From owner-diy_efi Sat Jun 25 03:05:58 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA06590; Sat, 25 Jun 94 03:05:58 GMT Date: Fri, 17 Jun 94 09:02:33 CDT From: Gregory A. Parmer Message-Id: <9406171402.AA23622@acenet.auburn.edu> To: DIY_EFI Subject: Re: OEM EFI mods? X-Sun-Charset: US-ASCII Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI > Mitchell's manuals give better diagrams of things, as well as the > manufacturer's service manuals. The tech schools usually get a lot > of in-depth info from the man's, but I never could find any ECM > diagrams. I wonder if the ECM rebuilders would be any help. They > probably have a non-disclosure agreement against that, though. ... > > What are you trying to adapt? What I'll be doing should be a simple retrofit of a GM EFI to an old Camaro. What exact system I'll start with will depend on price, availability and the valued opinions of others who've done such conversions. I'd really like to know what was happening inside the "black box" before I install one on my prize and joy. Buying the commercially available SW for modifying parameters seems like a terrible copout. The system will first be installed on a well (over?) cammed 283ci. A 400 will replace the 283 when she blows, or needs major work, or when I get my next bonus....whichever comes first. Adjustability is an obvious factor for my EFI selection. I know of people who've done the conversion, but it surprises me that there aren't writeups available on the net. I'm hoping this line of questions will change that, or at least uncover those things that are available. And then there's that well kept secret about the format and meaning of the data of the EPROM...... -greg From owner-diy_efi Sat Jun 25 03:08:48 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA06606; Sat, 25 Jun 94 03:08:48 GMT Date: Fri, 17 Jun 94 09:02:33 CDT From: Gregory A. Parmer Message-Id: <9406171402.AA23622@acenet.auburn.edu> To: DIY_EFI Subject: Re: OEM EFI mods? X-Sun-Charset: US-ASCII Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI > Mitchell's manuals give better diagrams of things, as well as the > manufacturer's service manuals. The tech schools usually get a lot > of in-depth info from the man's, but I never could find any ECM > diagrams. I wonder if the ECM rebuilders would be any help. They > probably have a non-disclosure agreement against that, though. ... > > What are you trying to adapt? What I'll be doing should be a simple retrofit of a GM EFI to an old Camaro. What exact system I'll start with will depend on price, availability and the valued opinions of others who've done such conversions. I'd really like to know what was happening inside the "black box" before I install one on my prize and joy. Buying the commercially available SW for modifying parameters seems like a terrible copout. The system will first be installed on a well (over?) cammed 283ci. A 400 will replace the 283 when she blows, or needs major work, or when I get my next bonus....whichever comes first. Adjustability is an obvious factor for my EFI selection. I know of people who've done the conversion, but it surprises me that there aren't writeups available on the net. I'm hoping this line of questions will change that, or at least uncover those things that are available. And then there's that well kept secret about the format and meaning of the data of the EPROM...... -greg From owner-diy_efi Sat Jun 25 03:09:36 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA06618; Sat, 25 Jun 94 03:09:36 GMT Date: Fri, 17 Jun 94 09:02:33 CDT From: Gregory A. Parmer Message-Id: <9406171402.AA23622@acenet.auburn.edu> To: DIY_EFI Subject: Re: OEM EFI mods? X-Sun-Charset: US-ASCII Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI > Mitchell's manuals give better diagrams of things, as well as the > manufacturer's service manuals. The tech schools usually get a lot > of in-depth info from the man's, but I never could find any ECM > diagrams. I wonder if the ECM rebuilders would be any help. They > probably have a non-disclosure agreement against that, though. ... > > What are you trying to adapt? What I'll be doing should be a simple retrofit of a GM EFI to an old Camaro. What exact system I'll start with will depend on price, availability and the valued opinions of others who've done such conversions. I'd really like to know what was happening inside the "black box" before I install one on my prize and joy. Buying the commercially available SW for modifying parameters seems like a terrible copout. The system will first be installed on a well (over?) cammed 283ci. A 400 will replace the 283 when she blows, or needs major work, or when I get my next bonus....whichever comes first. Adjustability is an obvious factor for my EFI