DIY_EFI Digest Tuesday, March 23 1999 Volume 04 : Number 190 In this issue: Re: Injector Math Re: O2 Sensor Tweaking...and MAF Enlarging... Re: Port intake design RE: Rochester Fuel injection system Re: FI fuel line Fwd: Re: Port intake design Re: O2 Sensor current? Re: Rochester Fuel injection system Re: valve overlap EFI Intake Conversion (2 of 2) EFI Intake Conversion (1 of 2) RE:Rochester Fuel injection system RE: injector manifold design RE: injector manifold design Re: Port intake design Driver Information System Re: Port intake design Re: Rochester Fuel injection system Re: Port intake design Re: Port intake design MPH Diacom reading Re: Port intake design Re: MPH Diacom reading Re: O2 Sensor Tweaking...and MAF Enlarging... Re: Port intake design See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- Date: Tue, 23 Mar 1999 13:25:13 -0500 From: "Bruce Plecan" Subject: Re: Injector Math This is a multi-part message in MIME format. - ------=_NextPart_000_0216_01BE7530.954416A0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable -----Original Message----- From: Walter Sherwin To: diy_efi@xxx.edu = Subject: Re: Injector Math =20 Competetion Cams used to do one ofs. Crane will, but be sure to get the wallet out, and they just might = stonewall ya. For a SBC might try Carl Summers, list member. Bruce =20 =20 as to the bumpstick itself, i'd suggest asking about a "negative = overlap"=20 cam. the cam grinder you want to do biz with will know what = this=20 is and how to tailor it to your situation. the minor added = expense of=20 getting a true custom cam will be more than offset by the = results.=20 IIRC, the latest tt porsche awd turbo used a neg overlap cam.=20 =20 =20 Hi. I'd like to know more about these "negative overlap cams". = Seriously! What are they, and how do they differ from the norm? Ditto = on your comments about finding a cam grinder who will tailor YOUR cam to = YOUR application. Walt. - ------=_NextPart_000_0216_01BE7530.954416A0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable

-----Original = Message-----
From:=20 Walter Sherwin <>
T= o:=20 =20 <>
Subject:=20 Re: Injector Math

Competetion Cams used to do one=20 ofs.

Crane will, but be sure to get the = wallet out,=20 and they just might stonewall ya.

For a SBC might try Carl Summers, = list=20 member.

Bruce

as to the bumpstick itself, i'd suggest asking about a = "negative=20 overlap"
cam. the cam grinder you want to do biz = with=20 will know what this
is and how to tailor it to your = situation. =20 the minor added expense of
getting a true custom cam will be = more=20 than offset by the results.
IIRC, the latest tt porsche awd = turbo=20 used a neg overlap cam.=20

=20

Hi. I'd like to know = more about=20 these "negative overlap cams". Seriously! = What are=20 they, and how do they differ from the norm? Ditto on your = comments=20 about finding a cam grinder who will tailor YOUR cam to YOUR=20 application.

Walt.

- ------=_NextPart_000_0216_01BE7530.954416A0-- ------------------------------ Date: Tue, 23 Mar 1999 12:34:13 -0600 (CST) From: Roger Heflin Subject: Re: O2 Sensor Tweaking...and MAF Enlarging... On Tue, 23 Mar 1999, Kurek, Larry wrote: > Guys: > > There is a major debate going on the F-body lists concerning HP gains from > "porting" the stock MAF. I am arguing that the HP gains being shown on the > dyno (7-10hp), are the result of lean out since the MAF is now out of > calibration and NOT due to the increased airflow. I think the stock MAF > flows around 650-700CFM, which on a NA 350 is MORE than adequate. Also, what > I am arguing, and has been proven by a few list members, is that this gain > is short term, since the PCM will 'relearn" the correct fuel trim values > from the O2 feedback, and adjust the mixture accordingly. So, any leanout > effect will be compensated for by additional fuel and you will be back to > zero gain. One list member has argued that any effect of this learning will > not be applied at WOT since the computer is not in learn mode. Doesn't the > PCM just use the last value in the BLM to adjust WOT fuel? Don't you need to > force this BLM cell to 128 (with custom programming) when going WOT to > negate any learning effect? > THe PCM forces the BLM to 128 if it is below 128. Above 128 stays at whatever value it is at (except on my computer - mine always goes to 128 at wot, couple of internal branches accidently got changed and caused this behavior, I wonder how that happened). If you want to confirm yours does this, watch the blms in