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Bob D
 Post subject: EFI update
PostPosted: Wed Dec 19, 2001 7:34 pm 
Well winter is here and I've stopped driving the Barracuda until spring. Since last May I've put 4400 miles on the EFI conversion and it seems like now is a good time for an update. Actually, there isn't much to tell since there haven't been any problems or glitches. I just drove and enjoyed the car. Initially my idle was a little high at about 800 RPM. Early in the summer I disconnected the Idle Air Control motor and was able to run the idle down to 550 RPM. The IAC acts much like the fast idle function on a carburetor and was not needed during the warm weather. During September I switched back to the IAC. Other than that I haven't had to touch the system. By the way, last winter I left the car outside one night when the temperature was going down to -15 degrees F just to see how well it would start. It started instantaneously and drove immediately with absolutely no hesitation, just like a modern car.
Over the 4400 miles I've averaged 16.4 MPG with an automatic transmission and 3.21:1, 8¼ rear end ratio. (The speedometer gear was changed for the 3.21:1 rear end). That's not great, but considering that it includes all of my driving; city, highway (usually at 75 MPH), AC on quite often, and the fact that I don't baby this car, I'm pretty happy with the results.

A couple of months ago I posted a message suggesting that anyone performing this conversion switch to an electronic voltage regulator. It has since occurred to me that I had also converted to the later dual field alternator a number of years ago. I'm not sure that the early single field alternator would support the increased current demands of the EFI system. If anyone ever tries this maybe they'll let us know.

Bob D


BBobbias@aol.com
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Doctor Dodge (Doug Dutra)
PostPosted: Wed Dec 19, 2001 10:28 pm 
Great up-date Bob, thanks for the follow-up post.
It's nice to have a successful and well documented conversion to help lead the way for others.

EFI is the way of the future and the sooner we can get EFI conversions onto our "old iron", the longer we can ejoy them as trouble-free daily drivers.

Thanks again for taking the time to document and share your EFI conversion work with all of us.
DD

Bob's EFI SL6 Article
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GTS225
PostPosted: Thu Dec 20, 2001 7:11 am 
Say, Bob....something comes to mind. Did you get a batch of error codes when first putting the system into use? I can't help but wonder what will happen when the primary ECU doesn't "see" some of the sensors and/or loads that it's expecting to see.
I know you fooled the ECU with the potentiometer in place of the coolant temp sensor, but I'm thinking about some of the others.

Roger

GTS225@aol.com
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Bob D
PostPosted: Thu Dec 20, 2001 6:32 pm 
Quote:
: Say, Bob....something comes to mind. Did you
: get a batch of error codes when first
: putting the system into use? I can't help
: but wonder what will happen when the primary
: ECU doesn't "see" some of the
: sensors and/or loads that it's expecting to
: see.
: I know you fooled the ECU with the
: potentiometer in place of the coolant temp
: sensor, but I'm thinking about some of the
: others.
:
: Roger


Well I just checked the stored codes in my ECM. Because I'm not using a GM ignition module, or the electronic spark control (ESC), codes 42 and 43 are always present as expected. Codes 14 and 44 were also present. Code 14 is set if the signal voltage from the temperature sensor indicated a coolant temperature above 285 degrees at some point. I'm sure this was set because of the manual potentiometer that I use in place of the temperature sensor. Code 44 is a lean exhaust indication and is set if at some time the exhaust was lean for 50 seconds or longer after the engine was running for at least 1 minute. I don't know why that was set. It may also have been caused by the potentiometer (?). These are the only codes that I got. There isn't any code related to the IAC motor and the ECM doesn't seem to be bothered by the lack of vehicle speed, EGR or any of the other possible inputs . At any rate the presence of these codes won't have any detrimental effect on the system (unless of course some critical sensor really isn't working). My experience is that the engine always goes into closed loop after only a few minutes of operation from a cold start (as long as I also have the potentiometer set for the "hot" position). I can tell when it's in closed loop because I always run the ECM in the field service mode (diagnostic terminal A9 grounded with the engine running). The fault code light will blink at a rate of about one blink per second when running closed loop in the field service mode, and faster if running open loop.
Roger, how are you coming on your EFI project? Is a turbo also in your future? I've started investigating a turbo and am anxious to compare notes on a SL6 EFI/turbo combination.