selection. I know of people who've done the conversion, but it surprises me that there aren't writeups available on the net. I'm hoping this line of questions will change that, or at least uncover those things that are available. And then there's that well kept secret about the format and meaning of the data of the EPROM...... -greg From owner-diy_efi Sat Jun 25 03:09:57 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA06629; Sat, 25 Jun 94 03:09:57 GMT Date: Sat, 25 Jun 94 03:09:57 GMT From: owner-diy_efi Message-Id: <9406250309.AA06629@coulomb.eng.ohio-state.edu> Apparently-To: -d Apparently-To: diy_efi-outgoing delete me From owner-diy_efi Sat Jun 25 04:16:13 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA07303; Sat, 25 Jun 94 04:16:13 GMT Received: by coulomb.eng.ohio-state.edu (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 AA07298; Sat, 25 Jun 94 00:16:12 -0400 Date: Sat, 25 Jun 94 00:16:12 -0400 From: jsg (John S Gwynne) Message-Id: <9406250416.AA07298@coulomb.eng.ohio-state.edu> Apparently-To: diy_efi Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI Received: by coulomb.eng.ohio-state.edu (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 AA07203; Sat, 25 Jun 94 00:14:52 -0400 Date: Thu, 16 Jun 1994 17:34:18 -0500 From: Ken King Message-Id: <199406162234.RAA20143@uahcs2.cs.uah.edu> To: DIY_EFI Subject: Re: diy_efi WWW page greetings: you offered, and i'll take you up on it. www. i know what it stands for, and some of the basics, but could use a faq-like starter (or the man page (or pointer thereto) for an ascii version (i dial in to the local university for my unix access). help? later, :) kc From owner-diy_efi Sat Jun 25 04:20:42 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA07411; Sat, 25 Jun 94 04:20:42 GMT Received: by coulomb.eng.ohio-state.edu (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 AA07203; Sat, 25 Jun 94 00:14:52 -0400 Date: Thu, 16 Jun 1994 17:34:18 -0500 From: Ken King Message-Id: <199406162234.RAA20143@uahcs2.cs.uah.edu> To: DIY_EFI Subject: Re: diy_efi WWW page Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI greetings: you offered, and i'll take you up on it. www. i know what it stands for, and some of the basics, but could use a faq-like starter (or the man page (or pointer thereto) for an ascii version (i dial in to the local university for my unix access). help? later, :) kc From owner-diy_efi Sat Jun 25 04:23:12 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA07471; Sat, 25 Jun 94 04:23:12 GMT Received: by coulomb.eng.ohio-state.edu (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 AA07203; Sat, 25 Jun 94 00:14:52 -0400 Date: Thu, 16 Jun 1994 17:34:18 -0500 From: Ken King Message-Id: <199406162234.RAA20143@uahcs2.cs.uah.edu> To: DIY_EFI Subject: Re: diy_efi WWW page Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI greetings: you offered, and i'll take you up on it. www. i know what it stands for, and some of the basics, but could use a faq-like starter (or the man page (or pointer thereto) for an ascii version (i dial in to the local university for my unix access). help? later, :) kc From owner-diy_efi Sat Jun 25 04:24:03 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA07617; Sat, 25 Jun 94 04:24:03 GMT Received: by coulomb.eng.ohio-state.edu (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 AA07612; Sat, 25 Jun 94 00:24:02 -0400 Date: Sat, 25 Jun 94 00:24:02 -0400 From: jsg (John S Gwynne) Message-Id: <9406250424.AA07612@coulomb.eng.ohio-state.edu> Apparently-To: diy_efi Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI Received: by coulomb.eng.ohio-state.edu (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 AA07203; Sat, 25 Jun 94 00:14:52 -0400 Date: Thu, 16 Jun 1994 17:34:18 -0500 From: Ken King Message-Id: <199406162234.RAA20143@uahcs2.cs.uah.edu> To: DIY_EFI Subject: Re: diy_efi WWW page greetings: you offered, and i'll take you up on it. www. i know what it stands for, and some of the basics, but could use a faq-like starter (or the man page (or pointer thereto) for an ascii version (i dial in to the local university for my unix access). help? later, :) kc From owner-diy_efi Sat Jun 25 04:24:39 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA07729; Sat, 25 Jun 94 04:24:39 GMT Received: by coulomb.eng.ohio-state.edu (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 AA07724; Sat, 25 Jun 94 00:24:36 -0400 Date: Sat, 25 Jun 94 00:24:36 -0400 From: jsg (John S Gwynne) Message-Id: <9406250424.AA07724@coulomb.eng.ohio-state.edu> Apparently-To: diy_efi Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI hi From owner-diy_efi Sat Jun 25 04:26:28 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA07909; Sat, 25 Jun 94 04:26:28 GMT Received: by coulomb.eng.ohio-state.edu (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 AA07904; Sat, 25 Jun 94 00:26:27 -0400 Date: Sat, 25 Jun 94 00:26:27 -0400 From: jsg (John S Gwynne) Message-Id: <9406250426.AA07904@coulomb.eng.ohio-state.edu> Apparently-To: diy_efi Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI Received: by coulomb.eng.ohio-state.edu (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 AA07203; Sat, 25 Jun 94 00:14:52 -0400 Date: Thu, 16 Jun 1994 17:34:18 -0500 From: Ken King Message-Id: <199406162234.RAA20143@uahcs2.cs.uah.edu> To: DIY_EFI Subject: Re: diy_efi WWW page greetings: you offered, and i'll take you up on it. www. i know what it stands for, and some of the basics, but could use a faq-like starter (or the man page (or pointer thereto) for an ascii version (i dial in to the local university for my unix access). help? later, :) kc From owner-diy_efi Sat Jun 25 04:27:17 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA07966; Sat, 25 Jun 94 04:27:17 GMT Received: by coulomb.eng.ohio-state.edu (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 AA07203; Sat, 25 Jun 94 00:14:52 -0400 Date: Thu, 16 Jun 1994 17:34:18 -0500 From: Ken King Message-Id: <199406162234.RAA20143@uahcs2.cs.uah.edu> To: DIY_EFI Subject: Re: diy_efi WWW page Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI greetings: you offered, and i'll take you up on it. www. i know what it stands for, and some of the basics, but could use a faq-like starter (or the man page (or pointer thereto) for an ascii version (i dial in to the local university for my unix access). help? later, :) kc From owner-diy_efi Sat Jun 25 04:29:32 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA08056; Sat, 25 Jun 94 04:29:32 GMT Received: by coulomb.eng.ohio-state.edu (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 AA07203; Sat, 25 Jun 94 00:14:52 -0400 Date: Thu, 16 Jun 1994 17:34:18 -0500 From: Ken King Message-Id: <199406162234.RAA20143@uahcs2.cs.uah.edu> To: DIY_EFI Subject: Re: diy_efi WWW page Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI greetings: you offered, and i'll take you up on it. www. i know what it stands for, and some of the basics, but could use a faq-like starter (or the man page (or pointer thereto) for an ascii version (i dial in to the local university for my unix access). help? later, :) kc From owner-diy_efi Sat Jun 25 04:33:31 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA08270; Sat, 25 Jun 94 04:33:31 GMT Received: by coulomb.eng.ohio-state.edu (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 AA08265; Sat, 25 Jun 94 00:33:30 -0400 Message-Id: <9406250433.AA08265@coulomb.eng.ohio-state.edu> From: Dale Ulan Subject: Re: OEM EFI mods? To: DIY_EFI Date: Tue, 21 Jun 94 17:29:12 MDT In-Reply-To: <9406151534.AA08910@ohura.cca.rockwell.com>; from "sdbartho@cca.rockwell.com" at Jun 15, 94 10:34 am Mailer: Elm [revision: 70.85] Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI > Mitchell's manuals give better diagrams of things, as well as the > manufacturer's service manuals. The tech schools usually get a lot > of in-depth info from the man's, but I never could find any ECM > diagrams. I wonder if the ECM rebuilders would be any help. They > probably have a non-disclosure agreement against that, though. And modifying the hardware doesn't help much anyways. All of the work is done inside the CPU... the key here is software. You're *not* going to get any information on that stuff, not from anybody. I *could* tell you how to get a start on modifying the stuff, but I've already been in enough trouble with this stuff already.... -Dale From owner-diy_efi Sat Jun 25 04:33:44 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA08321; Sat, 25 Jun 94 04:33:44 GMT Received: by coulomb.eng.ohio-state.edu (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 AA08316; Sat, 25 Jun 94 00:33:43 -0400 Date: Thu, 16 Jun 1994 17:34:18 -0500 From: Ken King Message-Id: <199406162234.RAA20143@uahcs2.cs.uah.edu> To: DIY_EFI Subject: Re: diy_efi WWW page Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI greetings: you offered, and i'll take you up on it. www. i know what it stands for, and some of the basics, but could use a faq-like starter (or the man page (or pointer thereto) for an ascii version (i dial in to the local university for my unix access). help? later, :) kc From owner-diy_efi Sat Jun 25 04:33:55 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA08334; Sat, 25 Jun 94 04:33:55 GMT Received: by coulomb.eng.ohio-state.edu (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 AA08329; Sat, 25 Jun 94 00:33:54 -0400 Date: Fri, 17 Jun 94 09:02:33 CDT From: Gregory A. Parmer Message-Id: <9406171402.AA23622@acenet.auburn.edu> To: DIY_EFI Subject: Re: OEM EFI mods? X-Sun-Charset: US-ASCII Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI > Mitchell's manuals give better diagrams of things, as well as the > manufacturer's service manuals. The tech schools usually get a lot > of in-depth info from the man's, but I never could find any ECM > diagrams. I wonder if the ECM rebuilders would be any help. They > probably have a non-disclosure agreement against that, though. ... > > What are you trying to adapt? What I'll be doing should be a simple retrofit of a GM EFI to an old Camaro. What exact system I'll start with will depend on price, availability and the valued opinions of others who've done such conversions. I'd really like to know what was happening inside the "black box" before I install one on my prize and joy. Buying the commercially available SW for modifying parameters seems like a terrible copout. The system will first be installed on a well (over?) cammed 283ci. A 400 will replace the 283 when she blows, or needs major work, or when I get my next bonus....whichever comes first. Adjustability is an obvious factor for my EFI selection. I know of people who've done the conversion, but it surprises me that there aren't writeups available on the net. I'm hoping this line of questions will change that, or at least uncover those things that are available. And then there's that well kept secret about the format and meaning of the data of the EPROM...... -greg From owner-diy_efi Sat Jun 25 04:34:02 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA08347; Sat, 25 Jun 94 04:34:02 GMT Received: by coulomb.eng.ohio-state.edu (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 AA08342; Sat, 25 Jun 94 00:34:00 -0400 Date: Sat, 25 Jun 94 00:34:00 -0400 From: jsg (John S Gwynne) Message-Id: <9406250434.AA08342@coulomb.eng.ohio-state.edu> Apparently-To: diy_efi Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI From owner-diy_efi Sat Jun 25 04:34:43 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA08422; Sat, 25 Jun 94 04:34:43 GMT Received: by coulomb.eng.ohio-state.edu (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 AA08355; Sat, 25 Jun 94 00:34:09 -0400 Date: Sat, 25 Jun 94 00:34:09 -0400 From: jsg (John S Gwynne) Message-Id: <9406250434.AA08355@coulomb.eng.ohio-state.edu> Apparently-To: diy_efi Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI help From owner-diy_efi Wed Jun 29 14:19:57 1994 Received: by coulomb.eng.ohio-state.edu (920330.SGI/920502.SGI) id AA26516; Wed, 29 Jun 94 14:19:57 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 AA26511; Wed, 29 Jun 94 10:19:55 -0400 Message-Id: <9406291419.AA26511@coulomb.eng.ohio-state.edu> Date: 29 Jun 1994 08:23:38 -0700 From: "Ciciora Steve" Subject: 16 x 16 lookup tables To: DIY_EFI, sciciora@aztec.al.bldrdoc.gov Sender: owner-diy_efi Precedence: bulk Reply-To: DIY_EFI What do you people think about look up tables? I seem to remember years back in a DFI catalog that they used 16 x 16 look up tables with 4 point linear interpolation. Without having any hands on experience with EFI systems, this is what I plan to use in my system. For the fuel map, I will have an 8 bit RPM go in on one axis and an 8 bit "Density of Air" number (calculated from Air Intake Temp and MAP pressure) go in on the other axis. The output will be an 8 bit pulse width. I will use the 4 most significant bits of each byte (hence the 16 x 16 table part) to get the 4 nearest points to linearly interpolate between. I will then take the top two points and do a linear fit to them (y=mx+b) and plug in the lower 4 bit number into x. Dito for the bottom two points. Then I will take these two y values, do another linear fit (y=mx+b) and this result will be my pulse width. Hmm, reading the above isn't too clear to me, so let me try to re-word it. Assume these names for the 4 points: A B X1 and X2 are the 4 bit lower nibbles to interpolate with. C D Y1=(B-A)*X1 + A Y2=(D-C)*X1 + C Result=(Y2-Y1)*X2 + Y2 A, B, C, and D are 8 bit unsigned numbers. X1 and X2 are 4 bit unsigned numbers. (B-A) and (D-C) are 8 bit signed tempoary results. Y1 and Y2 are (8 bits good enough?) signed numbers. Although the 68332 (sp?) looks like an ideal processor to use because of the timer unit, I have too much time, $$, and effort invested in the 6811. I will be implementing the above in assembly language. Does anyone have any comments/suggestions to the above? Am I on the right track? In thinking about how a carb works, I would need a 'Modifier' for the EFI equivilent of a choke on a carb (works off coolent temp?) and a modifier for the accelerator pump (works off the rate at which the gas petal is being pressed down). Besides for a ignition curve, what else would I need a lookup table for? Thanks for your help, -Steven Ciciora sciciora@aztec.al.bldrdoc.gov