MAF calibrations for bigger intakes

[Lex]

Hey Guys and Gals, here are good starting points for the larger MAF calibrations. This is just so you guys are not stuck until a tune happens if you need to drive away with a bigger than stock intake.

JBR

Tru-3.0 Wide Path (3" ID MAF)

0	0	0	0	0	0	0	0	0	0.03	0.05	0.08	0.14	0.19	0.26	0.36	0.44	0.56	0.69	0.83	0.99	1.15	1.35	1.55	1.77	2.02	2.3	2.59	2.9	3.25	3.63	4.08	4.54	5	5.65	6.3	6.94	7.53	8.48	9.13	9.84	10.65	11.54	12.45	13.48	14.61	15.75	16.98	18.64	19.72	21.44	22.7	23.8	25.45	27.19	29.01	30.92	33.33	35.74	37.99	40.32	42.72	45.22	47.82	50.52	53.31	56.22	59.22	62.35	64.56	66.77	68.98	72.33	75.73	79.21	82.77	86.43	90.18	94.04	98.03	107.3	111.78	116.39	121.11	125.96	130.9	135.93	141.01	146.23	151.58	157.05	162.64	168.4	174.31	180.37	186.67	193.19	199.88	206.74	213.77	220.96	228.33	235.86	243.58	251.45	259.47	267.63	275.99	284.53	293.23	302.13	311.22	320.5	329.98	339.67	349.56	359.65	369.94	380.44	391.14	402.08	413.21	424.57	436.15	447.94	459.96	472.23	484.71	497.43

Tru-3.5 Wide Path (3.5" ID MAF)

0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	2.56	2.91	3.28	3.67	4.11	4.59	5.16	5.99	6.81	7.69	8.58	9.45	10.25	11.54	12.43	13.39	14.5	15.71	16.95	18.35	19.49	21.01	22.65	24.86	26.3	28.6	30.28	32.46	34.64	36.47	38.31	40.83	44.01	47.19	50.16	53.23	56.41	59.7	63.14	66.7	70.38	74.22	78.19	82.32	85.23	88.15	91.07	95.5	99.99	104.58	109.28	114.11	119.07	124.16	129.43	141.67	147.59	156.21	164.84	171.45	178.17	185.02	191.93	199.04	206.32	213.76	221.37	229.21	237.26	245.5	254.08	262.95	272.06	281.4	290.96	300.75	310.78	321.03	331.54	342.25	353.17	364.27	375.65	387.28	399.12	411.23	423.61	436.24	449.14	462.33	475.79	489.52	503.53	517.82	532.39	547.28	562.42	577.89	593.65	609.7	626.06	642.76	659.74	677.06

3" (JBR WP 3")

0	0	0	0	0	0	0	0	0	0.02	0.05	0.07	0.12	0.17	0.25	0.32	0.41	0.51	0.64	0.76	0.91	1.06	1.23	1.42	1.63	1.86	2.11	2.38	2.67	2.99	3.34	3.75	4.18	4.6	5.19	5.79	6.38	6.93	7.8	8.4	9.05	9.79	10.61	11.46	12.4	13.44	14.49	15.62	17.16	18.13	19.11	20.09	21.06	22.52	24.06	25.66	27.36	29.14	30.99	32.94	34.96	37.05	39.21	41.46	43.8	46.22	48.74	51.35	54.06	55.98	57.9	59.82	62.72	65.67	68.68	71.77	74.94	78.2	81.54	85	93.04	96.93	100.93	105.02	109.22	113.51	117.87	122.28	126.8	131.44	136.18	141.04	146.02	151.15	156.4	161.86	167.51	173.31	179.27	185.36	191.6	197.99	204.52	211.21	218.04	224.99	232.07	239.32	246.72	254.26	261.98	269.86	277.91	286.14	294.53	303.11	311.86	320.78	329.88	339.16	348.64	358.3	368.15	378.19	388.41	398.84	409.48	420.3	431.33

3.5" WP Silicone (JBR)