diacom or a simlar software during wot, if the value was below 128 when it went wot, the value will change to 128, if above 128 it will stay there. > Finally, and this is my major question to this list. Has anyone ever > considered, or actually built, a voltage adder/subtracter for "massaging" of > the O2 signal? From what I can tell, this is the ONLY way to seriously > impact fuel curves (short of reprogramming) over the long term AND at WOT. > I'm sure you could build something that takes an input voltage and adds or > subtracts, say 0-100mv, and send this signal to the PCM. A nice dial setup > (adjustable pot) could vary the range (I would assume a +/- 100mv range > would work), and have the ability to synchronize two inputs (for a > left/right O2 setup) with the one dial. Doable? If so, how? comments? > I would not lean things out any, since the computer always goes to 128 if the BLM is below 128. I think this is to prevent dangerous conditions, so messing with the O2 would not be able to lean things out more than the original 128. If things were being richend up it could lean it back to the stock 128. I did not notice the MAF discussion on the fourth-gen list, but since I don't have a MAF I probably ignored it. > TTYL! > > Larry > Roger 93 Z28 ------------------------------ Date: Tue, 23 Mar 1999 13:43:45 -0500 From: Frederic Breitwieser Subject: Re: Port intake design > I'd like to follow along, but this really ain't the list for that. > Any one wanna host a mechanical related list?. Um, I could host it if we feel there is a need. - -- Frederic Breitwieser Bridgeport CT 06606 1993 Supercharged Lincoln Continental 1989 HWMMV w/turbocharged 500cid Caddy 1975 Dodge D200 Club Cab soon to have 431 stroker + turbos 2000 (I hope) Buick GTP (Mid-Engined Sports Car) ------------------------------ Date: Tue, 23 Mar 1999 12:41:24 -0600 From: Don.F.Broadus@xxx.com Subject: RE: Rochester Fuel injection system Popular Hot Rodding had a 3 part series on tuning troubleshooting the Rochester mechanical FI. I can fax you the info , but beware it is not for the faint of heart. The article requires 2 special manometers and other equipment to do it right. Pontiac also had Rochester FI up till 1958 I believe. Don > -----Original Message----- > From: Jemison Richard [SMTP:JemisonR@xxx.com] > Sent: Tuesday, March 23, 1999 9:07 AM > To: 'diy_efi@xxx.edu' > Subject: RE:Rochester Fuel injection system > > Does anyone have any trouble shooting information, web sites, etc for a > Rochester Fuel Injection System? Also, does anyone remember the RFI ever > being offered on the big block? This is in a '68 Vette and the symptoms > are > crappy idle and blubbering - any change in settings causes stalling during > gear changes. > > Anything will help. Thanks > > Rick > jemisonr@xxx.com ------------------------------ Date: Tue, 23 Mar 1999 10:44:26 -0800 (PST) From: andy quaas Subject: Re: FI fuel line What kinda TBI was that? The 4bbl ones have NPT fittings. andy - ---Vinnie Moscaritolo wrote: > > > > At 5:00 AM -0500 3/23/99, Vance Rose wrote: > > Have done the same also - works very nice. Saw a post where someone silver > > soldered joints in tubing to make custom lines. Only way i've found to get > > saginaw ends for my pu. > > > > > I wanted to use AN fittings in conjunction with my Holley TBI unit. > Since Holley used a non-standard thread (or at least one I couldn't > find. maybe they are Saginaw..) on the TBI and I couldnt find an > adapter to AN, I cut the Holley connector and silver soldered > (welded) it to a steel AN fitting. I also did the same thing to the > Holley supplied (Carter?) fuel pump.. > > Not to change the subject much but speaking of Holley EFI's I have > heard that some folks run a primary pump (Holley Red pump) near the > tank and then the high pressure pump closer to the TBI. I am curious > if this is necessary and how many people actually do this? > > > Vinnie Moscaritolo > http://www.vmeng.com/vinnie/ > PGP: 3F903472C3AF622D5D918D9BD8B100090B3EF042 > ------------------------------------------------------- > > Those who hammer their swords into plows, > will plow for those who don't." > _________________________________________________________ DO YOU YAHOO!? Get your free @xxx.com ------------------------------ Date: Tue, 23 Mar 1999 10:47:00 -0800 (PST) From: andy quaas Subject: Fwd: Re: Port intake design Here is the last message from James. I will post to the list on this subject. Andy - ---James Weiler wrote: > > > > On Tue, 23 Mar 1999, andy quaas wrote: > > > Sounds like something i can probably do. Did you weld the injector > > bosses in? I could weld up a steel jig to hold the intake. I never > > thought of that. How did you angle your injectors? I found a pic > > yesterday that shows them going straight down. Bar stock for fuel > > rail would work well except i have no way to drill a hole in the > > center of it! I am going to have trouble spacing the intake holes and > > the rail holes the same. That seems to be my only big problem. > > I made the jig out of 1/2 inch plywood. Cheap and easy to work with. It > is essentially a large flat table with a ledge on one side. I push the > intake up against that ledge and clamp it down. Then clamp the jig to > the drill press table. When I'm finished making the hole in the intake I > unclamp the intake slide it over to the next port and clamp it again. > Since the jig never moved it serves as an alignment tool and ensures that > all the holes are in a straight line. I did some carefull measurments > such that the holes I drilled were all equally spaced. This would allow > the fuel rail to go on in either orientation. > > Spacing the rail holes the same is easy. Start with making the intake > first. Once the bosses are welded in (I had someone do that for me) and > you've reamed the inside of the boss (to correct for any shift that occured > from the boss not being held in the right position during welding) you > will now have a 'template' for where the holes must be for the rail. > Measure the distance between and drill away. > > You can get extra long drill bits to drill out the center of some bar > stock for the rail. > > I'll look up those drill bit sizes today. > > HTH > jw > > > _________________________________________________________ DO YOU YAHOO!? Get your free @xxx.com ------------------------------ Date: Tue, 23 Mar 1999 13:56:07 -0500 From: "Gary Derian" Subject: Re: O2 Sensor current? I know of no 3-way cat system where the air is injected at the headers once the engine is warm. As you noted, it would greatly influence the O2 sensor to the point that having a sensor becomes moot. The AIR system on the '77 motor is for open loop and had no O2 sensor. Gary Derian > On Tue, 23 Mar 1999, Gary Derian wrote: > > > Wouldn't you want to operate leaner than stociometric for better economy? > > The AIR should divert to the cat when warm and not affect the O2. Part > > throttle ping can be caused by insufficient EGR. > > > > I don't think a simple resistor in series will work as you want. > > > > Gary Derian > > > > > The air (at least on my vehicle) is injected in at the headers, so the > air should affect the O2 readings, at least I cannot see how it would > not affect the O2 readings. > > I would not think a simple resistor would work either, at least not > that low of resistor, and if they are using a resistor, they are > probably getting both open circuit voltage, and voltage through the > resistor/current through the resistor. I don't think with just one > you can properly figure out battery charactistics. > ------------------------------ Date: Tue, 23 Mar 1999 14:22:29 EST From: ECMnut@xxx.com Subject: Re: Rochester Fuel injection system Hi Gary I think Pontiac offered it on some poncho V8s in the late 50's. Quite rare though... Looks similar to the bow tie setup. A friend of mine tranplanted it into an early GTO. Next time I'm over there, I'll get some digitals of it if anyone cares.. Mike V > The Rochester unit was only offered on small blocks. Check those diaphragms > and linkages for smooth action. There are some bleed passages in the air > meter which adjust the idle fuel. Check those for dirt, etc. ------------------------------ Date: Tue, 23 Mar 1999 14:33:56 EST From: ECMnut@xxx.com Subject: Re: valve overlap > I'm curious (not being picky). Going by the apparent meaning of the phrase > 'lobe separation', wouldn't greater lobe separation mean less overlap? Yep, years ago, Bruce Crower (cams) took it to extremes with turbocharged sand buggies. He went with 114-116 degree C/L, which allowed for longer valve timing, and still no overlap.. Interesting note though, I believe he used 8-10 deg more duration on the INTAKE side than the ex. Crower Cams have been around a long time. If you are putting something together, call them. Cam grinders can offer a wealth of info, as long as you don't get the dufus that just started working there last week... HTH .. Mike V. ------------------------------ Date: Tue, 23 Mar 1999 14:36:55 -0500 From: Frederic Breitwieser