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Discussion Starter · #1 ·
My car is retarded. I've got enough mods that I think I should be able to run a 3.0 pulley with no problems. But I'm still seeing KR with a 3.25. I thought it was false but at times it looks to be real, but other times it doesn't show up at all, but sometimes its just a degree or so right after the shifts, but sometimes if 4-5° for several seconds.

Last night I took the S/C belt off (holy crap this car is a dog w/o the S/C) and did a scan. I saw 0°KR the entire time, through all throttle positions and shifts and everything. That makes me think that the KR I see is real. Then I scan with the 3.25 on. I'm only driving on city streets so my only runs were up to 60-70, basically through first gear and the 1-2 shift. My first little jaunt I saw <1°KR, the next time I did a little jaunt from a rolling start through the same speed range and gear change and I only saw KR right after the shifts and only about 1°. Then a minute or so later, from a 35-40 roll, I get into it and downshifts to 2nd and I see +4°KR up to about 70. It spikes up to 4° right after the shift and then slowly goes back down to 0° over about 3 seconds. I'm not sure if my KR recovery is working slow or if its' real KR and the pulled timing is making it slowly disappear?

My KR is so inconsistant that it seems to be false, but when I lose the S/C belt I see NO kr which makes me think that it's real. I have no idea what to do or where I stand. Frustrating!!! Any thoughts?
 

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1998 GTP coupe. All stock and rust free. That will change soon.
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91 Posts
best way to tell if it's real: do a scan then plot KR vs. MAP (boost) and/or KR vs. MAFF
If the only time you get KR is when MAP is above 30 inHg and/or MAFF is > 7KHz then it's real KR.

Remember too about KR recovery is you will only get maximum recovery if the KR is gone after the first event. If there is knock, then the PCM will keep pulling timing until it goes away. Then it will recover and resample. if the KR is still there then it will pull timing again. So you will get a spiky curve. Usually with false KR you'll get a spike but it will recover fairly quickly (assuming the recovery rate is faster than the false knock event e.g. DP hitting swaybar or some harmonic at a certain RPM)
 

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108 Posts
Discussion Starter · #3 ·
Here are several groupings from one 5 minutes scan. Pay no attention to the lack of tuning. I've got idle and cruise relatively close but have not messed with WOT O2's until I figure the KR thing out. Most of them show nothing out of the ordinary, just small blips at shifts and down shift. But on a couple downshifts, one from about 65 into second gear and one from about 50 to second gear, I get strong KR for a couple seconds and then it goes away as it keeps accelerating. It's the KR at these downshifts that bug me. Any thoughts?

Code:
12/09/04 01:37p										
2										
Scan 	RPM	TPS	MPH	LFT1	MAFF	O2L	KR	IGN	B	MISP
mS	RPM	PCT	MPH	PCT	Hz	mV	DEG	DEG	Err	CYL
350	685	0	0	-0.8	2185	530	0	25	0	0
380	649	0	0	-0.8	2229	465	0	25	0	0
360	679	0	0	-0.8	2231	755	0	25	0	3
390	690	0	0	-0.8	2234	525	0	25	0	0
450	749	5.5	0	-3.1	3324	620	0	28	0	0
390	1433	9	0.6	-3.9	3676	430	0	34.5	0	0
350	1550	9	2.5	-3.9	3764	460	0	36.5	0	0
350	1566	9	3.7	-3.9	3764	890	0	36	0	0
350	1599	9	5	-3.1	3762	880	0	36	0	0
350	1602	9	6.8	-3.1	3687	800	0	36	0	0
340	1616	9	8.1	-3.1	3765	645	0	36.5	0	0
360	1672	9.4	9.3	-3.1	3941	870	0	37	0	0
410	1743	11.4	10.6	-3.1	4163	335	0	36.5	0	0
420	1941	14.9	11.8	-3.1	4649	440	0	35.5	0	0
400	2157	17.6	14.3	-3.1	4882	285	0	35	0	0
350	2397	20	16.2	-0.8	5080	340	0	35.5	0	0
380	2506	20	18	1.6	5081	565	0	35.5	0	0
410	2626	21.2	20.5	1.6	5371	535	0	34.5	0	0
410	2867	27.8	23	1.6	5869	265	0	28.5	0	0
440	3249	34.9	26.1	-0.8	6979	940	0	21	0.25	0
400	3528	38.8	29.2	-6.2	8003	955	0	13.5	2.28	0
460	3988	60.8	32.9	-8.6	9279	980	0.17	16	7.66	0
460	4461	98	37.3	-8.6	9870	985	0	15	7.66	0
390	4928	100	42.3	-8.6	10219	995	0	15.5	8.39	0
450	5264	100	45.4	-8.6	10332	990	0	15.5	8.82	0
450	5600	94.1	49.1	-8.6	10528	995	0	16	10.13	0
400	5849	91	52.2	-8.6	10474	990	0	5.5	8.97	0
400	3836	87.1	54.7	-8.6	9259	990	3.8	13.5	8.1	0
490	3940	60	57.2	-8.6	8786	995	4.49	22.5	0	0
380	3315	0	57.2	-5.5	3323	910	0	31	0	0
420	2730	0.4	57.2	-2.3	3060	95	0	30	0	0
370	2079	0.4	55.9	1.6	2813	70	0	27.5	0	0
390	1938	0.4	53.4	3.9	2647	70	0	23	0	0
410	1691	0	51.6	3.9	2542	75	0	18.5	0	0
										