0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	2.24	2.55	2.9	3.27	3.67	4.11	4.61	5.16	5.75	6.33	7.03	7.82	8.65	9.58	10.47	11.27	12.15	13.15	14.23	15.37	16.65	18.03	19.44	20.97	22.56	24.18	25.85	27.63	29.56	31.6	33.75	36	38.37	40.87	43.48	46.21	49.04	51.98	55.03	58.17	61.45	64.85	68.37	72.03	75.83	79.79	83.89	88.11	92.39	96.72	101.17	105.72	110.38	115.19	120.11	125.22	130.52	135.98	141.6	147.32	153.22	159.24	165.35	171.54	177.89	185.33	192.77	200.53	208.98	216.3	223.81	231.65	239.73	248.03	257.36	266.7	276.87	288.5	302.78	312.68	322.78	333.09	343.54	354.28	365.24	376.42	387.83	399.49	411.42	423.59	436.04	448.75	461.67	474.89	488.35	502.12	516.15	530.43	545.01	559.86	575.01	590.45	606.2	622.21	638.54

3.5" All aluminum (JBR)

0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	2.08	2.72	3.08	3.24	3.40	3.81	4.27	4.77	5.32	5.87	6.51	7.24	8.01	8.88	9.69	11.79	12.72	13.76	14.88	16.08	17.43	18.86	19.80	21.36	22.98	24.63	26.33	28.14	30.11	32.18	34.37	36.67	39.08	41.63	44.28	47.06	49.94	52.93	56.04	59.24	62.59	66.04	69.63	73.35	77.23	81.25	85.43	89.73	94.09	98.50	103.03	107.66	112.41	117.32	122.33	127.52	132.93	138.48	144.20	150.04	156.04	162.17	168.40	174.69	181.17	187.77	194.55	201.49	208.62	215.94	223.45	231.26	239.34	247.61	256.11	264.83	273.74	282.86	292.20	301.75	311.52	321.44	331.56	341.89	352.48	363.26	374.28	385.55	397.04	408.80	420.80	433.06	445.53	458.30	471.29	484.57	498.10	511.91	525.96	540.30	554.92	569.83	585.01	600.47	616.24

CP-E

3.25" (CPE)

0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.01	0.03	0.06	0.10	0.16	0.23	0.31	0.41	0.53	0.66	0.81	0.97	1.16	1.36	1.58	1.82	2.09	2.38	2.70	3.04	3.41	3.82	4.28	4.79	5.34	5.89	6.54	7.26	8.03	8.90	9.73	10.47	11.28	12.20	13.22	14.28	15.46	16.75	18.06	19.48	20.96	22.46	24.01	25.66	27.45	29.35	31.35	33.44	35.65	37.97	40.39	42.92	45.55	48.28	51.10	54.03	57.07	60.23	63.51	66.91	70.44	74.12	77.92	81.84	85.81	89.85	93.97	98.20	102.54	106.99	111.57	116.31	121.24	126.31	131.52	136.85	142.32	147.92	153.59	159.35	165.24	171.27	177.45	183.78	190.28	196.95	203.81	210.93	218.29	225.84	233.59	241.54	249.67	258.00	266.52	275.23	284.12	293.18	302.42	311.85	321.48	331.33	341.38	351.65	362.14	372.86	383.80	394.97	406.37	418.00	429.86	441.96	454.31	466.89	479.72	492.81	506.14	519.73	533.58	547.69	562.06

SURE

3" (SURE)