Subject: EFI Intake Conversion (2 of 2) > Could we keep this on-list??? I'm starting on the same thing too. Just > picked up some of that aluminum 'brazing' rod last night ($19.95 per > pound at the local welding supply). The second thing I will discuss is how to make an intake from scratch. This was done for a Buick V6, however the same methodology applies to just about any motor. Entirely made of aluminum, brazed together using the alumaloy propane-heated welding rod (durafix is pretty much the same thing). To visualize what I was trying to achieve, I wanted more flow, straight runners, a huge plenum, and a plenum-installed water based intercooler in one package. Autozone didn't have any in stock . I took the "Buick Power Source" which has all the dimensions of the heads, blocks, and intakes, including OEM & Stage I, and Stage II components. I took the dimensions off the head diagram for the intake side, simply transposed it to a 3/8" thick aluminum plate. Drilled the bolt holes, and milled out the intake ports. Then, I whipped out a circular miter saw, replaced the wood blade with a grinding disc, then cut 1"x2" rectangular tubing (outside measurements) at an 20 degree cut on the miter saw for the head plate end. Then, on the other end, 15 inches away, I cut a 55 degree cut (I think) to match the 45 degree plenum shape I was to have. After making six identically shaped intake runners, I then made a plenum. The top of the plenum was a rectangle, and the front or back view was a triangle if that helps you picture this. This was the bottom half of the plenum. I marked everything off with a marker, drilled and milled the openings for the runners, then pushed it all together. Once things were set, I allumalloy'd everything together for the bottom half of the intake (80% at least). Now comes the intercooler portion. I found an aluminum oil/transmission cooler ahead of time, measured it so that my plenum would be a tad larger, then installed the cooling unit on side pieces I made and welded that to the bottom of the plenum. Picture a rectangular box 2" high without a top or a bottom that's the same size as the top of bottom half of the plenum. Once that was together, now comes time to make the top half of the plenum. I made an aluminum box using .120 thickness material as I had for the runners and the bottom of the plenum, drilled out holes for the two throttle body units, drilled mounting holes and alumalloy'd in aluminum nuts that I had a hard time finding, then welded this piece to the intercooler piece, so its all once large piece now. The cooler fittings came out through the side by the way, and I added a ring of welding rod (alumaloy) around both fittings as to keep an air tight seal, as I did with the cooler and the 2" high box it was in anyway. The injector bungs went in at a 30 degree angle to the intake runner sides, and how that's done is by following the previous message I sent (1 of 2) - same process). The equipment I had to make this with was a smitty milling machine at a friend's place, so getting angles correct was fairly easy compared to at home with just a drill press. Anyway, the last piece was the intake manifold bottom, or valley cover. The buick engine needs a hard cover, and its sorta trapazoidal shaped. Measured, cut paper template, and made such a piece, then grinded the edges to fit, then welded in. I must admit that the use of paper templates and scotch tape is a good idea. I made two manifolds before checking the fit closely enough, which obviously is a waste of time, material, and money. I hate to admit to stupidity, however check each and every step twice to be sure you have it right, if you haven't made a much of intakes before. Its a lot more challenging than I'm describing. In fact, the third manifold I made for the Buick V6 was entirely out of cardboard from the back of legal pads taped together, using corragated box cardboard for the head plates and the bottom plates. The only thing I screwed up on the final version of the intake was a hot water crossover from head to head. I somehow, (duh) left that out but I caught it before I actually used it, and ended up with two brass fittings with a larger diameter than the not-so-round holes for the coolant crossover, and a piece of tubing with two circular hose clamps. The beauty of alumaloy (or durafix, whatever) is as long as the metal is non ferrus, you can make dissimilar metals stick to each other very well. Brass, copper, gold, aluminum, etc. Hope that helps you out. If you are