DIY_EFI Digest Thursday, October 21 1999 Volume 04 : Number 594 In this issue: Re: DIY_EFI Digest V4 #593 EPROM Programmer? Re: DIY_EFI Digest V4 #593 Are Honda VTEC turbo Re: DIY_EFI Digest V4 #592 ecu files New Fuel System Plans See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- Date: Thu, 21 Oct 1999 06:35:21 -0500 From: nacelp@xxx.com (CSH-HQ) Subject: Re: DIY_EFI Digest V4 #593 Holley is not rating the CFM of it's TBI's by airflow, as strange as that might seem. They are using a comparitive rating of the injector size supplied to average jetting used per carb. I don't have the exact numbers here but like they have 3 TB's all with the same butterflies,, but rate them as 650 w/45 lb/hr injectors, 750 has 55's, and the 900 80-90's. All I can say with absolute certainty is that for me, a 355 224@xxx.050 cam, 9.0:1 CR 3000lb car, with gears and converter luvs 2 (2") butterflies, and 2 90lb/hr injectors.. Grumpy >> >> Watch out for the flow on things like Holley Pro-Jection. 2 barrel carbs >> are rated for flow (in cfm) at 3 inches of Hg pressure drop. 4 barrel carbs >> are rated for flow at 1.5 in. Hg pressure drop--NOBODY seems to publish the >> pressure drop at which things like pro-jection are flow rated---BUT--I have >> talked to folks who have tried the pro-jection, and found, by >> experience--their engine does _ NOT _ flow nearly as well as with a 4 >> barrel of similar flow rating--that Holley must be rating the projection >> units at some (unknown) higher pressure drop!!! >> >> (Just for general info, the multiplier for comparing 2 barrel carbs to 4 >> barrels is .707. A 350 cfm rated 2 barrel only flows 247.5 cfm if rated >> using the same test conditions which are used for rating a 4 barrel!) >> >> Regards, Greg > >Thanks Greg...I had completely forgotten that fact...quite right you are! > ------------------------------ Date: Thu, 21 Oct 1999 09:06:22 -0400 From: "Stephen R. Cauffiel" Subject: EPROM Programmer? Hey fellas, I own a 1988 Trans Am that I am dropping a 383 into. It has a 305 with TBI currently and I want to learn how to modify/burn my own chips in order to keep using the TBI setup. I think the TBI system could be made to support serious horsepower (using a 454 setup perhaps), I just need to learn more on this whole programming thing. Doing it on the cheap would be nice, too. I was looking on E-Bay for EPROM burners/programmers but I'm not sure what I need to be looking for. If anyone can point me in the right direction I would appreciate it: type of burner, type of chips, books that I can get a real start in, etc.. A "Car Chips Computer Programming for Dummies" would be nice. I have been lurking on this list for quite a while, but a lot of it is still greek to me (even with a computer programming background) so any help would be appreciated! Steve "Only two things are infinite, the universe and human stupidity, and I'm not sure about the former." ~Albert Einstein~ ------------------------------ Date: Thu, 21 Oct 1999 09:54:45 -0400 From: "Gary Derian" Subject: Re: DIY_EFI Digest V4 #593 The flow capacity of things like throttle bodies or carburetors cannot be considered a single number. The number is OK for comparison purposes but should not be thought of as some kind of limit. These things will flow more at a higher pressure drop, less at a lower one. A gasoline engine consumes close to 140 cfm for every 100 hp. A 400 hp engine therefore consumes 560 actual cfm. A device rated at 650 cfm at 1.5 in. Hg will have a pressure drop of (560/650)^2*1.5 or 1.1 in. Hg. If you want less restriction, a 750 rated device will have only 0.84 in. Hg pressure drop on a 400 hp engine. The flow ratings are merely a point on a curve. Gary Derian > > >Currently my engine only consumes somewhere around 625 cfm max...I believe > > >that the BB TBI's flow 670 cfm so I too have thought about a BB TBI...Holley > > >makes a SB TBI manifold good for 6000 rpm as well...I'll have to check it's > > >height though? ------------------------------ Date: Thu, 21 Oct 1999 18:53:08 +0200 From: =?iso-8859-1?Q?J=F6rgen_Karlsson?