From owner-diy_efi Wed Aug 3 16:38:22 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA04712; Wed, 3 Aug 94 16:38:22 GMT Received: from us.dynix.com by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA04707; Wed, 3 Aug 94 12:38:19 -0400 Received: from cpu.us.dynix.com by dnxjcit.us.dynix.com with SMTP id AA22795 (5.65c/IDA-1.4.4 for ); Wed, 3 Aug 1994 10:41:02 -0600 Received: by cpu.us.dynix.com (AIX 3.2/UCB 5.64/4.03) id AA72534; Wed, 3 Aug 1994 10:37:47 -0600 Date: Wed, 3 Aug 1994 10:36:01 -700 (MDT) From: Jim Conforti Subject: Re: VW Digifant To: Jens Knickmeyer Cc: DIY_EFI In-Reply-To: <9408031303.AA18864@diana> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI On Wed, 3 Aug 1994, Jens Knickmeyer wrote: > - The Digifant stores injection/ignition data in a 27C512 EPROM chip. > 1. How are these data organized? > 2. How do I have to change EPROM data after tuning the mechanical > G-compressor used in the G-40/G-60 ? If you can get a copy of the EPROM data posted on the net .. (in HEX format) .. or make it available via FTP .. I'll take a look at it and see if I can help .. My partner and I have quite a bit of Experience with BOSCH Motronic systems Jim Conforti From owner-diy_efi Wed Aug 3 19:18:14 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA05121; Wed, 3 Aug 94 19:18:14 GMT Received: from localhost.eng.ohio-state.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA05100; Wed, 3 Aug 94 15:18:11 -0400 Message-Id: <9408031918.AA05100@coulomb.eng.ohio-state.edu> To: DIY_EFI Subject: Admin regarding: Re: VW Digifant In-Reply-To: Your message of "Wed, 03 Aug 94 10:36:01." Date: Wed, 03 Aug 94 15:18:11 -0400 From: John S Gwynne Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI -------- In message , you writ e: | | | On Wed, 3 Aug 1994, Jens Knickmeyer wrote: | | > - The Digifant stores injection/ignition data in a 27C512 EPROM chip. | > 1. How are these data organized? | > 2. How do I have to change EPROM data after tuning the mechanical | > G-compressor used in the G-40/G-60 ? | | If you can get a copy of the EPROM data posted on the net .. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Lets be careful not to blatantly violate any copyright laws. I would like to encourage the discussion of such codes over this mailing list, but I must discourage its dissemination. #ifndef BigBrother #include #endif I'm looking forward to writing the DIY_EFI software which will not have such restrictions. John S Gwynne Gwynne.1@osu.edu _______________________________________________________________________________ T h e O h i o - S t a t e U n i v e r s i t y ElectroScience Laboratory, 1320 Kinnear Road, Columbus, Ohio 43212, USA Telephone: (614) 292-7981 * Fax: (614) 292-7292 ------------------------------------------------------------------------------- From owner-diy_efi Wed Aug 3 20:01:35 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA05315; Wed, 3 Aug 94 20:01:35 GMT Received: from localhost.eng.ohio-state.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA05310; Wed, 3 Aug 94 16:01:33 -0400 Message-Id: <9408032001.AA05310@coulomb.eng.ohio-state.edu> To: DIY_EFI Subject: Project update Date: Wed, 03 Aug 94 16:01:33 -0400 From: John S Gwynne Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI -------- HARDWARE Currently: I hope to have to the 68HC000 debugged and running by late September. I now have all the parts for the main board and am in the process of wire-wrapping the proto-type. Latter (more expensive) versions will probably switch to something in the CPU32 family. Next: I intend to digitize sensor data (i.e., MAP, RPM, ...) and look at their spectral content to determine sampling rates. If others have similar data