										
400	1141	7.8	21.7	-3.1	3510	945	0	35	0	0
340	1601	8.2	22.4	-3.1	3620	105	0	32.5	0	0
350	1628	8.2	23.6	-3.1	3673	850	0	35	0	0
350	1610	8.2	24.2	-3.1	3592	840	0	33	0	0
340	1626	8.2	24.9	-3.1	3592	490	0	34.5	0	0
350	1620	8.2	25.5	-3.1	3611	855	0	33.5	0	0
350	1607	8.2	26.1	-3.1	3673	645	0	35.5	0	0
410	1720	12.9	26.7	-3.1	4531	875	0	32	0	0
420	2193	24.3	28.6	-0.8	5378	65	0	32.5	0	0
380	2441	25.5	29.8	1.6	5515	165	0	31.5	0	0
410	2455	21.6	31.1	1.6	5006	175	0	37	0	5
400	2003	5.1	32.3	-3.1	3062	585	0	29	0	0
350	1392	0.4	32.9	-0.8	2893	85	0	28	0	0
350	1395	0	32.9	-0.8	2684	810	0	27.5	0	0
350	1310	0	32.3	-0.8	2648	75	0	27	0	0
350	1246	0.4	31.7	-0.8	2562	50	0	27	0	0
360	1242	0.4	31.7	0	2495	45	0	26.5	0	0
350	1241	0.4	31.7	0	2421	110	0	26.5	0	0
420	1232	3.9	31.7	-1.6	2974	910	0	30.5	0	0
420	1570	9	32.3	-3.1	3856	920	0	35	0	0
420	1797	12.5	32.9	-3.1	4780	625	0	26	3.01	0
440	3032	100	33.6	-7	8751	1015	0	17	8.1	0
410	3781	100	35.4	-8.6	9292	1015	0.09	9.5	8.53	0
480	4507	100	39.1	-8.6	10177	1020	0	16	9.12	0
390	5003	100	42.9	-8.6	10336	1020	0	16	9.12	0
400	5243	100	45.4	-8.6	10403	1020	0	16	10.13	0
420	5529	100	47.8	-8.6	10494	1020	0	16	9.7	0
370	5624	100	49.1	-8.6	10773	1015	0	16	10.13	0
410	3749	100	49.7	-8.6	9119	1020	0	17	8.82	0
390	3836	100	54.7	-8.6	9317	1025	0	17.5	9.7	0
400	3905	100	56.5	-8.6	9485	1025	0.43	17	8.53	0
350	3988	100	59	-8.6	9545	1030	0	17.5	9.12	0
400	4049	100	60.9	-8.6	9609	1025	0	17.5	9.55	0
370	4112	100	62.1	-8.6	9639	1025	0	17.5	8.53	0
360	4191	100	64	-8.6	9781	1030	0	17.5	8.53	0
390	4300	100	65.9	-8.6	9764	1025	0	17	9.26	0
370	4401	100	68.4	-8.6	9903	1030	0	17	9.7	0
380	4522	100	70.2	-8.6	9998	1030	0	16.5	8.68	0
360	4569	100	72.1	-8.6	9984	1030	0	16.5	8.82	0
380	4683	100	73.3	-8.6	10160	1030	0	16	9.84	0
380	4768	100	75.8	-8.6	10236	1030	0	16	9.84	0
490	4856	96.5	77.1	-8.6	10180	1030	0	15.5	7.52	0
420	4666	56.5	79.5	-8.6	8638	1020	0	14.5	0.25	0
400	3060	0.4	79.5	-6.2	3297	960	0	32	0	0
390	2931	0.4	79.5	-2.3	3064	945	0	32	0	0
400	2621	0.4	78.3	0	2891	785	0	30.5	0	0
360	1988	0.4	77.1	0	2644	840	0	25.5	0	0
370	1918	0.4	74.6	0	2560	60	0	21	0	0
360	1843	0	72.1	0	2499	50	0	0	0	0
390	1626	0	69.6	0	2422	25	0	0	0	0
360	1443	0.4	68.4	0	2330	15	0	0	0	0
360	1314	0.4	66.5	0	2264	0	0	0	0	0
370	1208	0.4	65.2	0	2213	0	0	0	0	0
360	1116	0.4	64.6	0	2218	0	0	0	0	0
360	1036	0.4	64	0	2185	0	0	2.5	0	0
370	1115	0.4	64	0	2186	0	0	26.5	0	0
370	1347	0.4	63.4	0	2184	15	0	27.5	0	0
340	1443	0.4	63.4	0.8	2139	35	0	27.5	0	0
380	1478	0.8	63.4	0.8	2487	35	0	28.5	0	0
570	1988	34.9	62.8	T.O.	8684	1000	2.16	15	8.1	0
390	3595	100	65.2	-8.6	9139	1010	1.73	13	8.53	0
390	4164	100	67.1	-8.6	9903	1020	1.64	15.5	9.41	0
360	4446	100	68.4	-8.6	9949	1015	1.12	16	9.12	0
390	4507	100	70.8	-8.6	10003	1020	0.6	16	9.7	0
380	4650	100	72.7	-8.6	10177	1015	0.09	16	9.84	0
350	4717	100	75.2	-8.6	10274	1015	0	16	9.7	0
380	4803	100	76.4	-8.6	10312	1015	0	16	9.26	0
360	4910	100	78.3	-8.6	10350	1010	0	16	9.55	0
360	4985	100	79.5	-8.6	10336	1010	0	16	9.26	0
340	5101	100	80.8	-8.6	10321	1015	0	16	10.28	0
370	5160	100	82.6	-8.6	10416	1010	0	16	9.84	0
400	5160	100	83.9	-8.6	10403	995	0	16	9.99	0
350	5264	100	85.1	-8.6	10517	1010	0	16	10.71	0
350	5371	100	86.4	-8.6	10517	995	0	16	11.73	0
400	5328	100	87	-8.6	10486	935	2.07	14	10.71	0
410	5393	100	88.2	-8.6	10656	1000	1.47	14.5	9.55	0
400	5371	43.9	88.2	-8.6	8499	985	0.95	0.5	0	0
410	3331	7.8	88.9	-5.5	3472	935	0	31	0	0
370	3281	0.4	88.9	-2.3	3251	880	0	31	0	0
370	3032	0.4	87.6	0.8	2978	450	0	31	0	0
390	2325	0.4	85.8	0.8	2741	60	0	27.5	0	0
340	2197	0.4	84.5	0.8	2645	35	0	23	0	0
350	2140	0.4	83.9	0.8	2559	40	0	19.5	0	0
360	2046	0.4	82	0.8	2422	20	0	0	0	0
390	1864	0.4	81.4	0.8	2350	0	0	0	0	0
340	1797	0	80.2	0.8	2334	0	0	0	0	0
										