0	0	0	0	0	0	0	0	0	0.03	0.05	0.08	0.14	0.19	0.27	0.36	0.45	0.56	0.7	0.84	1	1.16	1.36	1.56	1.79	2.04	2.32	2.62	2.93	3.29	3.67	4.12	4.59	5.06	5.71	6.36	7.01	7.61	8.57	9.23	9.94	10.76	11.66	12.58	13.62	14.76	15.91	17.16	18.84	19.92	20.99	22.06	23.13	24.73	26.43	28.19	30.05	32	34.04	36.18	38.4	40.69	43.07	45.54	48.11	50.77	53.54	56.4	59.38	61.49	63.59	65.7	68.89	72.12	75.44	78.83	82.31	85.89	89.56	93.36	102.19	106.46	110.85	115.34	119.96	124.67	129.46	134.3	139.27	144.36	149.57	154.9	160.38	166.01	171.78	177.78	183.99	190.36	196.9	203.59	210.44	217.46	224.63	231.98	239.48	247.11	254.89	262.85	270.98	279.27	287.74	296.4	305.24	314.27	323.5	332.91	342.52	352.32	362.32	372.51	382.93	393.53	404.35	415.38	426.61	438.06	449.74	461.63	473.74

3.25" (SURE) BETA

0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	0.00	2.10	2.39	2.72	3.07	3.44	3.86	4.31	4.84	5.39	5.94	6.70	7.46	8.23	8.93	10.06	10.83	11.67	12.63	13.68	14.76	15.98	17.32	18.67	20.14	22.11	23.38	24.63	25.89	27.15	29.02	31.02	33.08	35.27	37.56	39.95	42.46	45.07	47.75	50.55	53.45	56.46	59.58	62.84	66.19	69.69	72.17	74.63	77.11	80.85	84.64	88.54	92.52	96.60	100.80	105.11	109.57	119.93	124.94	130.09	135.36	140.79	146.31	151.94	157.62	163.45	169.42	175.54	181.79	188.22	194.83	201.60	208.64	215.93	223.41	231.08	238.94	246.97	255.21	263.63	272.25	281.06	290.01	299.14	308.48	318.03	327.75	337.69	347.86	358.23	368.83	379.66	390.71	401.99	413.49	425.22	437.18	449.41	461.85	474.55	487.49	500.67	514.11	527.82	541.77	555.99

HTP

3" (HTP)

0	0	0	0	0	0	0	0	0	0.03	0.05	0.08	0.14	0.19	0.27	0.36	0.46	0.57	0.71	0.85	1.01	1.17	1.38	1.58	1.81	2.06	2.35	2.65	2.97	3.33	3.71	4.17	4.65	5.12	5.78	6.44	7.09	7.7	8.67	9.34	10.06	10.89	11.8	12.73	13.78	14.94	16.1	17.37	19.07	20.16	20.94	21.72	22.77	24.34	26.02	27.75	29.58	30.92	32.26	34.28	36.39	38.56	40.23	43.23	46.24	48.79	51.44	54.2	57.06	59.09	61.11	63.14	66.2	69.31	72.49	75.75	79.09	82.53	86.06	89.72	98.2	102.31	106.52	110.84	115.28	119.8	124.4	129.06	133.84	138.73	143.73	148.86	151.91	154.97	158.02	161.08	166.7	172.47	178.4	184.46	190.67	197.02	203.53	210.18	216.98	223.9	230.95	238.16	245.52	253.02	260.71	268.55	276.56	284.75	293.11	301.63	310.34	319.22	328.28	334.14	343.49	353	362.69	372.59	382.67	392.93	403.41	414.07	424.94

3.5" (HTP)

0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	2.49	2.84	3.24	3.65	4.09	4.59	5.11	5.75	6.41	7.06	7.96	8.87	9.77	10.61	11.95	12.87	13.86	15.01	16.26	17.54	18.99	20.59	22.19	23.94	26.28	27.78	28.86	29.93	31.38	33.54	35.86	38.24	40.76	42.61	44.45	47.24	50.15	53.14	55.44	59.57	63.72	67.23	70.88	74.69	78.63	81.43	84.21	87.01	91.22	95.51	99.89	104.38	108.99	113.73	118.59	123.63	135.32	140.98	146.78	152.74	158.86	165.08	171.42	177.84	184.43	191.17	198.06	205.13	209.33	213.55	217.75	221.97	229.71	237.66	245.84	254.19	262.74	271.49	280.46	289.63	299.00	308.53	318.25	328.18	338.33	348.66	359.26	370.06	381.10	392.39	403.91	415.65	427.65	439.89	452.37	460.44	473.33	486.43	499.79	513.43	527.32	541.46	555.90	570.59	585.57