= Subject: Are Honda VTEC turbo A friend is installing a turbo in a Honda Civic with a B16A VTEC engine. I am going to build an additional injector controller for it. An aftermarket engine management system will be installed later on. I will try to trigger a multivibrator from the rising flank of stock injectors and I need to know if the engine uses sequencial injection or batch fire. I hope to save some time if any of you guys know this since I can't put my hands on the car until sunday. Should I expect large voltage peaks when the injectors close? Jörgen Karlsson Gothenburg, Sweden ------------------------------ Date: Thu, 21 Oct 1999 11:55:25 -0600 From: "Al Jurenas" Subject: Re: DIY_EFI Digest V4 #592 | From what I can tell, the ECM (on a 90 GM) keeps track of the IAC position by remembering how many pulses it has sent out. This count shows up on a scanner. I believe the ECM reseats the IAC pindle (sends out multiple pulses to bring it all the way in or out) every time: (a) The battery power is removed and reapplied (b) you put the ECM in diagnostic mode by grounding at the ALDL connector, and (c) The car is driven at over 20 mph. By doing this, the ECM knows what position the IAC is, and recalibrates the IAC position by resetting the pulse count. | Date: Wed, 20 Oct 1999 13:32:04 +0100 | From: Ade + Lamb Chop | Subject: Re: DIY_EFI Digest V4 #590 | | At 15:00 19/10/99 -0400, DIY_EFI Digest wrote: | > | >Date: Tue, 19 Oct 1999 07:53:07 PDT | >From: "Gary Moulton" | >Subject: Manual control of IAC motor | > | >Can someone tell me which terminals of the IAC motor runs the pintle in and | >out? The wiring diagrams show two coils and the connector has 4 terminals. | >Does one coil send the position back to the ecm and the other is a 12 volt | >reversable dc motor? | > | >Application is 1994 Mopar 4.0L EFI in a 1982 Jeep CJ-7, and what I want to | >do is be able to manually adjust the idle lower than the 750-800 rpm when | >off-roading. I have connectors and a harness and some electrical experience. | >I plan to have a switch to disconnect the IAC from the system for manual | >control and a spring loaded switch to "bump" the IAC position in or out. | >There is a company offering such a controller for more money than I think it | >should cost to build one myself. Thanks in advance | | I don't know about your system but the mini one IAC is a stepper motor. You | need a driver to run it. The motors I have seen have a permanant magnet on | the spindle then the driver powers coils to step the field round. I am | supprised it doesn't have any feed back of where it is though. I suppose | the ECU gets it to the right place by trial and error. Then resets it's | self back to a postion where startup is good. | | There are loads of driver chips around cannot think of on off hand. There | are 2 different sorts of motor too 4 and 6 wire ones... cannot remember | what yours is called tho. | | HTH, | | Ade | | ------------------------------ Date: Thu, 21 Oct 1999 13:58:56 -0400 From: Mike Rolica Subject: ecu files Has anyone worked on or are currently working on a ecu file for promedit/winbin for a 165 ecm?. Or an even better idea :-), does anyone out there have a ecu file already? Can I create a ecu file?, If I can, what do I need to know? (no smart donkey comments please :-).) Mike Rolica EXT. 260 :-) ------------------------------ Date: Thu, 21 Oct 1999 14:19:38 -0400 From: "Bob Colvin" Subject: New Fuel System Plans This is a multi-part message in MIME format. - ------=_NextPart_000_0030_01BF1BCF.4EF62E40 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable http://www.friend.ly.net/GEET/plans.htm =20 - ------=_NextPart_000_0030_01BF1BCF.4EF62E40 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
http://www.friend.ly.net= /GEET/plans.htm
 
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