DIY_EFI Digest Saturday, September 11 1999 Volume 04 : Number 519 In this issue: Re: Vapour Pressure Re: Volvo/Saab Bosch MAF swap for VAF Wired foo Measuring MAF electronic trans controller diy fly by wire See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- Date: Sat, 11 Sep 1999 09:27:41 +0000 From: "Alex C. Peper" Subject: Re: Vapour Pressure Good set of humidity calculations for engines is in code of federal regulation title 40 section 86.344-79. available in public university. also has water-vapour dry volume calculation alex > Date: Fri, 10 Sep 1999 15:24:29 -0700 > From: "John Dammeyer" > Subject: Vapour Pressure > > Hi All, > > Does anyone have the formulae for Vapor Pressure? If I assume RH is 75% and can > measure the Air Temperature inside the intake manifold what is the calculation > for vp? > > Thanks, > > John > ------------------------------ Date: Sat, 11 Sep 1999 09:27:41 +0000 From: "Alex C. Peper" Subject: Re: Volvo/Saab Bosch MAF swap for VAF I made some controllers for Bosch Hot Wire and Bosch Vane with PIC 73 Used built in 8 bit converter and 10 bit PWM output direct connection on hot wire.( used voltage divider and opamp on 10 V. vane meter.) Was used as O2 sensor adaptive feed back control, with 12 point internal correction table. Also had prototype to load EEPROM values and rpm input. You could look into adjustable gain opamps and DAC's Alex > Some of you may recall that I've been investigating the possibility of > swapping a Bosch MAF from a Saab or Volvo (they call it a AMM), for the > stock Bosch VAF meter in my Merkur XR4Ti (Ford Sierra in the rest of the > world). Here's what I've discovered about the two MAF on the bench: > > '87 Volvo 740 2.3 Turbo MAF Bosch p/n 0 280 212 007 (black plastic > case) > > Pin #1 Ground (MAF signal - local) > Pin #2 Ground for filament burn-off and CO idle adjustment (at PCM) > Pin #3 MAF output (~1 - 5v) > Pin #4 Filament burn-off (4v for 1 second after shut-down, controlled by > PCM) > Pin #5 12v Power input > Pin #6 CO Idle adjustment > > '87 Saab 900 2.0 N/A MAF Bosch p/n 0 280 212 005 (aluminum case) > > Pin #1 Filament burn-off (4v fro 1 second after shut-down, controlled by > PCM) > Pin #2 12v Power input > Pin #3 Ground for filament burn-off and CO idle adjustment (at PCM) > Pin #4 Ground (MAF signal - local) > Pin #5 MAF output (~1 - 5 v) > Pin #6 CO idle adjustment > > For bench testing purposes, I was only using three circuits: The MAF > output & ground and the 12v input (conveniently provided by a fresh > battery). Here's what I discovered: > Powered, still air Powered, maximum human breadth > Volvo MAF 1.32 volts 2.70 volts > Saab MAF 1.55 volts 3.95 volts > > Not surprisingly, the two MAFs are calibrated differently, with the N/A > Saab MAF likely to max out (5v) with much less air flow than the Volvo > turbo MAF. > > Now, back to my replacement objective... The stock Merkur VAF has a base > starting output (powered but no air flow) of .5v, which is much less than > either of these devices (relatively speaking). So I'm thinking about > sticking an in-line POT on the output line to provide an adjustable > base-line voltage and match it to the .5v that the PCM is looking for > from the stock VAF. I realize matching the base-line voltage does not > guarantee a match across the full range, but it's a starting point. What > I'd really like to do is find a way to use the built-in CO idle > adjustment screw, since it will otherwise go un-used since this function > is not supported by the Ford PCM. > > If it turns out that adjusting the MAF output in a monolithic fashion can > not closely reproduce the original VAF output, I'll have to look at a > "black box" solution from vendors such as Split Second or Pro-M which > provide the ability to have 2 or 3 adjustments to the MAF depending upon > the flow. I'm not smart enough to figure that one out myself. > > Any comments, corrections, open discusions, etc are welcome. > > Brad Anesi > (bjanesi@xxx.com) ------------------------------ Date: Sat, 11 Sep 1999 10:53:29 -0400 (EDT) From: William T Wilson Subject: Wired foo On Sat, 11 Sep 1999, DIY_EFI Digest wrote: > Naturally, the experts think it's too good to be true -- although they > can't exactly say why. I don't know why they can't. I can; it violates the Second Law of Thermodynamics. Entropy has to increase. That engine decreases entropy by converting heat energy into rotational energy. The engine has to output entropy somewhere. My guess would be that the problem lies with all the accelerating and decelerating that this engine is supposed to do. How are they going to arrange for that? ------------------------------ Date: Sat, 11 Sep 1999 09:35:41 -0700 From: "John Dammeyer" Subject: Measuring MAF Hi, I'll put in my two cents here. Don't know how clever you are with electronics but if you purchase a differential pressure transducer you can build a simple flow meter by measuring the difference in pressure at two points. Create a supply tube that has a restriction and measure the pressure at the restriction and the point before the restriction. (venturi in effect). As long as you know the temperature of the air flow and the size of the tubes you can calculate the airflow. Then, just use a DC powered fan with a variable power supply to push air through this pipe into the MAF sensor. Alternatively, you