Bob D



BBobbias@aol.com
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GTS225
PostPosted: Fri Dec 21, 2001 6:42 am 
Because I'm not using a GM ignition module, or the electronic spark control (ESC), codes 42 and 43 are always present as expected.
*************************************************
Well, I anticipate using those, so no worries, there.

There isn't any code related to the IAC motor and the ECM doesn't seem to be bothered by the lack of vehicle speed, EGR or any of the other possible inputs .
**************************************************
Good to hear it. I had some slight worries about those, but wasn't sweating it too much. I was more worried about the fault light blinking unexpectedly, say if conditions happened to be right that the ECM wanted to shift the trans into OD, and it didn't get a return confirmation signal back. As I recall, there's a normally open set of contacts shown on the schematic for that purpose.
Quote:
:
: Roger, how are you coming on your EFI project?

Is a turbo also in your future? I've started
investigating a turbo and am anxious to compare notes on a SL6 EFI/turbo combination.
*************************************************
Budget has slowed things down for the time being, Bob, but planning still goes on. I'm thinking about spending a few bucks and getting the MSD alum fittings that they offer, and having them welded into an Offy intake I have. It shouldn't be too hard from there to build a fuel rail and mount the throttle body.
Still plan on using an external hi-press. fuel pump from Ford full-size pickup, and the Moroso fill tube dump kit for return.
Actually, my original plan is to try a Paxton, or other brand radial supercharger. If I'm not mistaken, those don't need oil supply plumbing, so installation should be simpler. I'm still wondering if the ECU & MAF can handle the additional airflow. I'll probably have to get larger injectors, say from the turbo GNX or similar.

I think the first thing I need to do is build a new engine with those mods in mind. I'll probably have to o-ring the block or head for the higher cyl. pressures, as well as a "breather" cyl.head and upgraded oiling system. Figuring on roughly 9-9.5 comp. ratio, with (hopefully) 12-14 psi boost as a final goal. Think I'll break into the 12-second quarter with that combo? :-D

Roger


GTS225@aol.com
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Bob D
 Post subject: Re: EFI / BOOST
PostPosted: Sat Dec 22, 2001 5:28 pm 
Quote:
: Because I'm not using a GM ignition module, or
: the electronic spark control (ESC), codes 42
: and 43 are always present as expected.
:
: *************************************************
: Well, I anticipate using those, so no worries,
: there.
:
: There isn't any code related to the IAC motor
: and the ECM doesn't seem to be bothered by
: the lack of vehicle speed, EGR or any of the
: other possible inputs .
:
: **************************************************
: Good to hear it. I had some slight worries
: about those, but wasn't sweating it too
: much. I was more worried about the fault
: light blinking unexpectedly, say if
: conditions happened to be right that the ECM
: wanted to shift the trans into OD, and it
: didn't get a return confirmation signal
: back. As I recall, there's a normally open
: set of contacts shown on the schematic for
: that purpose.
: Is a turbo also in your future? I've started
: investigating a turbo and am anxious to compare
: notes on a SL6 EFI/turbo combination.
:
: *************************************************
: Budget has slowed things down for the time
: being, Bob, but planning still goes on. I'm
: thinking about spending a few bucks and
: getting the MSD alum fittings that they
: offer, and having them welded into an Offy
: intake I have. It shouldn't be too hard from
: there to build a fuel rail and mount the
: throttle body.
: Still plan on using an external hi-press. fuel
: pump from Ford full-size pickup, and the
: Moroso fill tube dump kit for return.
: Actually, my original plan is to try a Paxton,
: or other brand radial supercharger. If I'm
: not mistaken, those don't need oil supply
: plumbing, so installation should be simpler.
: I'm still wondering if the ECU & MAF can
: handle the additional airflow. I'll probably
: have to get larger injectors, say from the
: turbo GNX or similar.
:
: I think the first thing I need to do is build a
: new engine with those mods in mind. I'll
: probably have to o-ring the block or head
: for the higher cyl. pressures, as well as a
: "breather" cyl.head and upgraded
: oiling system. Figuring on roughly 9-9.5
: comp. ratio, with (hopefully) 12-14 psi
: boost as a final goal. Think I'll break into
: the 12-second quarter with that combo? :-D
:
: Roger


Sounds like you've started a plan. I think that the MAF sensor is the same on both the natural aspiring 3.8L and the 3.8L turbo. So we should be OK there. The 3.8L turbo ECM is different though, and is sequential, so we can't use it. I think that's where we'll have to innovate. Larger injectors and increased fuel pressure will help, but only to a point. It is possible to burn your own ECM chip, but this requires some specialized equipment and expertise.
<A HREF="http://www.diy-efi.org/gmecm/faq/starti ... ng.html</A>.
Another possibility might be to use an extra enrichment injector(s) that is only activated during boost. Maybe even a throttle body injector that would be used along with the multi-port injectors during boost. Lots to think about!