4" (HTP) Beta

0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	3.22	3.67	4.18	4.71	5.28	5.93	6.60	7.43	8.28	9.12	10.28	11.46	12.62	13.70	15.43	16.62	17.90	19.39	21.00	22.65	24.53	26.59	28.66	30.92	33.94	35.88	37.28	38.66	40.53	43.32	46.32	49.39	52.65	55.04	57.41	61.02	64.77	68.64	71.61	76.94	82.30	86.83	91.55	96.47	101.56	105.17	108.77	112.38	117.82	123.36	129.02	134.82	140.77	146.89	153.17	159.68	174.78	182.09	189.58	197.28	205.18	213.22	221.41	229.70	238.21	246.92	255.81	264.95	270.37	275.82	281.25	286.70	296.69	306.96	317.53	328.31	339.35	350.66	362.24	374.09	386.19	398.50	411.05	423.88	436.99	450.33	464.02	477.97	492.23	506.81	521.69	536.85	552.35	568.16	584.28	594.70	611.35	628.27	645.53	663.15	681.09	699.35	718.00	736.97	756.32

Corksport

3" (CS) Beta

0.00	0.00	0.00	0.00	0.00	0.00	0.02	0.02	0.02	0.03	0.04	0.09	0.13	0.20	0.27	0.39	0.47	0.63	0.73	0.89	1.06	1.29	1.41	1.54	1.88	2.06	2.33	2.65	3.10	3.45	3.82	4.20	4.68	5.24	5.81	6.38	7.12	7.75	8.09	8.74	9.80	11.10	12.04	12.95	13.52	14.65	15.80	16.88	18.08	19.26	20.62	21.87	22.55	24.90	27.71	29.13	30.96	32.79	34.09	36.65	38.87	41.01	43.12	45.93	49.42	51.51	54.00	57.10	59.73	63.07	67.17	70.83	74.86	79.73	81.85	86.35	90.72	95.33	99.72	105.61	111.87	116.75	125.12	129.98	138.82	144.28	147.08	153.40	157.56	161.62	167.14	173.09	179.23	185.49	191.96	198.66	205.62	210.51	217.74	225.14	232.72	240.48	248.40	256.54	264.82	273.27	281.88	290.68	299.68	308.82	318.19	327.76	337.52	347.54	357.74	368.16	378.75	389.61	400.65	411.93	423.47	435.17	447.13	459.32	471.76	484.42	497.33	510.50	523.87

How to apply the MAF cal:

If you have an MS6, or Gen1 MS3 you need to copy the above data for the intake you have installed in the following 2 tables (MAF Table A and MAF Table B) in your ATR software. These tables must be identical. After you have copied this, save your map and flash it on the car.

If you have a Gen2 MS3 the process is the same except that you only have ONE MAF table instead of 2 (MAF Table A).

To verify that the MAF calibration is correct, drive 40 miles normally. Then take a MAF calibration log and observe the LTFTs. Ideally they should be no more than +/-10%. If this is the case then go ahead and do a WOT log. Here look that your AFR targets are met and there isn't more than a 0.2-0.3 AFR deviation from the targets under steady WOT operation.

There is no need to chase the "ideal" 0% LTFT. The LTFTs change with weather, fuel used, and even if you use the A/C a lot. The ECU is constantly adjusting and learning and as long as the LTFTs are within +/-10% you are running a suitable MAF Calibration. Your car will not run any *better* with 0% LTFTs versus 5% LTFTs. However if the LTFTs start to drift above 10% while no hardware changes have been made to the car, this indicates there is an issue and most often it is an intake or an exhaust leak.