converting a carb intake to EFI, the article in the mopar mag has a three-article thing on it, and is written well enough that you can follow along. The pretty pictures help :) - -- Frederic Breitwieser Bridgeport CT 06606 1993 Supercharged Lincoln Continental 1989 HWMMV w/turbocharged 500cid Caddy 1975 Dodge D200 Club Cab soon to have 431 stroker + turbos 2000 (I hope) Buick GTP (Mid-Engined Sports Car) ------------------------------ Date: Tue, 23 Mar 1999 14:43:22 -0500 From: Frederic Breitwieser Subject: EFI Intake Conversion (1 of 2) Eric Aos wrote: > Could we keep this on-list??? I'm starting on the same thing too. Just > picked up some of that aluminum 'brazing' rod last night ($19.95 per > pound at the local welding supply). Well, I can give a quick dissertation of what I did if it helps you. I need to do so anyway and take some pictures of the results for my website anyway. Recent Mopar Conversion: I started off with a Edelbrock aluminum Streetmaster 383, which coincidentally came on my 383 Mopar engine, which I am in the process of stroking to 431 cubes using a 440 crank and probably the 440YJ rods if the chevy rods don't look right. Anyway, the manifold was sand blasted at a local place for $10, brought home, and marked for porting. I marked the 383 heads as well as the intake using the gaskets and a black marker, then carefully ground the openings on the intake so there were no black lines left, fairly deep into the runners as to promote smooth flow throughout the runner. I also got a little carried away with porting the "deck" or the underside of the runners stemming from the plenum area, but not too bad I hope. Then, I measured the different stepped diameters of the injector base, then milled out an aluminum bung that is 2" long to match this. I made it longer so I could clamp it at the top (I used a drill press, not a milling machine) and it could distort with no real issue, it doesn't need to be 2" long. After the different steps were created, I measured the outside diameter of the aluminum tubing that has been milled, then milled a same size hole into each runner perpendicular to the bottom of the manifold. The runners just start to curve at this point towards the head. Injecting at an angle towards the valve probably would have been a better choice, however with my drill press, I couldn't get the manifold to "stay still" even with clamps. So, 90 degrees had to do. Nothing wrong with this, just not necessarily optimum. The holes in the intake were milled, the injector bosses pushed in, then TIG'd to the manifold. I could have used alumaloy or duraweld like I generally preach, but I wanted to practice my TIG welding and had access to a TIG machine. 7 of the 8 holes in the intake were tight, which is good, and one was a little loose, so I "propped" the injector bung up with a piece of wood and made a quick tack with the TIG, then welded the rest of the way around. Now its grinder time again. Anyway, I ground the injector bung so its flush with the bottom of the slightly curved intake runner by hand, doing so for each bung, then using a mill bit in the drill press I ground the top of the injector bungs to the right height, ensuring a good fit with the injector on the first one. Once I got that just right, I locked the drill press so it couldn't drill any further, then repeated the other 7 bungs in this mannor. Push all eight injectors in, and they fit nice and tight. Now, its time to make fuel rails. I managed to find "scrap" 3/4"x3/4" aluminum bar stock, which I bored four holes in each, using the top of the injectors as a guide. I made two of these, one for each side, then attempted to bore a straight hole from one end to the other. The milling bit I had certainly wasn't long enough, so I ended up sending the intake and the injectors out to a machine shop to have them make the fuel rails. Bar stock was free so it wasn't a big deal anyway. The bar stock will end up having each end of the length of stock threaded, for an AN fitting. One will go to the fuel pump, one will go to the regulator. I plan to hose up the fuel rails in parallel, rather than series, putting the regulator towards the front of the motor, and the inlet on the back. All using nice AN fittings once I order them. And that my friend is pretty much it. I used the "Squirt Gun" article in one of the Mopar magazines as a guide, and by coincidence, my system ended up looking very much like their's, minus the fuel rail stock being different. It was a little time consuming, but was also a