.5
4200--12.5
4300--13
4400--13
4500--13.5
4600--13.5
4700--14
4800--14
4900--15
5000--16
5100--16.5
5200--17
I get 9..yes 9 degrees of KR at 6psi with 93 octane. This occurs at about 4700-4800 rpms. I actually heard an audible ping so I cant assume its false. The car is not lean..actually its a tick rich right now. I wonder what is causing this? I have pulled a lot of timing. I was getting KR at around 4000 but pulled timing to eliminate it. Any ideas? I think this is plenty conservative enuff to run 93 with no kr. I can pull more timing but damn...

Mar 12, 2002 | 11:08 AM

Blackbird

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From: Bellevue, Wa

Re: help with KR

intercooled or non-intercooled?

the powerdyne car @7psi I tuned can run more timing than that on 91 octane. although I am sure you reach your 6psi much faster so that does effect things.

what do your iats look like?

Mar 12, 2002 | 01:00 PM

Reckless

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From: Canton, GA

Re: help with KR

Doesn't look right at all. I was pulling 18 degrees of timing with 10psi on my turbo. Be careful. Even though your O2s say one thing, you fuel system amy be having trouble keeping up with demand.

What I mean is, 4 or 6 of your cylinders may be getting enough fuel to show as "OK" on your O2s, but 2-4 cylinders may be lean in a bad way causing knock. Pull you plugs and compare them.

What kind of fuel system upgrades do you have?
Todd

Mar 12, 2002 | 02:29 PM

cablebandit

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From: Cleveland, OH

Re: help with KR

intercooled. I went to the dyno and tuned for 12.5/1 a/f which showed .915 on my o2s. While tuning I run them at .930 so I feel like I'm ok there. My iats generall show 30 degrees over cruising temp after a 1/4 run. I dont want to just throw 100 octane at it without knowing WHY its doing something it shouldnt. Funny thing is I can run 24 degrees at the track on 8 psi and 100 octane. then i get 4 deg KR . If its pulling 9 on 93 with 15 deg, I wouldnt think it would only pull 4 deg form a max of 24 with 100 octane. my fuel system is lucas 38# injectors with a walbro 340 high pressure pump...10 gauge wire from the pump to a kenney bell boost-a-pump that supplies the pump with 17 volts at 3.5 psi. My fp is a constant 60 psi and I have tuned my pcm accordingly. With the exhaust capped (now the stock catback) and 6-7 psi, I'm probably only making 400 rwhp. I'm tempted to lower the boost to 4 psi and throw in a stock timing curve and see where it pings. I pulled timing in the 3600 range because I had 4 deg kr but i never heard it. im gonna go throw some xylene in and see what it does like it sits now.. Only thing is, roads are wet <img src="gr_sad.gif" border="0"> so no.. <img src="graemlins/formula.gif" border="0" alt="[Pontiac]" />

Mar 12, 2002 | 02:51 PM

Blackbird

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From: Bellevue, Wa

Re: help with KR

I have heard you can actually pull too much timing and cause problems.

Another question now that I know your playing with ls1-edit.

Are you modifying both high and low octane charts?
If your only modding High and the car switched to low and its the stock curve........

Just something to check.

Mar 12, 2002 | 03:51 PM

cablebandit

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From: Cleveland, OH

Re: help with KR

Blackbird are you absolutely SURE about the Hi/low octane charts? I am!!! <img src="gr_grin.gif" border="0"> That was my first screw up <img src="gr_stretch.gif" border="0"> I actually monitor the timing with atap now to make sure

Mar 12, 2002 | 04:46 PM

cablebandit

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From: Cleveland, OH

Re: help with KR

Ok i couldnt get a very good run in but check this out (its raining) i turned boost down to 4.5-5psi Loaded the stock timing curve. At 3200 rpms i got 4 deg kr (28.5 deg down to 24.5) it started giving that timing back till 3900 rpms where i got
8 deg KR (24.5 deg down to 17 deg) It immediately started giving that back to 4500 rpms where i had to let off. This was a 3rd gear pull. 3200 is where i reach full boost at 4.5-5psi...got kr there. 4000 is max tq and i got kr there. Is this crazy or what. Thought i'd certainly hear ping when it pulled 8 deg but i didnt. this was on the same 93 octane. Any ideas? I'm gonna try some 100 octane to see if i can determine whats false and whats not. Still tho...ls1edit is cool! My knock sensor settings are exactly the same as stock. Harlan go ahead and chime in.