[lilred]

So kind and generous I wish I had more money for a GA and tune now!

tapafuck

[exentix]

welp seems like you got it figured out lol. my cars running more than fine with my jbr intake. that @Lex guy knows what hes doing

[Haltech]

Thanks for sharing Alex

[2012FailWheelDrive]

subbed plan on goin with jbr soon.

[Deldran]

@Lex

Could you possibly give us the multiplier maybe I am wrong but would it just be easier to highlight the whole mad cal and multiply it.

I know jbr is around ~1.66

Thanks

Sent from galaxy Nexus vis CM10

[802MS3]

just fyi with the JBR intake, you should probably just zero out anything below 0.9v. @Ziggo figured out that this will trip the Crank Position Sensor circut malfunction CEL because the KOEO voltage is around .9 when its scaled so much. The ECU sees no airflow and thinks there should be at that voltage, or something like that ha. I used to get the CEL occasionally, and since I've zero'd out everything below 0.9v, the CEL has not returned.

[Lex]

Originally Posted by 802MS3 just fyi with the JBR intake, you should probably just zero out anything below 0.9v. @Ziggo figured out that this will trip the Crank Position Sensor circut malfunction CEL because the KOEO voltage is around .9 when its scaled so much. The ECU sees no airflow and thinks there should be at that voltage, or something like that ha. I used to get the CEL occasionally, and since I've zero'd out everything below 0.9v, the CEL has not returned.

Good point OP updated.

[dale_gribble]

Quick question @Lex, Sure offers two 3" systems- one 3" system with a 2.5" MAF housing (Sure Full 3 Aeros) and a 3" system (Sure 3" Full 3 Aeros) with a 3" MAF housing. Can you confirm which of these systems your 3" SURE starting point represents?

[dantes5823]

Good stuff lex.

[Lex]

Originally Posted by dale_gribble Quick question @Lex, Sure offers two 3" systems- one 3" system with a 2.5" MAF housing (Sure Full 3 Aeros) and a 3" system (Sure 3" Full 3 Aeros) with a 3" MAF housing. Can you confirm which of these systems your 3" SURE starting point represents?

The MAF curve is for 3" inner diameter MAF housing. The 2.5" inch is their stock sized housing.

[Pierre Loubser]

My car has a Gtx3071 turbo.Which Sure Aeros unit would you suggest.Sure 3.0" or 3.25" Maf.

[ASHMS3]

Bigger MAF = more airflow potential = more power potential

[Bobforapples]

