Subject	The relationship is rather simple - I derived an equation
Posted by	Ash's Z on October 03, 2006 at 10:24 AM
	This message has been viewed 220 times.
In Reply To	So what sort of equation are we going to assume... posted by Kenny on October 03, 2006 at 09:04 AM
Message	several years ago to relate MAS voltage to an airflow rating as it is necessary in order to calculate theoretical pulsewidth, which is used heavily in the ZEMulator software. Unfortunately, that equation converts the voltage into an arbitrary airflow value spread across a 16-bit scale. The nice thing about this is the fact that the VQ table in the ECU program relates voltage to this arbitrary airflow value so it will be easy to cross-check the consistency in measurements obtained at the flowbench. I just didn't use the lookup table (VQ Table) in the ZEM as I found an easier way to do it with the equation. The equation is as such: AirflowValue = (MASVoltage/.08)*0.5^3.2 Theoretical pulsewidth is a calculation that takes the airflow value times the injector constant, divided by RPM divided by 50 times 180-degrees, divided by 6. The Theoretical pulsewidth value divided by 8 equals the injector pulsewidth. So, a MAS voltage of 3.44 = an airflow value of 18357. 18357 * 288 (injector K for 370cc injectors) = 5286832 Say this is at 4000RPM, so the divisor is 14400. The TP value in this case is 61.2. The Injector pulsewidth for TP is 7.65ms. The equation I used isn't dead on in every case to the lookup table, but it is within about 1%, which is plenty close enough for just about any purpose of analysys. Airflow value calculated at 3.44V using equation:18357 Airflow value in lookup table value for 3.44V: 18141 [ ashspecz.com ] [ agpowers@bellsouth.net ] Enthusiasts soon understand each other. --W. Irving. Are you an enthusiast? If you are out to describe the truth, leave elegance to the tailor. Albert Einstein
Follow Ups	Going to the flowbench tomorrow >>>>> - Ash's Z 23:48:40 10/02/06 what's the picture gonna be used for? (n/m) - inf 23:58:14 10/02/06 To keep me in check. :) (n/m) - Ash's Z 00:01:17 10/03/06 I have an HKS intake you may use to check against.. - Shawn300zTT GT28R MD 00:23:56 10/03/06 Also, Have you thought about flowing a stock 52mm - Shawn300zTT GT28R MD 00:25:43 10/03/06 2nd.. i wouldnt mind seeing the flow differences - fst300zx 00:52:29 10/03/06 Well.. - Shawn300zTT GT28R MD 01:12:51 10/03/06 dyno tune was 11:5 ..seeing 10:8 or 11:1 on the street .. - The Devils Z 08:59:07 10/03/06 i can send you some apexi filters I have at the house - maglito 00:44:50 10/03/06 Cool :) (n/m) - RedBeauty84zx (San Antonio) 01:02:18 10/03/06 Hey! I have that same 12V power supply... - Zluster(Abudan) 01:11:58 10/03/06 Your wife in the pic looks like "Stifflers Mom" lol (n/m) - PiotrC70 01:24:40 10/03/06 I can see it already happening, Your gonna test the Pop - Eishozzzz 05:45:36 10/03/06 Are you busting my balls here or are you being sarcastic? - Ash's Z 09:59:34 10/03/06 I wouldn't call the other flow tests "flawed" - aliaZ 06:13:55 10/03/06 "flawed" or not, perhaps AliaZ could arrange .... - I-xclr8 09:58:52 10/03/06 It is safe to say that if an independent comparison - Guapo 10:05:36 10/03/06 I Nominate Steve Millen (n/m) - Adam (NoVA) 10:08:16 10/03/06 nope ... his connection to JWT could be called