From Diy_Efi-Owner Thu May 5 17:43:03 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA04667; Thu, 5 May 94 17:43:03 GMT Received: from cs.utexas.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA04661; Thu, 5 May 94 13:43:01 -0400 Received: from needmore.cs.utexas.edu (haskett@needmore.cs.utexas.edu [128.83.138.122]) by cs.utexas.edu (8.6.9/8.6.9) with SMTP id MAA14512 for ; Thu, 5 May 1994 12:42:43 -0500 Received: by needmore.cs.utexas.edu (5.64/Client-v1.4) id AA12127; Thu, 5 May 94 12:42:27 -0500 Date: Thu, 5 May 1994 12:42:26 -0500 (CDT) From: Brian Scott Haskett Subject: Re: Intro ... To: DIY_EFI In-Reply-To: <9405051604.AA03454@coulomb.eng.ohio-state.edu> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu On Thu, 5 May 1994, Jeffrey S Armfield wrote: > Control algorithms are no problem. I need to know more about real time > operating systems and some of the more esoteric hardware stuff. OK- I have been thinking about this the past few weeks. I think that the best way to implement a *cheap* real-time data acquisition/control application is to do so on a DOS machine. I don't think anyone wants to hear the nitty-gritty explanation of real time, but a hard real-time system is just not economical or practical. To achieve real-time, disk i/o and user i/o (or basically anything that takes a long time) cannot be used. This rules out anything with virtual memory. So.... a nice, stripped down version of DOS with little or no TSR's would be a good platform to implement a soft real-time system, in my opinion. Just go to the local used computer store, pick up a cheap 286 laptop, and go work. The application would have to store all of its data in RAM, until it can exit real-time mode and store to / read from the disk. Of course, this is just the thinking that I have been banging around the past few weeks, and is certainly open for discussion. -Brian From Diy_Efi-Owner Thu May 5 17:58:39 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA04806; Thu, 5 May 94 17:58:39 GMT Received: from stdvax.gsfc.nasa.gov by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA04800; Thu, 5 May 94 13:58:38 -0400 Date: Thu, 5 May 1994 13:57:05 -0400 (EDT) From: OADDAB@STDVAX.GSFC.NASA.GOV (DIRK BROER) Message-Id: <940505135705.2dc04180@STDVAX.GSFC.NASA.GOV> Subject: Intro To: DIY_EFI X-Vmsmail-To: @EFI Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu My name is Dirk Broer E-mail address is OADDAB@stdvax.gsfc.nasa.gov I'm an electrical engineer working for Fairchild Space at NASA's Goddard Space Flight Center - in particular I'm working with the guidance and control group. In the 4 years I've mostly done embedded systems - mostly programming... My interests are to get a system - that may not necessarily control an engine - but that it can monitor all the aspects so that I can make better decisions on what changes to make... I have future dreams about retro fitting a an EFI system on a large displacement - turbo charged motor - the goal would be maximum hp - with manners. What I can add to the group: Programming - you pick the language, and mild electrical design - I don't have much experience with specific processors other than intel x86 and motorola 68XXX and even the 6502. I can desing and build filters, and amps etc (cookbook electronics). I have access to, and know how to use, schematic CAD, layout tools, PLD tools and people who have done just about anything else including packaging engineers (and I haven't annoyed them...yet). As for a CPU / architecture - let me propose this: A while ago I worked with a company called CUbit - they made, among other things, an 80186 based, STD Bus board. What I particularly enjoyed about their set-up is that the on board ROMs would communicate with Borland's C Remote debugger. That means you write the code on a PC (all Borland), compile and link it, and then down load it to the board - and you can step through the code running on the remote CPU. A breeze to debug. Then you link the code with a provided library and you can burn that code directly on ROM's. The 80186 board could have as much as 32K of ram, 5 counters, and 