										
350	820	0.4	14.3	-0.8	2374	765	0	25	0	0
340	801	0.4	13	-0.8	2374	840	0	25	0	0
390	829	0.4	12.4	-0.8	2331	740	0	25	0	0
400	827	1.6	11.8	-1.6	2681	590	0	27	0	0
380	1372	10.2	12.4	-6.2	3723	875	0	33	0	0
440	1912	18	13	-5.5	5006	150	0	33	0	0
390	2280	23.9	14.3	-1.6	5345	830	0	32.5	0	0
430	2423	28.6	16.2	1.6	5787	855	0	29	0.83	0
470	2658	35.3	19.3	-1.6	6416	780	0.43	14.5	3.3	0
430	3004	61.2	22.4	-7	8444	990	0	16.5	7.52	0
380	3391	100	24.9	-8.6	8822	1000	0	16.5	7.81	0
370	3825	100	28.6	-8.6	9235	1005	0	17	8.39	0
400	4024	100	32.9	-8.6	9459	1005	0	17	8.53	0
380	4329	100	36	-8.6	9748	1010	0	16.5	8.53	0
410	4683	100	39.8	-8.6	10013	1010	0	15.5	8.68	0
380	5042	100	43.5	-8.6	10321	1015	0	15.5	8.97	0
410	5306	100	46	-8.6	10432	1015	0	16	9.41	0
420	5624	100	49.1	-8.6	10678	1015	0	16	10.13	0
420	4856	100	51.6	-8.6	8934	1000	0	16.5	9.41	0
400	3848	100	54.1	-8.6	9315	1010	0	17	9.12	0
360	3940	100	56.5	-8.6	9343	1005	1.55	15.5	8.82	0
350	3988	100	59	-8.6	9457	1005	1.04	16.5	8.82	0
390	4049	100	60.9	-8.6	9545	1005	0.52	17	8.97	0
370	4164	100	63.4	-8.6	9639	1005	0	17	8.39	0
380	4231	100	65.2	-8.6	9796	1010	0	17	8.53	0
360	4372	100	67.1	-8.6	9827	1005	0	17	8.97	0
390	4476	94.5	69	-8.6	9740	990	0	16.5	8.39	0
510	4522	53.3	71.5	-8.6	9107	990	0	15.5	0	0
370	4177	0.4	71.5	-6.2	3325	930	0	15.5	0	0
400	2818	0.4	72.1	-2.3	3153	900	0	31.5	0	0
380	2664	0	70.8	-2.3	2973	755	0	31.5	0	0
370	2473	0	69	-2.3	2812	45	0	26	0	0
380	1807	0.4	65.2	-2.3	2575	50	0	21.5	0	0
350	1632	0	63.4	-2.3	2537	50	0	0	0	0
400	1375	0.4	61.5	-2.3	2420	15	0	0	0	0
380	1087	0.4	59.7	-2.3	2424	5	0	1	0	0
360	1002	0	57.2	-2.3	2331	10	0	5.5	0	0
380	1207	0	55.3	-1.6	2332	20	0	26.5	0	0
350	1321	0	54.1	-0.8	2264	25	0	27	0	0
350	1334	0.4	52.8	-0.8	2262	35	0	26.5	0	0
340	1313	0	52.2	0	2264	85	0	26.5	0	0
350	1295	0.4	51	0	2233	840	0	26.5	0	0
										