Bob D



BBobbias@aol.com
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David Kysar
 Post subject: Re: EFI / BOOST
PostPosted: Mon Dec 24, 2001 12:22 pm 
Quote:
: Sounds like you've started a plan. I think that
: the MAF sensor is the same on both the
: natural aspiring 3.8L and the 3.8L turbo. So
: we should be OK there. The 3.8L turbo ECM is
: different though, and is sequential, so we
: can't use it. I think that's where we'll
: have to innovate. Larger injectors and
: increased fuel pressure will help, but only
: to a point. It is possible to burn your own
: ECM chip, but this requires some specialized
: equipment and expertise.
: <A HREF="http://www.diy-efi.org/gmecm/faq/starti ... ng.html</A> .
: Another possibility might be to use an extra
: enrichment injector(s) that is only
: activated during boost. Maybe even a
: throttle body injector that would be used
: along with the multi-port injectors during
: boost. Lots to think about!
:
: Bob D


Mr. DiBiase, I have been doing alot of research into turbos and EFI for a while now. I am an ex-automotive engineer (now Harley) with a long appreciation for Turbo Buicks, BMW's, A and E body Mopars. I've been looking for a chassis/engine combo to build a turbo car when I stumbled on your article. Really with a SL6 mopar the best features of my my favorite cars can be rolled into one: the inline 6 torque and balance of the BMW, the power of the Buick GN, and the nostalgia of the Mopar.

Mabey a mailing list could be put together the EFI/Turbo SL6 concepts?

kysard55@suscom.net
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Bob D
 Post subject: Re: EFI / BOOST
PostPosted: Wed Dec 26, 2001 10:55 am 
Quote:
: Mr. DiBiase, I have been doing alot of research
: into turbos and EFI for a while now. I am an
: ex-automotive engineer (now Harley) with a
: long appreciation for Turbo Buicks, BMW's, A
: and E body Mopars. I've been looking for a
: chassis/engine combo to build a turbo car
: when I stumbled on your article. Really with
: a SL6 mopar the best features of my my
: favorite cars can be rolled into one: the
: inline 6 torque and balance of the BMW, the
: power of the Buick GN, and the nostalgia of
: the Mopar.
:
: Mabey a mailing list could be put together the
: EFI/Turbo SL6 concepts?


Actually David, this forum is probably the best place to discuss EFI / turbo ideas for the SL6 and I would encourage you to "jump in". As you can see from some of the posts, there's already a lot of interest in "boosting" the SL6. A couple of other turbo discussion sites that you might want to check out are: <A HREF="http://groups.yahoo.com/group/jyturbo/" ... yturbo/</A> and <A HREF="http://www.gnttype.org/discus/messages/ ... cs.html</A>. The first is aimed at pulling together a turbo set-up from "junk yard" parts. Of course there are also the turbo supplier sites like <A HREF="http://www.turboneticsinc.com">www.turboneticsinc.com</A> and <A HREF="http://www.turbocity.com">www.turbocity.com</A>.
If any one knows of any other good turbo related sites let us know.
Bob D



BBobbias@aol.com
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Bob D
 Post subject: Re: EFI / BOOST
PostPosted: Thu Dec 27, 2001 8:07 pm 
Quote:
: Mr. DiBiase, I have been doing alot of research
: into turbos and EFI for a while now. I am an
: ex-automotive engineer (now Harley) with a
: long appreciation for Turbo Buicks, BMW's, A
: and E body Mopars. I've been looking for a
: chassis/engine combo to build a turbo car
: when I stumbled on your article. Really with
: a SL6 mopar the best features of my my
: favorite cars can be rolled into one: the
: inline 6 torque and balance of the BMW, the
: power of the Buick GN, and the nostalgia of
: the Mopar.
:
: Mabey a mailing list could be put together the
: EFI/Turbo SL6 concepts?


Also check out <A HREF="http://www.majesticturbo.com/index.html ... ex.html</A>. Lots of good info there, and it looks like they would be helpful with a custom turbo build-up. They also sponsor the worlds fastest pro gas Harley drag bike.


BBobbias@aol.com
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