8256 Muart for serial, parralel, and interrupt control. Cost was about $170 for a bare board (no ROMS) and a high of $700 for a board, serial interface card, ROMs, Card Cage (4-5 cards), and Borland C++. Barring something like that, I would suggest the cost effective way to go is an OEM computer - that we disect. The nice thing about an OEM computer is that not only is the computer pre-built but the wiring harness etc is almost ready to use... Besides for those with the know how and the right info - you could make some money on the side reprogramming stock computers for local speed shops.... Dirk From Diy_Efi-Owner Thu May 5 18:16:17 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA04845; Thu, 5 May 94 18:16:17 GMT Received: from cs.utexas.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA04839; Thu, 5 May 94 14:16:15 -0400 Received: from needmore.cs.utexas.edu (haskett@needmore.cs.utexas.edu [128.83.138.122]) by cs.utexas.edu (8.6.9/8.6.9) with SMTP id NAA18665 for ; Thu, 5 May 1994 13:15:58 -0500 Received: by needmore.cs.utexas.edu (5.64/Client-v1.4) id AA12261; Thu, 5 May 94 13:15:28 -0500 Date: Thu, 5 May 1994 13:15:24 -0500 (CDT) From: Brian Scott Haskett Subject: Re: your mail To: DIY_EFI In-Reply-To: <199405051528.AA21311@mtu.edu> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu On Thu, 5 May 1994, Mark Shirley wrote: > For some time now, I have been kicking around an idea for a pet project of > mine. I have a 300 cubic inch straight six ford engine in a truck, and I > am considering some sort of port efi. I think I can get it to work with > a six cylinder setup off of something else. I have also been thinking of > using a paxton supercharger on this setup. Any problems I may run into? I've been thinking about doing something similar... If anyone knows what the head of a Ford 200 looks like, then you can understand why I want to ditch the single carb on my '66 stang and use port injection. The intake is basically a cast-in pipe, with holes into the combustion chambers. That's a dumb intake design, but at least by going to port injection, I could solve the problem of the fuel having to travel that horendous path (thought the air will still have to). I wouldn't want to mess up my almost-totally stock classic car, so I would do this on a junk-yard head. Just drill some holes to get a straight shot into the chambers, and weld on buses for the injectors.... Sounds good in theory to me, but I don't think a stock EFI computer will do the job on such a radical carry-over. Another thing I would have to look into is if injectors exist that would give the designed fuel spray at that distance from the intake port.... The bane of the Ford 200 is that it refuses to idle smoothly, and hopefully an EFI set-up would help out. From Diy_Efi-Owner Thu May 5 18:36:17 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA04964; Thu, 5 May 94 18:36:17 GMT Received: from oasys.dt.navy.mil by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA04957; Thu, 5 May 94 14:36:12 -0400 Received: from gallant.dt.navy.mil by oasys.dt.navy.mil (5.61/oasys.dt.navy.mil) id AA04594; Thu, 5 May 94 14:36:09 EDT Date: Thu, 5 May 94 14:36:09 EDT Message-Id: <9405051836.AA04594@oasys.dt.navy.mil> From: "Robert Gallant" To: DIY_EFI Subject: Re: Intro ... Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu OK, here's my intro.. I am a Mechanical Engineer with a fairly strong Electrical background. Currently I do acoustic research for the Dept. of Navy, this is mainly Physics (yeack!). The vehicle in need: I have a modified, second generation, Rx7. It is supercharged with a positive displacement blower to about 11 psi (currently I have the 8 psi pulley on). Right now it has a Holley ProJection (AAAAAAAAhhhhhh). Sorry, that happens every time ProJection gets mentioned (I'll try to control myself). But you all know about the ProJection. I will be getting a beta test version of the new ProJection Computer in mid June. If it is as good as the original, I'll be in the market to build my own. Rob gallant@oasys.dt.navy.mil From Diy_Efi-Owner Thu May 5 18:45:56 