please share it with us. SOFTWARE - Can we come up with a means of calibrating the fuel map of a speed/density system without the use of a dynamometer? - Dale Ulan posted several weeks ago with regards to Acceleration Enrichment: "Ideally, you would model the fuel thickness in the intake manifold between the injector and valve, which would require air temp, manifold temp, manifold vacuum/pressure, and probably an estimation of the willingness of the air to accept the gasoline as a vapour. This is something for someone who has done research on this area... if you can model it, you don't have to spend as much time tuning..." Is anyone familiar with related research in this area? Is there someone with this experience that we may be able to recruit and have answer a few questions? I'm willing to take a guess at some means of controlling the acceleration enrichment, but it would be helpful (and maybe even interesting) to see it related to theory. Your comments are appreciated. John S Gwynne Gwynne.1@osu.edu _______________________________________________________________________________ T h e O h i o - S t a t e U n i v e r s i t y ElectroScience Laboratory, 1320 Kinnear Road, Columbus, Ohio 43212, USA Telephone: (614) 292-7981 * Fax: (614) 292-7292 ------------------------------------------------------------------------------- From owner-diy_efi Wed Aug 3 21:08:28 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA05519; Wed, 3 Aug 94 21:08:28 GMT Received: from gw1.att.com by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA05512; Wed, 3 Aug 94 17:08:25 -0400 Received: from uscbu.ih.att.com by ig1.att.att.com id AA08228; Wed, 3 Aug 94 17:03:46 EDT Received: by uscbu.ih.att.com (4.1/EMS-1.0.2 main.cf 1.37 10/5/93 (SMI-4.1/SVR4)) id AA12621; Wed, 3 Aug 94 16:04:21 CDT From: Bohdan.L.Bodnar@att.com Received: from usgp1.ih.att.com by uscbu.ih.att.com (4.1/EMS-1.0.2 main.cf 1.37 10/5/93 (SMI-4.1/SVR4)) id AA12617; Wed, 3 Aug 94 16:04:20 CDT Received: by usgp1.ih.att.com (5.0/EMS-1.1 client.cf 1/8/94 (SMI-4.1/SVR4)) id AA25518; Wed, 3 Aug 1994 16:04:19 +0600 Date: Wed, 3 Aug 1994 16:04:19 +0600 Message-Id: <9408032104.AA25518@usgp1.ih.att.com> Original-From: bohdan@uscbu.ih.att.com (Bohdan L Bodnar) To: DIY_EFI Subject: Re: Project update Content-Type: text Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI Regarding sampling rates and acceleration enrichment: Most sensors are sampled 10x/second on contemporary stock vehicles. This rate is chosen so as to make the operation "real-time" and so as not to overload the cpu in the computer (keep in mind that up until a few years ago, most cpus were 8 bit machines). "Much faster" sampling will require, other than a faster cpu, low-pass filtering before any ADCs (i.e., the "anti-aliasing" filters). On acceleration (and decel): Fuel injector firing consists of two types: synchronous and asynchronous. Synchronous firing occurs in step with a sync signal (e.g., coming off of the distributor's reference line) whereas asynchronous is triggered by rapid changes in the throttle position sensor. Asynchronous firing will occur during acceleration AND deceleration. To the best of my knowledge, most of the work that you desire to do is done empirically. SAE had a publication (1992) whose name escapes me right now which dealt with engine transducers and had some NEAT stuff on experimental adaptive engine controls. If there's enough interest, I can dig it up. Cordially, Bohdan Bodnar bohdan.l.bodnar@att.com From owner-diy_efi Thu Aug 4 01:36:59 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA06136; Thu, 4 Aug 94 01:36:59 GMT Received: from pine.cse.nau.