lot of fun as well. Part 2 of 2 describes the "from scratch" method of making an intake manifold (at least for a Buick V6 ) - -- Frederic Breitwieser Bridgeport CT 06606 1993 Supercharged Lincoln Continental 1989 HWMMV w/turbocharged 500cid Caddy 1975 Dodge D200 Club Cab soon to have 431 stroker + turbos 2000 (I hope) Buick GTP (Mid-Engined Sports Car) ------------------------------ Date: Tue, 23 Mar 1999 13:04:50 -0700 From: bearbvd@xxx.net (Greg Hermann) Subject: RE:Rochester Fuel injection system >Does anyone have any trouble shooting information, web sites, etc for a >Rochester Fuel Injection System? Also, does anyone remember the RFI ever >being offered on the big block? This is in a '68 Vette and the symptoms are >crappy idle and blubbering - any change in settings causes stalling during >gear changes. > >Anything will help. Thanks > >Rick >jemisonr@xxx.com If you call a Pontiac a big block, yes, never on a BBC, either 348/409 or 396/427. Greg ------------------------------ Date: Tue, 23 Mar 1999 12:06:57 -0800 From: "Stowe, Ted-SEA" Subject: RE: injector manifold design yes there is the crossflow head, without valves it sells for about $1200.00, that's without it begin polished or anything. you need a special intake manifold for that too, which is around 400. - -----Original Message----- From: Mike Morrin [mailto:mikem@xxx.nz] Sent: Tuesday, March 23, 1999 1:08 AM To: diy_efi@xxx.edu Subject: RE: injector manifold design At 01:06 pm 22/03/99 -0800, Stowe, Ted-SEA wrote: >I see, thanks. > >that is a nasty problem, and yes it would be a lot of work to resolve. >but I am wondering what is so different from the carb setup on it now. the >same problem must be there I think. ? You could fit an 8 port head. I recently saw an MGB engine with an 8 port, aluminium, cross-flow, after-market head. I suppose you had not budgetted for that.... regards, Mike ------------------------------ Date: Tue, 23 Mar 1999 12:06:57 -0800 From: "Stowe, Ted-SEA" Subject: RE: injector manifold design yes there is the crossflow head, without valves it sells for about $1200.00, that's without it begin polished or anything. you need a special intake manifold for that too, which is around 400. - -----Original Message----- From: Mike Morrin [mailto:mikem@xxx.nz] Sent: Tuesday, March 23, 1999 1:08 AM To: diy_efi@xxx.edu Subject: RE: injector manifold design At 01:06 pm 22/03/99 -0800, Stowe, Ted-SEA wrote: >I see, thanks. > >that is a nasty problem, and yes it would be a lot of work to resolve. >but I am wondering what is so different from the carb setup on it now. the >same problem must be there I think. ? You could fit an 8 port head. I recently saw an MGB engine with an 8 port, aluminium, cross-flow, after-market head. I suppose you had not budgetted for that.... regards, Mike ------------------------------ Date: Tue, 23 Mar 1999 15:12:58 -0500 From: "Bruce Plecan" Subject: Re: Port intake design - -----Original Message----- From: Frederic Breitwieser To: diy_efi@xxx.edu> Date: Tuesday, March 23, 1999 1:51 PM Subject: Re: Port intake design I''m not saying good or bad, it's just we've lost a really good "contributor" over the panhard thread, and I really hate seeing that happen. I don't know what else to do, is why I mention it. Then if some/lots of follks want to go around the bend on tangents, no harm no foul. Bruce >> I'd like to follow along, but this really ain't the list for that. >> Any one wanna host a mechanical related list?. > > >Um, I could host it if we feel there is a need. > ------------------------------ Date: Tue, 23 Mar 1999 09:27:50 -0800 From: jq Subject: Driver Information System has any1 been able to hook up the system that exists in the oldmobile 98 to a 90 firbird/iroc? ------------------------------ Date: Tue, 23 Mar 1999 12:19:59 -0800 (PST) From: andy quaas Subject: Re: Port intake design How is this the wrong list for that? Its as DIY_EFI as it gets. Andy > > I'd like to follow along, but this really ain't the list for that. > > Any one wanna host a mechanical related list?. _________________________________________________________ DO YOU YAHOO!? Get your free @xxx.com ------------------------------ Date: Tue, 23 Mar 1999 15:12:33 -0500 From: "Gary Derian" Subject: Re: Rochester Fuel injection system Yes, of course. I was thinking Chevy only, Doh! Gary Derian > Hi Gary > I think Pontiac offered it on some poncho V8s in the late 50's. > Quite rare though... Looks similar to the bow tie setup. > A friend of mine tranplanted it into an early GTO. > Next time