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA05008; Thu, 5 May 94 18:45:56 GMT Received: from stdvax.gsfc.nasa.gov by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA05002; Thu, 5 May 94 14:45:54 -0400 Date: Thu, 5 May 1994 14:44:23 -0400 (EDT) From: OADDAB@STDVAX.GSFC.NASA.GOV (DIRK BROER) Message-Id: <940505144423.2dc04180@STDVAX.GSFC.NASA.GOV> Subject: Some thoughts and questions on EFI To: DIY_EFI X-Vmsmail-To: @EFI Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu Before we decide on what computer to use etc shouldn't we decide what the operating enviroment or rather the requirements are? Ouput would be a PWM signal to the injectors. You could vary the start time and the end time of each injector to get sequential port injection. For input I suspect we'd need: O2 sensor - what better way to set the car for part throttle cruise. Throttle Position sensor temperature sensor RPM sensor - maybe an engine position sensor - so you know exactly which cylinder needs fuel / spark next (distributer mounted of course). and then either a MAP or MAF sensor. maybe Humidity sensor? - or altimeter? Is that all? If that is all perhaps we could also get an idea on what kinda of data rates are needed. 02 sensors react relatively slow - maybe 10 readings a sec? TPS - sensors - at least 10 readings a second if not more Temp sensors - 1 reading a second RPM sensor - at 10,000rpm (why not?) - that 600,000 degrees per second. 4 bumps on the crank shaft (ie - crank triggered ignition) would mean less than 1000 per second... MAP or MAF sensor - 1 per second - maybe more... 10? The system would have to work at: Startup Idle part throotle cruise WOT anything else? Next post what would the algorithm be like? Dirk From Diy_Efi-Owner Thu May 5 18:46:04 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA05016; Thu, 5 May 94 18:46:04 GMT Received: from wotan.compaq.com by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA05010; Thu, 5 May 94 14:46:03 -0400 Received: from twisto.eng.hou.compaq.com by wotan.compaq.com with smtp (Smail3.1.28.1 #6) id m0pz8Nt-0002gdC; Thu, 5 May 94 13:42 CDT Received: from bangate.compaq.com by twisto.eng.hou.compaq.com with smtp (Smail3.1.28.1 #8) id m0pz8Nt-000piUC; Thu, 5 May 94 13:42 CDT Message-Id: Received: by bangate.compaq.com with VINES ; Thu, 5 May 94 13:43:01 CDT Date: Thu, 5 May 94 11:40:47 CDT From: Steve=Ravet%Prj=Eng%PCPD=Hou@bangate.compaq.com Subject: jai To: diy_efi Cc: Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu just another intro.... I am a recent graduate of Texas A&M University. I greatly enjoyed my 8 years there, but the bills piled a little too high so I had to get a real job. :-( I received my undergraduate in May 91 in electrical engineering. I immediately started graduate school, in electromagnetics (silly, silly me). After some time, the realization that I really didn't like electromagnetics, and what's more, there really aren't any jobs in the field, sunk in. So I switched to digital/computer architecture. I will graduate in May, and I have been working at Compaq since February. My graduate work involved the GPS (global positioning system) as it relates to real time navigation in a car. I would like to make a suggestion: I think the topic of electronically controlled ignitions fits in well with efi, and would like to see that topic covered here as well (mostly because that's the first thing I would like to add to my car). Please no flames, but perhaps a yea or nay response to see what the general consensus is. I think a CPU that should be considered is the Dallas Semiconductor DS5000. I include here a snippet of information that appeared on alt.hotrod (which means that most of you have already seen it, i guess. oh well). In article <1gc6-pr@dixie.com> hotrod@dixie.com writes: >[The EFI system is pretty simple. A dallas semi DS5000 hybrid supplies >all the smarts. This is a pretty amazing part. It contains an >8052-like processor, ram, "rom" (battery-backed ram), timers, watchdog >timer and some other goodies in a double height 40 pin dip. It has >3 8 bit I/O ports and a serial port. Best of all, you program it >by jinking several pins during power up and then pumping intel HEX >records into the serial port. when the END record is received, >the chip reboots and starts running the program as if it were in >ROM. The main advantage I see here is that no eprom programmer is required. In fact, if you have a laptop of some sort, you can compile/reprogram without ever leaving the car. The built-in I/O ports are nice too. And there are plenty of 8052 compilers/assemblers out there. One more thing, not to stifle creativity, but I think we should come up with a "list project". That is, after _plenty_ of discussion, we should decide on what the capabilities of the system should be, what type of CPU to use, etc. The hardware should be generic enough to handle various engine configurations and other mods people want to make that aren't part of the "list project". Discussion would *not* be limited to just the list project, but if most people work on the same thing, we will make the most progress. For now, we should pool our knowledge. I have little knowledge of engines in general, but I can breadboard and program embedded systems. Perhaps people who have extensive knowledge of efi (and electronic ignition systems) could write a tutorial on theory and post it. Anyway, looking back, I'm afraid I'm becoming long winded, or worse, trivial, so I will end. Looking forward to some good info. --steve sravet@bangate.compaq.com From Diy_Efi-Owner Thu May 5 18:51:28 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA05042; Thu, 5 May 94 18:51:28 GMT Received: from oucsace.cs.ohiou.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA05036; Thu, 5 May 94 14:51:27 -0400 Received: (from dstudly@localhost) by oucsace.cs.ohiou.edu (8.6.8/8.6.6) id OAA17591 for DIY_EFI@coulomb.eng.ohio-state.edu; Thu, 5 May 1994 14:51:25 -0400 From: David Studly Message-Id: <199405051851.OAA17591@oucsace.cs.ohiou.edu> Subject: Intro To: DIY_EFI Date: Thu, 5 May 1994 14:51:24 -0400 (EDT) X-Mailer: ELM [version 2.4 PL22] Content-Type: text Content-Length: 1001 Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu Well, since introductions seem to be the way to go, here's mine. I'm a CS major at Ohio University. I do not have any background with building any electronic devices, nor am I a great programmer - maybe just lack of experience. I suppose you could say I am 'handy' with computers, but from some of the other intros I've seen in the group, I am at or a below a beginner's level! Anyway, I do have a strong understanding of engine performance, and I understand the basic operation of EFI systems in production cars. The advantages of EFI have always fascinated me. I built my '70 Chevelle from a 16-second ho-hummer, into a streetable, comfortable, 12-second cruiser. I also autocross my daily-driven '88 Cavalier in SCCA H-Stock. As far as platforms go, I would prefer something I can do on either an x86 laptop, or something based on a production car computer, for cost reasons. I mostly plan on just reading this list, to see what I can learn. -David Studly, dstudly@oucsace.cs.ohiou.edu From Diy_Efi-Owner Thu May 5 19:14:10 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA05092; Thu, 5 May 94 19:14:10 GMT Received: from oasys.dt.navy.mil by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA05085; Thu, 5 May 94 15:14:05 -0400 Received: from gallant.dt.navy.mil by oasys.dt.navy.mil (5.61/oasys.dt.navy.mil) id AA10914; Thu, 5 May 94 15:14:02 EDT Date: Thu, 5 May 94 15:14:02 EDT Message-Id: <9405051914.AA10914@oasys.dt.navy.mil> From: "Robert Gallant" To: DIY_EFI Subject: Re: Some thoughts and questions on EFI Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu > 02 sensors react relatively slow - maybe 10 readings a sec? > TPS - sensors - at least 10 readings a second if not more > Temp sensors - 1 reading a second > RPM sensor - at 10,000rpm (why not?) - that 600,000 degrees per second. 