										
390	1246	3.1	49.1	-1.6	2819	830	0	28.5	0	0
400	1509	6.3	48.5	-4.7	3255	790	0	29	0	0
350	1564	6.3	48.5	-4.7	3321	45	0	29	0	0
400	1643	8.2	49.1	-4.7	3762	705	0	36	0	0
360	1910	12.5	49.1	-4.7	4334	150	0	36.5	0	0
360	2021	12.5	49.7	-4.7	4400	100	0	36.5	0	0
340	2037	12.9	49.7	-4.7	4400	720	0	36.5	0	0
350	2034	12.9	50.3	-4.7	4447	130	0	36.5	0	0
490	2056	19.2	51	-3.9	5770	185	0.78	14	7.52	0
410	3331	100	51.6	-8.6	8795	985	4.92	4	8.53	0
390	3665	100	54.1	-8.6	9317	990	4.57	12.5	9.26	0
350	3893	100	55.3	-8.6	9483	995	4.31	13	9.12	0
390	3940	100	57.2	-8.6	9456	995	3.97	13.5	9.41	0
390	4012	100	59.7	-8.6	9545	995	3.45	14	9.12	0
380	4112	100	62.1	-8.6	9634	995	2.85	14	9.12	0
350	4177	100	64	-8.6	9613	995	2.42	14.5	9.12	0
380	4259	100	65.2	-8.6	9796	995	1.9	15	8.97	0
400	4343	100	67.1	-8.6	9827	1000	1.38	15.5	8.82	0
370	4461	100	69.6	-8.6	9903	1000	0.86	15.5	9.26	0
390	4569	100	71.5	-8.6	9984	1000	0.26	16	8.82	0
380	4666	96.5	72.7	-8.6	9998	995	0	15.5	9.41	0
410	4785	90.6	74.6	-8.6	10160	990	0	15.5	9.26	0
360	4856	89.8	76.4	-8.6	10251	995	0	15.5	9.12	0
360	4947	90.6	78.3	-8.6	10257	995	0	15.5	9.12	0
380	5042	90.6	79.5	-8.6	10350	995	0	15.5	9.12	0
350	5120	89.8	81.4	-8.6	10265	990	0	15.5	9.7	0
400	5181	87.1	82.6	-8.6	10403	990	0	16	9.41	0
450	5201	73.3	84.5	-8.6	9701	985	0	15.5	6.21	0
360	3348	0.4	84.5	-7	3321	950	0	31.5	0	0
430	3096	0.4	83.9	-3.1	3067	915	0	31	0	0
370	2753	0.4	81.4	-2.3	2894	720	0	30.5	0	0
380	2050	0.4	78.9	-2.3	2644	670	0	25.5	0	0
 

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do you have poly upper mounts?? When i replaced my stockers with poly's, one of the stockers was actually broken when we pressed it out of the support whole. Threw in the poly's, and KR was 0. I ran a my 3.2 pulley that day at atco, with 0 KR. I couldn't believe it. Something to maybe look into.
 