I'm over there, I'll get some digitals of it > if anyone cares.. > Mike V > > > The Rochester unit was only offered on small blocks. Check those diaphragms > > and linkages for smooth action. There are some bleed passages in the air > > meter which adjust the idle fuel. Check those for dirt, etc. ------------------------------ Date: Tue, 23 Mar 1999 12:54:00 -0800 (PST) From: andy quaas Subject: Re: Port intake design We lost a contributor? We can't have that! Maybe the name of this list should be renamed "DIY_EFI_ELECTRONICS". Andy - ---Bruce Plecan wrote: > > > -----Original Message----- > From: Frederic Breitwieser > To: diy_efi@xxx.edu> > Date: Tuesday, March 23, 1999 1:51 PM > Subject: Re: Port intake design > > > I''m not saying good or bad, it's just we've lost a really good > "contributor" over the > panhard thread, and I really hate seeing that happen. > I don't know what else to do, is why I mention it. > Then if some/lots of follks want to go around the bend on tangents, no > harm no foul. > Bruce > > >> I'd like to follow along, but this really ain't the list for that. > >> Any one wanna host a mechanical related list?. > > > > > >Um, I could host it if we feel there is a need. > > > > > > _________________________________________________________ DO YOU YAHOO!? Get your free @xxx.com ------------------------------ Date: Tue, 23 Mar 1999 16:22:29 -0500 From: "Bruce Plecan" Subject: Re: Port intake design - -----Original Message----- From: andy quaas To: diy_efi@xxx.edu> Date: Tuesday, March 23, 1999 3:28 PM Subject: Re: Port intake design >How is this the wrong list for that? Its as DIY_EFI as it gets. Let me rephrase that. As I see the charter it's about the electrical end of EFI, and those relationships. It's not my list, so the discision ain't mine, and I'm not trying to make it Setting up a drill press, while interesting, wouldn't belong in there. Like I said and other tangents, Panhard bars, engine id, engine history, is a strech for being efi related. I just really hate seeing some of the unscribes that I have seen leave all sharing the similiar complaints. The two biggest, archive reading, and non related threads. It just seems that the list isn't really growing, and I worry long term of too many folks leaving. Sorry for the band width Bruce > >Andy > >> > I'd like to follow along, but this really ain't the list for that. >> > Any one wanna host a mechanical related list?. > > >_________________________________________________________ >DO YOU YAHOO!? >Get your free @xxx.com > ------------------------------ Date: Tue, 23 Mar 1999 15:32:56 -0600 From: Carmine Nicoletta Subject: MPH Diacom reading Does anyone know why the MPH reading from C3 ECM is always 0 MPH? Carmine ------------------------------ Date: Tue, 23 Mar 1999 16:36:46 -0500 From: "Bruce Plecan" Subject: Re: Port intake design - -----Original Message----- From: andy quaas To: diy_efi@xxx.edu> Date: Tuesday, March 23, 1999 4:19 PM Subject: Re: Port intake design Lose enough contributors, and won't have to worry about the name. Bruce >We lost a contributor? We can't have that! Maybe the name of this >list should be renamed "DIY_EFI_ELECTRONICS". > >Andy > > >---Bruce Plecan wrote: >> >> >> -----Original Message----- >> From: Frederic Breitwieser >> To: diy_efi@xxx.edu> >> Date: Tuesday, March 23, 1999 1:51 PM >> Subject: Re: Port intake design >> >> >> I''m not saying good or bad, it's just we've lost a really good >> "contributor" over the >> panhard thread, and I really hate seeing that happen. >> I don't know what else to do, is why I mention it. >> Then if some/lots of follks want to go around the bend on >tangents, no >> harm no foul. >> Bruce >> >> >> I'd like to follow along, but this really ain't the list for that. >> >> Any one wanna host a mechanical related list?. >> > >> > >> >Um, I could host it if we feel there is a need. >> > >> >> >> >> > >_________________________________________________________ >DO YOU YAHOO!? >Get your free @xxx.com > ------------------------------ Date: Tue, 23 Mar 1999 16:47:38 -0500 From: "Bruce Plecan" Subject: Re: MPH Diacom reading - -----Original Message----- From: Carmine Nicoletta To: diy_efi@xxx.edu> Date: Tuesday, March 23, 1999 4:42 PM Subject: MPH Diacom reading Works fine, on my 747 stuff (C-3) Bruce >Does anyone know why the MPH reading from C3 ECM is always 0 MPH? > >Carmine > ------------------------------ Date: Wed, 24 Mar 1999 08:50:09 +1000 From: Richard Wakeling Subject: Re: O2 Sensor Tweaking...and MAF Enlarging... Hi Larry, Kurek, Larry