4 > bumps on the crank shaft (ie - crank triggered ignition) would mean less > than 1000 per second... > MAP or MAF sensor - 1 per second - maybe more... 10? For temp, intake air temp would also be good. > The system would have to work at: > Startup > Idle > part throotle cruise > WOT > anything else? How about deceleration fuel cut. Also, I tune WOT/full boost by exhaust temperature. It would be slick to add this to the system. But maybe I'm getting too much into what I need for my exact application. Rob gallant@oasys.dt.navy.mil From Diy_Efi-Owner Thu May 5 19:28:29 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA05127; Thu, 5 May 94 19:28:29 GMT Received: from hp-cv.cv.hp.com by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA05121; Thu, 5 May 94 15:28:18 -0400 Received: from hp-pcd.cv.hp.com by hp-cv.cv.hp.com with SMTP (1.36.108.7/15.5+IOS 3.22+CV 1.0ext) id AA19642; Thu, 5 May 1994 12:28:16 -0700 Received: from by hp-pcd.cv.hp.com with SMTP (1.37.109.8/15.5+IOS 3.22+OM+CV 1.0) id AA15419; Thu, 5 May 1994 12:28:15 -0700 From: cary_mccallister@hp-corvallis.om.hp.com X-Openmail-Hops: 2 Date: Thu, 5 May 94 12:26:54 -0700 Message-Id: In-Reply-To: <9405051914.AA10914@oasys.dt.navy.mil> Subject: Re: Some thoughts and questions on EFI Cc: DIY_EFI Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu ______________________________ Reply Separator _________________________________ Subject: Re: Some thoughts and questions on EFI Author: Non-HP-Diy-Efi-Owner (Diy_Efi-Owner@coulomb.eng.ohio-state.edu) at HP-Corvallis,unix1 Date: 5/5/94 12:14 PM > 02 sensors react relatively slow - maybe 10 readings a sec? > TPS - sensors - at least 10 readings a second if not more > Temp sensors - 1 reading a second > RPM sensor - at 10,000rpm (why not?) - that 600,000 degrees per second. 4 > bumps on the crank shaft (ie - crank triggered ignition) would mean less > than 1000 per second... > MAP or MAF sensor - 1 per second - maybe more... 10? For temp, intake air temp would also be good. > The system would have to work at: > Startup > Idle > part throotle cruise > WOT > anything else? How about deceleration fuel cut. *************************************************************************** One thing I have noticed that has been missed so far is battery voltage. You need to measure this to correct the pulse width sent to the injector. Perhaps there are some new injector driver circuits out there that do this? I have been using the MC 3334 form Motorola. My experiments so far are probably a little crude to what I have read. I have been using a PC parallel port connected to a A/D converter and then used a lookup table to calculate the pulse width. To date the system has idled the car, but fails to accelerate properly ( engine stumbles and dies ). Cary McCallister cmcalstr@hpcvts.cv.hp.com From Diy_Efi-Owner Thu May 5 20:11:36 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA05250; Thu, 5 May 94 20:11:36 GMT Received: from knuth.mtsu.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI@coulomb.eng.ohio-state.edu diy_efi-outgoing id AA05244; Thu, 5 May 94 16:11:23 -0400 Received: by knuth.mtsu.edu (Smail3.1.28.1 #17) id m0pz9lg-000AVPC; Thu, 5 May 94 15:11 CDT Message-Id: From: lusky@knuth.mtsu.edu (Jonathan R. Lusky) Subject: Re: Some thoughts and questions on EFI To: DIY_EFI Date: Thu, 5 May 1994 15:11:36 -0500 (CDT) In-Reply-To: <9405051914.AA10914@oasys.dt.navy.mil> from "Robert Gallant" at May 5, 94 03:14:02 pm X-Mailer: ELM [version 2.4 PL23] Content-Type: text Content-Length: 779 Sender: Diy_Efi-Owner Precedence: bulk Reply-To: DIY_EFI@coulomb.eng.ohio-state.edu Robert Gallant writes: > How about deceleration fuel cut. Idle air control (IAC) would be nice, too. Good IAC can really smooth out a big cam at idle. In case anyone hasn't seen it before (i've seen it posted to r.a.t), this is the basic equation GM uses for its speed density systems: OT = (BPC * F/A * VE * BLC * DFCO * DE)/2 + AE where OT = Injector On Time BPC = Base pulse constant F/A = 1/(desired AF ratio) VE = Volumetric efficiency BLC = Block learn multiplier/128 DFCO = Deceleration fuel cutoff DE = Deceleration enleanment AE = Acceleration enrichment -- Jonathan R. Lusky -- lusky@knuth.mtsu.edu "Turbos are nice but I'd rather be blown!" 89 Jeep Wrangler - 258 / pile of junk! 80 Toyota Celica - 20R / 5spd