Originally Posted by Lex Hey Guys and Gals, here are good starting points for the larger MAF calibrations. This is just so you guys are not stuck until a tune happens if you need to drive away with a bigger than stock intake. 3" (SURE) 0 0 0 0 0 0 0 0 0 0.03 0.05 0.08 0.14 0.19 0.27 0.36 0.45 0.56 0.7 0.84 1 1.16 1.36 1.56 1.79 2.04 2.32 2.62 2.93 3.29 3.67 4.12 4.59 5.06 5.71 6.36 7.01 7.61 8.57 9.23 9.94 10.76 11.66 12.58 13.62 14.76 15.91 17.16 18.84 19.92 20.99 22.06 23.13 24.73 26.43 28.19 30.05 32 34.04 36.18 38.4 40.69 43.07 45.54 48.11 50.77 53.54 56.4 59.38 61.49 63.59 65.7 68.89 72.12 75.44 78.83 82.31 85.89 89.56 93.36 102.19 106.46 110.85 115.34 119.96 124.67 129.46 134.3 139.27 144.36 149.57 154.9 160.38 166.01 171.78 177.78 183.99 190.36 196.9 203.59 210.44 217.46 224.63 231.98 239.48 247.11 254.89 262.85 270.98 279.27 287.74 296.4 305.24 314.27 323.5 332.91 342.52 352.32 362.32 372.51 382.93 393.53 404.35 415.38 426.61 438.06 449.74 461.63 473.74 3.25" (CPE) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.03 0.06 0.10 0.16 0.23 0.31 0.41 0.53 0.66 0.81 0.97 1.16 1.36 1.58 1.82 2.09 2.38 2.70 3.04 3.41 3.82 4.28 4.79 5.34 5.89 6.54 7.26 8.03 8.90 9.73 10.47 11.28 12.20 13.22 14.28 15.46 16.75 18.06 19.48 20.96 22.46 24.01 25.66 27.45 29.35 31.35 33.44 35.65 37.97 40.39 42.92 45.55 48.28 51.10 54.03 57.07 60.23 63.51 66.91 70.44 74.12 77.92 81.84 85.81 89.85 93.97 98.20 102.54 106.99 111.57 116.31 121.24 126.31 131.52 136.85 142.32 147.92 153.59 159.35 165.24 171.27 177.45 183.78 190.28 196.95 203.81 210.93 218.29 225.84 233.59 241.54 249.67 258.00 266.52 275.23 284.12 293.18 302.42 311.85 321.48 331.33 341.38 351.65 362.14 372.86 383.80 394.97 406.37 418.00 429.86 441.96 454.31 466.89 479.72 492.81 506.14 519.73 533.58 547.69 562.06 3.5" (JBR) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 1.82 2.08 2.72 3.08 3.47 3.40 3.81 4.27 4.77 5.32 5.87 6.51 7.24 8.01 8.88 9.69 11.79 12.72 13.76 14.88 16.08 17.43 18.86 19.80 21.36 22.98 24.63 26.33 28.14 30.11 32.18 34.37 36.67 39.08 41.63 44.28 47.06 49.94 52.93 56.04 59.24 62.59 66.04 69.63 73.35 77.23 81.25 85.43 89.73 94.09 98.50 103.03 107.66 112.41 117.32 122.33 127.52 132.93 138.48 144.20 150.04 156.04 162.17 168.40 174.69 181.17 187.77 194.55 201.49 208.62 215.94 223.45 231.26 239.34 247.61 256.11 264.83 273.74 282.86 292.20 301.75 311.52 321.44 331.56 341.89 352.48 363.26 374.28 385.55 397.04 408.80 420.80 433.06 445.53 458.30 471.29 484.57 498.10 511.91 525.96 540.30 554.92 569.83 585.01 600.47 616.24

Not questioning your knowledge but from what I had read you don't want dips in the MAF curve. Noticed on the JBR numbers at 1.05v corresponds with 3.47 and the next one, 1.09v is 3.40. I trust you so I'm still going to use the numbers you put ^.^ Didn't know if maybe a typo?

Thanks for the useful info tho =D

[helmetface]

Originally Posted by Pierre Loubser My car has a Gtx3071 turbo.Which Sure Aeros unit would you suggest.Sure 3.0" or 3.25" Maf.

3.5"


By the way, your signature says gt35..

[Lex]

Originally Posted by Bobforapples Not questioning your knowledge but from what I had read you don't want dips in the MAF curve. Noticed on the JBR numbers at 1.05v corresponds with 3.47 and the next one, 1.09v is 3.40. I trust you so I'm still going to use the numbers you put ^.^ Didn't know if maybe a typo? Thanks for the useful info tho =D

Good eye. It should increase with voltage so that is a small error but in reality it won't make a big difference in how the car runs since the airflow values are very low to begin with. I have interpolated the area and updated cals in the OP.

[CamSpeed360]

So is this something we can copy/paste? I'm not sure how to implement these values into ATR without typing each cell in individually.

Thank you @Lex for all of this.


Edit- I figured it out.

Copy
Highlight all cells
Edit Tab>Paste Copied Cell Values

[dantes5823]

Originally Posted by CamSpeed360 So is this something we can copy/paste? I'm not sure how to implement these values into ATR without typing each cell in individually. Thank you @Lex for all of this.

Copy and paste

[3starmagnum]

Subbed for future MAF size increase

[pwdunmore]

I just installed my JBR intake and did the MAF calibration(mulitple times to get it tuned in) this thread which was a great start

I am at 0.9V at idle and at 14.8 AFR but after idling for a minute I go to 15.2 AFR and a 1.0V for a couple of seconds then it goes back down to normal... It seems to cycle through this every couple of minutes but is stable 99% of the time.