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Discussion Starter · #5 ·
Frankie said:
do you have poly upper mounts?? When i replaced my stockers with poly's, one of the stockers was actually broken when we pressed it out of the support whole. Threw in the poly's, and KR was 0. I ran a my 3.2 pulley that day at atco, with 0 KR. I couldn't believe it. Something to maybe look into.
I agree 100% and these will be ordered in the next day or so. I've been holding off on these because of hearing stories about bad vibrations transfered from the engine. This seemed to be mainly from the guys that replaced both sets of top mounts, the square ones and the cylindrical ones. I'm only going to do the square ones and see what happens. I believe that will get rid of everything except that issue when I go WOT from a 50 roll. That's my main concern.

Is it possible to get KR from too much fuel?? My WOT O2's are 1000+ at times. Could that be a possibility? It doesn't make sense to me how being too rich would cause KR, but if I'm already rich and seeing KR I don't want to lean out.

BTW- I'm kinda gun shy with ANY kr since my wallet is still recovering from a popped piston incident.
 

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my friend has the xp cam and a ss i/c and has the same problems as you. I still dont think they move enough water/air ratio
 

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Discussion Starter · #7 ·

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Think I might have found the cause of the knock when going WOT from a 50 roll. Looks to be Acceleration Enrichment issues
No Offense to what you think is the solution to your problem, but why is it that I hear people talk about running 0KR all the time and they don't have a tuner to deal with Acceleration Enrichment or Power Enrichment. I think there is a root cause of your problem and you're hastily deciding the Tuner is the only way to resolve your "burst" KR.

I have the same issues as you and I have a LOT more modifications and still have KR. It is disgusting to think that I cannot resolve my KR issues without turning to a Tuner program. There were MANY cars running with 0KR and lots of modifications before any tuners were even available. It just feels like we're jumping onto a bandwagon to eliminate symptoms caused by something that we do not understand or have the time and persistence to track down.
 

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Discussion Starter · #9 ·
I'm not sure about people running 0KR all the time or if they run 0KR while they are scanning. If I go from a stop to a 1/4 mile or 110mph or whatever, I see 0 KR. That is what most people scan. They scan a 0-100 run and see no knock so they assume they run 0KR 100% of the time.

I'm not saying that AE and PE tuning is for sure the problem. I'm saying that my problem fits the symptoms. If you have a better idea of how I might eliminate this burst knock without a tuner, I'd be grateful to hear it. I'd even spend a pretty substantial amount of energy pursuing it. I'd love to lose that knock without a tuner.
 

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With your modifications, I would think you would get 0 KR all the time. Hell, if you look at my modifications, you would think the same too:

3.0 Mag Snout Pulley
MSP Intake
ICCU
Stage 1X Cam
RAT Monster Stage II TB
TOG Headers
MAP I/C
Lucas 42.5lb injectors
9.5:1 CR Diamond Forged Pistons
DHP PCM w/larger injectors table & adjustable timing
Borla Exhaust w/Ubend removed

There is something wrong with both of our cars if we get KR with our modifications. There are many others that run less mods and get 0KR all the time (so they say- I understand your point about logging only once).

I can make a 0-100 run after starting the car up and get 0KR. Several minutes later, I see 3-5 KR consistently throughout the band when I punch it. I can tell you that I have tried to 'tune' out this KR using an ICCU with little success.

All I am saying is don't give up and sell yourself to a tuner. Look for things that may be suspicious. I think the Poly Motor Mounts is a good first stab at trying to resolve your KR. I hope you will post your results- good or bad and how it affected your KR. I am anxious to see the results; as I would likely follow suit if it worked for you. :)

Additionally, I noticed in your logs that you are running very rich when you are getting KR. Under my own observations, I have seen my car respond VERY POORLY to rich O2 values. When I richen up using the ICCU by changing the MAF % by only a few percentage points, my car can see up to 11KR. If I change the MAF values back down, it runs a lot better. If you can reduce the O2 Values by a little (930-940) and then run again, I'd be interested in what your KR values are. I would suspect almost 0.
 

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In a supercharged environment, your early runs will always offer better results versus the following consecutive ones, heat soak of the supercharger is a primary reason for this. If you want consistant runs, one would need to do something that either compensates for this (increase cool down time, ice on the S/C, intercooler) and doesn't overly heat up the intake charge, change the A/F mixture and causing issues like what we are seeing.

Of course I am no uning expert and could be WAY off, but its a strong factor to consider, IMHO. :)

Jut my 2 cents.

JerryH
 
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