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA06131; Wed, 3 Aug 94 21:36:56 -0400 Received: (from met@localhost) by pine.cse.nau.edu (8.6.9/2.2-nau) id SAA29250 for DIY_EFI@coulomb.eng.ohio-state.edu; Wed, 3 Aug 1994 18:36:50 -0700 Message-Id: <199408040136.SAA29250@pine.cse.nau.edu> From: met@pine.cse.nau.edu (MTN-KAT) Date: Wed, 3 Aug 1994 18:36:50 -0700 In-Reply-To: Bohdan.L.Bodnar@att.com "Re: Project update" (Aug 3, 4:04pm) X-Mailer: Mail User's Shell (7.2.5 10/14/92) To: DIY_EFI Subject: Re: Project update Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI I'm interested in the SAE paper that you mention, please do dig it up and post. MIllam / From owner-diy_efi Thu Aug 4 02:02:25 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA06171; Thu, 4 Aug 94 02:02:25 GMT Received: from localhost.eng.ohio-state.edu by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA06165; Wed, 3 Aug 94 22:02:23 -0400 Message-Id: <9408040202.AA06165@coulomb.eng.ohio-state.edu> To: DIY_EFI Subject: Re: Project update In-Reply-To: Your message of "Wed, 03 Aug 94 16:04:19 +0600." <9408032104.AA25518@usgp1.ih.att.com> Date: Wed, 03 Aug 94 22:02:22 -0400 From: John S Gwynne Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI -------- In message <9408032104.AA25518@usgp1.ih.att.com> , you write: | Regarding sampling rates and acceleration enrichment: | | Most sensors are sampled 10x/second on contemporary stock vehicles. This It would seem to me (and I have not measured this yet) that the period of greatest MAP variation would be during starting. A period when the crank rotation itself may not even be very smooth. I would guess, again without any supporting data, that fuel metering is the most difficult to accomplish during starting. 10x/sec would seem slow to me to track the variations. Maybe not... hopefully by October I will have some data to share with the group. The little 80C85 based laptop computer that I have been using will not sample fast enough in basic without going to machine language to measure this. I've decided to stay focused on finishing the 68HC000 and use that to acquire preliminary engine data. | On acceleration (and decel): | during acceleration AND deceleration. To the best of my knowledge, most of | the work that you desire to do is done empirically. I would not be surprised... | SAE had a publication | (1992) whose name escapes me right now which dealt with engine transducers and | had some NEAT stuff on experimental adaptive engine controls. If there's | enough interest, I can dig it up. Enough interest... are you joking? :) | Cordially, | | Bohdan Bodnar | bohdan.l.bodnar@att.com John S Gwynne Gwynne.1@osu.edu _______________________________________________________________________________ T h e O h i o - S t a t e U n i v e r s i t y ElectroScience Laboratory, 1320 Kinnear Road, Columbus, Ohio 43212, USA Telephone: (614) 292-7981 * Fax: (614) 292-7292 ------------------------------------------------------------------------------- From owner-diy_efi Thu Aug 4 14:25:56 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA07264; Thu, 4 Aug 94 14:25:56 GMT Received: from gw1.att.com by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA07259; Thu, 4 Aug 94 10:25:53 -0400 Received: from uscbu.ih.att.com by ig1.att.att.com id AA13983; Thu, 4 Aug 94 10:22:22 EDT Received: by uscbu.ih.att.com (4.1/EMS-1.0.2 main.cf 1.37 10/5/93 (SMI-4.1/SVR4)) id AA26289; Thu, 4 Aug 94 09:22:58 CDT From: Bohdan.L.Bodnar@att.com Received: from usgp1.ih.att.com by uscbu.ih.att.com (4.1/EMS-1.0.2 main.cf 1.37 10/5/93 (SMI-4.1/SVR4)) id AA26277; Thu, 4 Aug 94 09:22:57 CDT Received: by usgp1.ih.att.com (5.0/EMS-1.1 client.cf 1/8/94 (SMI-4.1/SVR4)) id AA02790; Thu, 4 Aug 1994 09:22:55 +0600 Date: Thu, 4 Aug 1994 09:22:55 +0600 Message-Id: <9408041422.AA02790@usgp1.ih.att.com> Original-From: bohdan@uscbu.ih.att.com (Bohdan L Bodnar) To: DIY_EFI Subject: Re: Project update Content-Type: text Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI Try the following: ELECTRONIC CONTROLS AND SENSORS, proceedings of the SAE International Congress and Exposition (1992: Detroit, MI). ISBN 1-56091-215-4. This book is 120 pages long. Unfortunately, I do not have it (yet) as it is in an ATT library in NJ whereas I'm in IL! If you choose to purchase it, the ISBN and title should be sufficient for a bookstore to track it down. I recall this book has some articles on nifty research done in universities in Europe on adaptive controls and some stuff on a truly exotic oxygen sensor which allows more than bang-bang control of the a/f mixture. I'm not convinced that cold start enrichment is so difficult to achieve in an EFI engine. A *lot* of multipoint injected engines in the 1980s (and earlier) used nothing more than a cold start injector which would fire for a few seconds when the ignition key was placed in "run." This injector is controlled by nothing more than a thermo-time switch -- essentially, an expensive electrically/coolant heated thermostat. If you *really* want to model this stuff, you'll need data on flow characteristics of your injectors, incoming air flow (easy to pull off if you have a MAF sensor and know the relationship between output voltage or frequency and air flow), and desired a/f ratio. The flow characteristics you can probably obtain empirically via a graduated cylinder, knowing the firing time of the injector, and knowing the fuel line pressure relative to (air) pressure seen at the injector's tip. This way, you can plot fuel delivery vs. injector on time. There are, without a doubt, a whole bunch of other things you'd have to figure out (e.g., a/f mixture vs. engine temperature...). I think I'll stick to designing computer systems... Cordially, Bohdan Bodnar bohdan.l.bodnar@att.com From owner-diy_efi Thu Aug 4 16:26:51 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA07646; Thu, 4 Aug 94 16:26:51 GMT Received: from us.dynix.com by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA07641; Thu, 4 Aug 94 12:26:48 -0400 Received: from cpu.us.dynix.com by dnxjcit.us.dynix.com with SMTP id AA28985 (5.65c/IDA-1.4.4 for ); Thu, 4 Aug 1994 10:29:36 -0600 Received: by cpu.us.dynix.com (AIX 3.2/UCB 5.64/4.03) id AA26816; Thu, 4 Aug 1994 10:26:22 -0600 Date: Thu, 4 Aug 1994 10:24:18 -700 (MDT) From: Jim Conforti Subject: Load or MAP at startup ... To: DIY_EFI In-Reply-To: <9408040202.AA06165@coulomb.eng.ohio-state.edu> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI Best way to handle the MAP fluctuations at idle, is to use a CONSTANT value for MAP until the engine is running over X rpms (X = just below idle a bit) You may get this from a 2D speed dependent table if necessary Jim Conforti From owner-diy_efi Thu Aug 4 16:30:47 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA07663; Thu, 4 Aug 94 16:30:47 GMT Received: from us.dynix.com by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA07658; Thu, 4 Aug 94 12:30:43 -0400 Received: from cpu.us.dynix.com by dnxjcit.us.dynix.com with SMTP id AA29013 (5.65c/IDA-1.4.4 for ); Thu, 4 Aug 1994 10:33:31 -0600 Received: by cpu.us.dynix.com (AIX 3.2/UCB 5.64/4.03) id AA67455; Thu, 4 Aug 1994 10:30:18 -0600 Date: Thu, 4 Aug 1994 10:26:48 -700 (MDT) From: Jim Conforti Subject: Cold start enrichment .. To: DIY_EFI In-Reply-To: <9408041422.AA02790@usgp1.ih.att.com> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI The cold start enrichment is done in phases ... 1) Start phase .. mucho fuel for 5 to 10 revs of the engine .. 