Any idea what this is caused from? I ordered a MAF air straightener to see if that would solve the issue. My idle is stable but bumps up once in a while by the ECU(I think). Idles at ~750rpm then gets bumped to ~800rpm for a couple of seconds.

[Domino81]

@Lex;, is there one you endorse more than another?

[himurax13]

@Lex,

Have you seen the new 4" MAF intake?

[Lex]

Originally Posted by pwdunmore I just installed my JBR intake and did the MAF calibration(mulitple times to get it tuned in) this thread which was a great start I am at 0.9V at idle and at 14.8 AFR but after idling for a minute I go to 15.2 AFR and a 1.0V for a couple of seconds then it goes back down to normal... It seems to cycle through this every couple of minutes but is stable 99% of the time. Any idea what this is caused from? I ordered a MAF air straightener to see if that would solve the issue. My idle is stable but bumps up once in a while by the ECU(I think). Idles at ~750rpm then gets bumped to ~800rpm for a couple of seconds.

Sounds like a bit of an unstable idle which has been reported with the JBR. I would bump base idle to 925 to see if the extra air can help stabilize the MAF reading.

Originally Posted by Domino81 @Lex;, is there one you endorse more than another?

You mean an intake? Lol the Lex seal of endorsement!

Originally Posted by himurax13 @Lex, Have you seen the new 4" MAF intake?

Haven't seen it installed on a car yet. You're going to throw it on?

[CamSpeed360]

Originally Posted by pwdunmore I just installed my JBR intake and did the MAF calibration(mulitple times to get it tuned in) this thread which was a great start I am at 0.9V at idle and at 14.8 AFR but after idling for a minute I go to 15.2 AFR and a 1.0V for a couple of seconds then it goes back down to normal... It seems to cycle through this every couple of minutes but is stable 99% of the time. Any idea what this is caused from? I ordered a MAF air straightener to see if that would solve the issue. My idle is stable but bumps up once in a while by the ECU(I think). Idles at ~750rpm then gets bumped to ~800rpm for a couple of seconds.

Mine does the exact same thing. And it seems to want to idle lower than i have the idle set half the time. But lex numbers were awesome. My ltft are within 2% without any calibration.

[pwdunmore]

Okay, as long as I am not alone with the issue. If i stumble apon a solution I will post it. Thanks guys

Just need to get my HTP battery tray to make some room... holy crap it's crowded in there right now.

Edit: Issue solved, main problem was with front defrost on the engine bumps up rpms periodically even though the A/C button is off.

[himurax13]

Originally Posted by Lex Haven't seen it installed on a car yet. You're going to throw it on?

Nah, I will let some other gineau pig try it first. However, if I did manage to get one, would it throw off my tune after I do a maf cal?

[Lex]

Originally Posted by himurax13 Nah, I will let some other gineau pig try it first. However, if I did manage to get one, would it throw off my tune after I do a maf cal?

I will say no for now. The only thing it may throw off is boost control. You you see it go above targets or oscillate, then it will need a touchup.

[alfre127]

any maps for the SURE 3.25" Full3 Aeros ?

[MS3 Ventura]

I just installed the SURE 3.25" Full3 Aeros today. Also installed a GTX3071R. Just waiting to install a map to start it up.

For the SURE 3.25" Full3 Aeros, I will try using the CPE 3.25" MAF cal above and see if that works.

[Lex]

Originally Posted by MS3 Ventura I just installed the SURE 3.25" Full3 Aeros today. Also installed a GTX3071R. Just waiting to install a map to start it up. For the SURE 3.25" Full3 Aeros, I will try using the CPE 3.25" MAF cal above and see if that works.

It should be quite close. Depending on the car and other parts installed you may need a tweak to the MAF cal here and there but the ones posted will certainly get the car started and running for tuning.