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Mar 12, 2002 | 08:34 PM

blackhawk2000

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From: Sterling Heights Mi

Re: help with KR

It's really quite simple. Pull timing until it stops knocking.

Mar 12, 2002 | 08:36 PM

#10

cablebandit

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From: Cleveland, OH

Re: help with KR

yes it was 9 on autotap and of course it showed whatever the timing was afterwards like 7-9 or something like that. In ls1edit it has a "limit" for the amount of timing that can be taken out and mine has zero so it can pull a bunch. Once I saw it pull 22!!!!! This was with my knock sensor disconnected. Something Ed Wright set to save my motor I guess.

Mar 12, 2002 | 10:32 PM

#11

DaveSchott

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From: OH

Re: help with KR

Hmm, still confused, are you saying that LS1Edit allows you to change the parm from a factory value of say 5 to 0 so that ti can pll as much as needed?

And HTH does it pull timing with the knock sensor disconnected? <img src="gr_eek2.gif" border="0">

Blackhawk (John), you miss the point, timing can be removed easily enough via reprogramming, I'm talking about the KR feedback circut and the max (if there is one) it can pull dynamically. It has been stated on several occasions that the LS1 PCM could pull 5 max as delivered from the factory.

Guess its time to buy my own copy of the editor.

Mar 13, 2002 | 12:58 AM

#12

MelloYellow

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From: Centrifugal City

Re: help with KR

Fatten up to 12.2:1
Try a decarb too.
Lower plug gap & range.

Are you TR6?

Mar 13, 2002 | 08:17 AM

#13

blackhawk2000

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From: Sterling Heights Mi

Re: help with KR

Naaa Matt says it will pull more than 4. If he is consistently knocking at a certain RPM point he needs to pull timing until it stops. Peak TQ is around where it will knock the most. After that you can ramp the timing back up.

BTW how is your car coming along Dave?

Mar 13, 2002 | 10:30 AM

#14

DaveSchott

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From: OH

Re: help with KR

<blockquote>quote:<hr />Originally posted by blackhawk2000:
Naaa Matt says it will pull more than 4. <hr /></blockquote>I need to check the Helms, my other ref. book sucks. It did mention that in closed loop the factory pcm administers kr in real time to each cylinder <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> Also, it explained that the KR system is self-calibrating, it looks at the knock signal during cruise and records the reading as normal. Then, when warmed up and WOT, program control advances ignition until knock is perceived, records the signal profile as knock, and then resumes normal timing. Is that <img border="0" title="" alt="[Cool]" src="gr_images/icons/cool.gif" /> or what??

[ March 13, 2002, 10:32 AM: Message edited by: DaveSchott ]

Mar 13, 2002 | 11:04 AM

#15

blackhawk2000

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From: Sterling Heights Mi

Re: help with KR

Yeah our PCM's are pretty advanced

There is also a feature that lowers timing over time if it consistantly picks up KR. It is some type of % scaler.

Mar 14, 2002 | 12:02 AM

#16

2bseen

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From: scottsboro, al

Re: help with KR

not looking very good for sunday looks like rain I hope jr wasn't as bad on the scanner as he was at daytona he wanted to hit the nascar official in the mouth when he wouldn't let him leave pit road without brakes anyway just got back in town still waiting on head gaskets btw do you know where I can get a 11x2 bolt tap thanks tony