2) Post start enrichment lasting a few tens of seconds or so 3) Warmup enrichment .. until engine is at running temp .. Warmup usually has two tables .. one based on engine temp, and one based on speed, MAP ... the final number is a multiplicand of the two ... Eng. temp .. more enrichment at lower engine temps .. Speed, MAP .. less enrichment at higher speeds and MAPS .. Hope this helps .. Jim From owner-diy_efi Fri Aug 5 05:07:50 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA09443; Fri, 5 Aug 94 05:07:50 GMT Received: from aztec.al.bldrdoc.gov by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA09438; Fri, 5 Aug 94 01:07:45 -0400 Message-Id: <9408050507.AA09438@coulomb.eng.ohio-state.edu> Date: 4 Aug 1994 23:13:03 U From: "Ciciora Steve" Subject: Timing Rule of thumb To: DIY_EFI Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI Just read a rule of thumb in hot rod mag. Something like "Spark susceptibility to knock increases 1 deg. for every 10 deg. increase in coolent temp." What this means to me if I ever get my ignition controller finished is I'll retard my timing 1 deg. for every 10 deg. the coolent temp. is over an (adjustable) setpoint. This setpoint will be the normal coolent operating temperature of my car. Sound good to you guys? - Steven Ciciora From owner-diy_efi Fri Aug 5 12:35:19 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA10361; Fri, 5 Aug 94 12:35:19 GMT Received: from gw1.att.com by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA10354; Fri, 5 Aug 94 08:35:16 -0400 Received: from uscbu.ih.att.com by ig1.att.att.com id AA04279; Fri, 5 Aug 94 08:34:27 EDT Received: by uscbu.ih.att.com (4.1/EMS-1.0.2 main.cf 1.37 10/5/93 (SMI-4.1/SVR4)) id AA17986; Fri, 5 Aug 94 07:35:04 CDT From: Bohdan.L.Bodnar@att.com Received: from usgp1.ih.att.com by uscbu.ih.att.com (4.1/EMS-1.0.2 main.cf 1.37 10/5/93 (SMI-4.1/SVR4)) id AA17971; Fri, 5 Aug 94 07:35:02 CDT Received: by usgp1.ih.att.com (5.0/EMS-1.1 client.cf 1/8/94 (SMI-4.1/SVR4)) id AA25724; Fri, 5 Aug 1994 07:35:00 +0600 Date: Fri, 5 Aug 1994 07:35:00 +0600 Message-Id: <9408051235.AA25724@usgp1.ih.att.com> Original-From: bohdan@uscbu.ih.att.com (Bohdan L Bodnar) To: DIY_EFI Subject: Re: Timing Rule of thumb Content-Type: text Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI I never read or heard about this rule-of-thumb. I do know that knock will depend on: 1). coolant temperature 2). incoming air temperature 3). a/f ratio 4). EGR flow 5). fuel's octane rating 6). combustion chamber design (e.g., swirl-head design is less susceptible to knock than other designs) 7). valve overlap As an aside, what temperature scale was used? Have a nice weekend! BB From owner-diy_efi Fri Aug 5 15:25:56 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA10804; Fri, 5 Aug 94 15:25:56 GMT Received: from [192.150.149.1] by coulomb.eng.ohio-state.edu via SMTP (920330.SGI/920502.SGI) for /usr/local/mail/majordomo-1.92/wrapper resend -p bulk -M 10000 -l Diy_Efi -f Diy_Efi-Owner -h coulomb.eng.ohio-state.edu -s -r DIY_EFI diy_efi-outgoing id AA10799; Fri, 5 Aug 94 11:25:53 -0400 Received: from cpu.us.dynix.com by dnxjcit.us.dynix.com with SMTP id AA04544 (5.65c/IDA-1.4.4 for ); Fri, 5 Aug 1994 09:27:58 -0600 Received: by cpu.us.dynix.com (AIX 3.2/UCB 5.64/4.03) id AA42220; Fri, 5 Aug 1994 09:24:41 -0600 Date: Fri, 5 Aug 1994 09:21:31 -700 (MDT) From: Jim Conforti Subject: Re: Timing Rule of thumb To: DIY_EFI In-Reply-To: <9408050507.AA09438@coulomb.eng.ohio-state.edu> Message-Id: Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI Steve, et. al .. The BOSCH controllers, at least, include a table like that ... They retard spark as coolant temp increases ... Jim Conforti