[CamSpeed360]

I'm sorry if I've misinterpreted but in some other thread I read that there are other tables that may need adjustment for the car to idle correctly with the larger intakes? Is that something you could shed some light on @Lex;? I remember reading something about clutch out comp or some shit like that. I'm newb to this stuff.

[Lex]

The shift tables are not related to idle quality - just shift behavior. For the 3.5"+ intakes it is recommended to zero out the 0-0.9V MAF range which the calibration above already does for the 3.5.

[CamSpeed360]

Yeah I knew about that part. Hmm. I took my intake off because the idle was so screwy.

[Voltwings]

I'm currently on a 3" so to go to 4" ill need to scale roughly 30-35% for the MAF. Realistically i think i would like to use the injector scalar tables to keep a tighter MAF curve, less distance between the break points seems like it would be more accurate and run smoother. On that same note however, im not exactly sure that scaling the injectors up 30-35% on top of the 10% they already are for e85 is a good idea. At any rate just any info yall can shed on the subject would be great, got a Few bolt on C5's that called me out this friday so i gotta make sure i bring my big boy intake haha. Thanks.

[Lex]

Originally Posted by Voltwings I'm currently on a 3" so to go to 4" ill need to scale roughly 30-35% for the MAF. Realistically i think i would like to use the injector scalar tables to keep a tighter MAF curve, less distance between the break points seems like it would be more accurate and run smoother. On that same note however, im not exactly sure that scaling the injectors up 30-35% on top of the 10% they already are for e85 is a good idea. At any rate just any info yall can shed on the subject would be great, got a Few bolt on C5's that called me out this friday so i gotta make sure i bring my big boy intake haha. Thanks.

The fomula for scaling the MAF is the following:

New MAF Curve = Old MAF Curve * (new MAF diameter ^ 2 / old MAF diameter ^ 2)

Scaling the injectors may not be the answer you're looking for. Depending on where COBB inserted the injector scaling calculation, you will probably end up in the same boat in terms of resolution. In a multiplication if you scale the first term (MAF let's say) versus scaling the 3rd term (inj multiplier let's say) the cost to resolution is absolutely the same.

On top of this, your loads will all be off since your new MAF will consistently read lower than your current tune. That messes with every table in the tune.

Finally, I have found that on large airflow setups (big turbo) the injector scalar can have unpredictable effects and result in the car running leaner than commanded in the midrange.

So in conclusion, it is best to have your sensors read accurately so just scale the MAF accordingly and set the 0-0.9V region to 0 to avoid CELs. Remember that idle issues have nothing to do with the MAF scaling, they have to do with the fact that the sensor itself is sampling such a small amount of air in a very large pipe and the VOLTAGE output will be very small. That's where the resolution problems come from, not from the scaling of the curve.

[Voltwings]

Im on a pure boost tune so i'm not terribly concerned with load, but thats more or less the answer i was looking for, thanks.

[CamSpeed360]

So do we have a way of making the car idle properly on the larger intakes? Also, for some reason, I raised my idle in ATR and it was still stuck down around 650rpms... I even tried raising it to 1100 and nothing changed... I'm assuming that's a problem in its own. But maybe its related.

[Lex]

Originally Posted by CamSpeed360 So do we have a way of making the car idle properly on the larger intakes? Also, for some reason, I raised my idle in ATR and it was still stuck down around 650rpms... I even tried raising it to 1100 and nothing changed... I'm assuming that's a problem in its own. But maybe its related.

Focus here is to get a good air sample to the sensor with little turbulence and no leaks around the MAF o-ring.

[CamSpeed360]

Originally Posted by Lex Focus here is to get a good air sample to the sensor with little turbulence and no leaks around the MAF o-ring.

So you're suggesting an air straighter? Everything else is sealed. Or was. My car is stocked out at the moment.

[Lex]

Originally Posted by CamSpeed360 So you're suggesting an air straighter? Everything else is sealed. Or was. My car is stocked out at the moment.

If the readings are turbulent/fluctuate. Look closely at MAF voltage since that's the root of the measurement