wrote: > > Guys: > > There is a major debate going on the F-body lists concerning HP gains from > "porting" the stock MAF. I am arguing that the HP gains being shown on the > dyno (7-10hp), are the result of lean out since the MAF is now out of > calibration and NOT due to the increased airflow. I think the stock MAF > flows around 650-700CFM, which on a NA 350 is MORE than adequate. Also, what > I am arguing, and has been proven by a few list members, is that this gain > is short term, since the PCM will 'relearn" the correct fuel trim values > from the O2 feedback, and adjust the mixture accordingly. So, any leanout > effect will be compensated for by additional fuel and you will be back to > zero gain. One list member has argued that any effect of this learning will > not be applied at WOT since the computer is not in learn mode. Doesn't the > PCM just use the last value in the BLM to adjust WOT fuel? Don't you need to > force this BLM cell to 128 (with custom programming) when going WOT to > negate any learning effect? One of the many maps or tables used by the PCM is called the Air/fuel ratio table. Diacom sees this as the commanded air/fuel ratio. When set to 14.7 A/F (stociometric) BLM comes into play but when set to 12.5 A/F for heavy or full power condition BLM calculations are ignored and BLM will be seen as 128 meaning that we are not in closed loop and we are sitting some where on our A/F table which is not 14.7. During this condition no additional fuel is added by the BLM and this means that we can adjust our full power A/F and no that it will not be leaned off as you thought it might. Cheers Richard. (Love thoes Delco's) > > Finally, and this is my major question to this list. Has anyone ever > considered, or actually built, a voltage adder/subtracter for "massaging" of > the O2 signal? From what I can tell, this is the ONLY way to seriously > impact fuel curves (short of reprogramming) over the long term AND at WOT. > I'm sure you could build something that takes an input voltage and adds or > subtracts, say 0-100mv, and send this signal to the PCM. A nice dial setup > (adjustable pot) could vary the range (I would assume a +/- 100mv range > would work), and have the ability to synchronize two inputs (for a > left/right O2 setup) with the one dial. Doable? If so, how? comments? > > TTYL! > > Larry ------------------------------ Date: Tue, 23 Mar 1999 16:14:08 -0600 From: steve ravet Subject: Re: Port intake design This list is what it is, and I think the vast majority are pleased with it. The Panhard thread was off-topic and it's too bad that we lost a subscriber over it, but that's how it goes. Some people get irritated and forget how to use the delete key. Entire threads can be ruthlessly exterminated with a single press of the delete key, so use it! This list is by far the most focused list I've ever been on. I wouldn't want to change the charter to fit a few who are borderline like/dislike (even if it brought Gar back :-O ). With that said, location of injection ports is certainly a DIY_EFI issue! Let the discussion continue. (It's not something I'm personally interested in, so here comes that delete key again...) :-) - --steve andy quaas wrote: > > We lost a contributor? We can't have that! Maybe the name of this > list should be renamed "DIY_EFI_ELECTRONICS". > > Andy > > ---Bruce Plecan wrote: > > > > > > -----Original Message----- > > From: Frederic Breitwieser > > To: diy_efi@xxx.edu> > > Date: Tuesday, March 23, 1999 1:51 PM > > Subject: Re: Port intake design > > > > > > I''m not saying good or bad, it's just we've lost a really good > > "contributor" over the > > panhard thread, and I really hate seeing that happen. > > I don't know what else to do, is why I mention it. > > Then if some/lots of follks want to go around the bend on > tangents, no > > harm no foul. > > Bruce > > > > >> I'd like to follow along, but this really ain't the list for that. > > >> Any one wanna host a mechanical related list?. > > > > > > > > >Um, I could host it if we feel there is a need. > > > > > > > > > > > > > _________________________________________________________ > DO YOU YAHOO!? > Get your free @xxx.com - -- Steve Ravet steve.ravet@xxx.com Advanced Risc Machines, Inc. www.arm.com ------------------------------ End of DIY_EFI Digest V4 #190 ***************************** To subscribe to DIY_EFI-Digest, send the command: subscribe diy_efi-digest in the body of a message to "Majordomo@xxx. 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