into question (n/m) - Guapo 10:11:54 10/03/06 I still contend that there is no way... - I-xclr8 10:35:24 10/03/06 Fear? What are you talking about? - Adam (NoVA) 10:40:44 10/03/06 Send Mike Smith my manifolds for... - I-xclr8 10:55:59 10/03/06 you make no point - Adam (NoVA) 11:02:10 10/03/06 I didn't say there was no objective judge. I said - Guapo 10:45:16 10/03/06 Well, quit talking about it and do it. (n/m) - Ash's Z 11:17:21 10/03/06 ok. I nominate Damon. (n/m) - Guapo 11:22:48 10/03/06 Fair enough. I'll do my tests, and we'll let Damon do the - Ash's Z 14:20:08 10/03/06 Re: Fair enough. I'll do my tests, and we'll let Damon do t - Guapo 14:43:45 10/03/06 Cute, and clever..... but you didn't answer my question. - Ash's Z 00:36:15 10/04/06 My opinion is that you do not have the overall standing in - Guapo 09:54:51 10/04/06 I'm not concerned if people discard the data I provide. - Ash's Z 13:05:01 10/04/06 cool. Look forward to seeing them. (n/m) - Guapo 14:52:43 10/04/06 He's gonna fry you :D - SeedyROM 17:34:29 10/03/06 I dont think Damon needed to be pulled into this. - Ash's Z 00:42:35 10/04/06 "why put it down before it is even disclosed?" - Guapo 09:56:18 10/04/06 does deadly have a bong to even test off of? (n/m) - Halo Z 22:03:01 10/03/06 I would think the suppliers should all concur on a test haus - BigTDogg (MA) 10:51:23 10/03/06 what he said (n/m) - Adam (NoVA) 10:53:03 10/03/06 as I've said before - aliaZ 12:29:12 10/03/06 I would way rather have somthing that is - Shawn300zTT GT28R MD 12:39:42 10/03/06 As would 98% of the members here. Very niche market - BigTDogg (MA) 12:46:28 10/03/06 agreed (n/m) - Adam (NoVA) 13:43:35 10/03/06 Actually Shawn, you wouldn't and you dont. - Ash's Z 14:27:57 10/03/06 bah.. details..:) - Shawn300zTT GT28R MD 16:29:16 10/03/06 At some point people buy new downpipes... - I-xclr8 13:12:12 10/03/06 at some point people *upgrade* to new downpipes - aliaZ 17:07:43 10/03/06 i though the manifold where for air flow. - Halo Z 22:05:17 10/03/06 LOL. (n/m) - Inzane 10:44:38 10/03/06 U get jokes? :) (n/m) - Adam (NoVA) 10:45:52 10/03/06 Just videotape the entire flowbench session :) (n/m) - Kick'n 10:21:12 10/03/06 FWIW, I could care less about who lets middleschool - Ash's Z 10:40:17 10/03/06 I said nothing about your contributions to the Z32 - Guapo 10:49:44 10/03/06 Thanks for your opinion. (n/m) - Ash's Z 11:15:34 10/03/06 Oh please. - Kenny 11:50:13 10/03/06 . (n/m) - Ash's Z 11:57:37 10/03/06 This test will clarify nothing - Adam (NoVA) 10:24:08 10/03/06 Their test was not properly set up. - Ash's Z 11:38:31 10/03/06 Sure it was. - Kenny 11:45:06 10/03/06 They only flowtested one port of three in the manifolds - Ash's Z 11:48:34 10/03/06 The data is not inaccurate, it is incomplete though. - Kenny 11:52:09 10/03/06 The data is inaccurate because it does not represent the - Ash's Z 13:42:14 10/03/06 The data is not inaccurate, your inferences are. - Kenny 16:48:08 10/03/06 OK, here's an example of what I mean: - Ash's Z 00:19:08 10/04/06 testing individual components vs. parts of a system - maglito 01:42:00 10/04/06 actually - aliaZ 09:47:28 10/04/06 I think he was asking why the original tests - maglito 15:17:54 10/04/06 You make valid points, then an invalid conclusion. - Kenny 11:27:29 10/04/06 I dont think you understand how different some heads can - Ash's Z 13:15:50 10/04/06 I'm not sure where you got that from. - Kenny 13:59:54 10/04/06 So what sort of equation are we going to assume... - Kenny 09:04:17 10/03/06 The relationship is rather simple - I derived an equation - Ash's Z 10:24:52 10/03/06 Cool =). (n/m) - Kenny 10:28:47 10/03/06 OOooo.. giving out the recipe for secret sauce :-) (n/m) - spicyZ 10:35:38 10/03/06 Hehehe.. I should shoot myself in the right foot. (n/m) - Ash's Z 01:06:33 10/04/06 Can you supply a full derivation for that equation? - CaliguyPurdue 15:33:06 10/03/06 The equation the way I explained it can be simplified. - Ash's Z 01:05:38 10/04/06 Thanks for doing this Ash, I look forward to the results - 300zx90 (CO) 09:11:04 10/03/06 Hey Ash - Tony@GZperformance 09:21:04 10/03/06 who's is that?????? i mean what company... (n/m) - Zski 09:26:09 10/03/06 Its the GReddy unit that comes with its FMIC's (n/m) - Shawn300zTT GT28R MD 12:43:01 10/03/06 I'm game for it. Email me - (n/m) - Ash's Z 12:08:06 10/03/06 have fun! can't wait for some results (n/m) - Seb (specialty-Z) 10:32:32 10/03/06 cool - Adam (NoVA) 10:51:06 10/03/06 Yeah, the response to the testing of the manifolds was - Ash's Z 11:12:48 10/03/06 Well, it may not be a bad place to start compiling that - Adam (NoVA) 11:18:14 10/03/06 Stop it. - ni[X]it 15:58:52 10/03/06 That is pretty. Now that I think about it, you're pretty. (n/m) - Rage (Troll) 17:36:54 10/03/06 Re: Stop it. I wish you would stop.... - I-xclr8 20:19:11 10/03/06 eh - aliaZ 20:50:56 10/03/06 I think you missed his point - maglito 21:16:58 10/03/06 I think Ash had issues with VE being greater than 100% - The Devils Z 21:45:28 10/03/06 which data are you referring to? (n/m) - aliaZ 22:27:00 10/03/06 ok I think I see what is going on - aliaZ 23:07:32 10/03/06 I'm not sure if I know what point he was.... - I-xclr8 22:05:55 10/03/06 there is merit to testing with the upstream component in the - maglito 00:54:21 10/04/06 My biggest complaint here is the fact that I have provided - Ash's Z 00:45:25 10/04/06 do your flow testing, present your data (n/m) - maglito 01:11:04 10/04/06 LOL, that was/is the plan. :) - Ash's Z 01:37:14 10/04/06 test a dirty K&N (20k+ miles) vs it freshly cleaned/charged (n/m) - maglito 01:58:35 10/04/06 HUGE 2nd! Also stock airbox. (n/m) - CaliguyPurdue 10:49:53 10/04/06 I have nothing to gain or anything to lose in the test. - Ash's Z 00:26:44 10/04/06 Now you're just arguing semantics. - Kenny 12:06:10 10/04/06 So are you saying that every cylinder head, valve, and - Ash's Z 12:35:11 10/04/06 Of course not. - Kenny 12:53:10 10/04/06 I'm not going to pick your opinion apart. I will just fall - Ash's Z 13:19:42 10/04/06 The testing can be improved, your method would be... - Kenny 13:48:50 10/04/06 Nick, how is this any different? - Ash's Z 12:37:00 10/04/06 "how the Z1, Stillen, HKS and Greddy stack up" --> - Inzane 11:13:53 10/03/06 Well, I wont be getting the flowbench information today >>>> - Ash's Z 13:36:24 10/03/06 When you test the manifolds why not test using your - CaliguyPurdue 15:36:05 10/03/06 I appreciate the advice, Jim. I take it you are referring - Ash's Z 00:31:59 10/04/06 Yep that way I have something to compare - CaliguyPurdue 10:45:04 10/04/06
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