might be able to rent a hot wire anemometer from an air conditioning firm and if you place that in the air stream of your air supply you can also calibrate the MAF sensor. I'm willing to bet that once you get a few accurate set points you can probably extrapolate the entire curve. BTW. Thanks for the info on the SAAB. I have a 900 Turbo. Regards, John >Date: Fri, 10 Sep 1999 20:13:57 -0400 >From: bjanesi@xxx.com >Subject: Volvo/Saab Bosch MAF swap for VAF [snip] > >If it turns out that adjusting the MAF output in a monolithic fashion can >not closely reproduce the original VAF output, I'll have to look at a >"black box" solution from vendors such as Split Second or Pro-M which >provide the ability to have 2 or 3 adjustments to the MAF depending upon >the flow. I'm not smart enough to figure that one out myself. > >Any comments, corrections, open discusions, etc are welcome. > >Brad Anesi >(bjanesi@xxx.com) > ------------------------------ Date: Sat, 11 Sep 1999 12:36:32 -0500 From: Jason Haines Subject: electronic trans controller I know this was an old post but someone asked about stand alone electronic transmission controllers (in this case for the 4L60E). I am not sure how easy it would be to make this work but the diesel truck transmission controllers controls the 4L80E transmission. We have used this in many conversion applications to control this very heavy duty transmission. The controller is as follows: 16147609 GM diesel truck 1991-1993 6.5L diesel A sample calibration is as follows 16173828BACZ?CK, 1 ton1992-1993AT6.5L D, "F" Also, DFI/Accel had an aftermarket controller available but only a few made it to the public before they stopped production. FelPro then came out with a controller and I am not sure if it is still available. Jason ------------------------------ Date: Sat, 11 Sep 1999 14:59:16 -0400 From: Chris Conlon Subject: diy fly by wire >> Ok, I'll bite. Electric cruise control units? Is there an aftermarket >> (or cheap OE unit) I can get? The stock cruise control on the car is > >The late model Ford Aerostar uses it, I suspect a lot of other fords as >well. Possibly others. Toyota used one a few years ago, not sure of current Thank you to everyone who helped with info about cruise control stuff. Now I have plenty of leads and feel pretty sure I can get something to do the job. One thing in my favor is that I don't have to use the stock TB or actuator cam. So, if the actuator has a longer, slower throw than what I wanted, I can make up for it with a different TB cam and spring. As for safety, the first line is in the feedback loop that keeps the TB lined up with the position commanded by the right foot. If the TB is too far out of sync for too long (200-300 msec-ish), fuel and spark are cut. When the PWM fuel pressure system is put in, the fuel pump will be cut off also. The second line of safety is a switch so the driver can cut off fuel/spark/fuel pump. As you might guess there's a whole lot of development going on all at once in this project, and I'd really rather not have it get away from me. Also by conincidence I was looking at some Eaton info and they have what is basically a small TB, actuated by a vaccum/diaphragm type of thing. Sort of like a very simple version of the cruise control actuator system. $85 for the generic one, TB bore about 1.5" IIRC. Thanks again, Chris C. ------------------------------ End of DIY_EFI Digest V4 #519 ***************************** To subscribe to DIY_EFI-Digest, send the command: subscribe diy_efi-digest in the body of a message to "Majordomo@xxx. A non-digest (direct mail) version of this list is also available; to subscribe to that instead, replace "diy_efi-digest" in the command above with "diy_efi". Which is of course the well-known acronym for "How the fuck does he do it?" Did you get Casey's recent UK travelogue? > interview circuit with most of the city banks and other interesting places, > I accepted a contract to teach Enterprise Java Beans at a consulting company > here in London about 3 weeks after arriving here. and later... > The company is a Sun certified Authorised Java Centre - actually is one of > two Object Reality Centres in the UK so it's primary role is that of systems > integration, making extensive use of CORBA, EJB and as such there are > partnerships with SUN, BEA, Oracle etc... We primarily go against total OK, I must have underestimated the guy -- or maybe I am just feeling bogged down in the mire...but how did he get into the high-flyer realm of ORBs/CORBA and EJB? This is getting to be space aged stuff -- I hope there is some kind of future in it, as the SA market, at times, seems to be increasingly dominated by MCSE shit, Visual Basic and now MS IIS/NT/ASP/MSSQL. Of which I know almost bugger all. (For my own part, I got as far as building a CORBA ORB and not managing to run a test program for it...supposed to be part of my currently very dormant post-grad research here). I just seem to be drowning in shit to do here. I am trying to write a medium-sized Java project that should be of use to humanity and maybe also to the people at UZ (notice how I draw the distinction). I have about 70% of a doodad that is a server which sits on top of an SQL database and you can feed it from Perl scripts that sit reading the tail of ever growing logfiles. These feed item/quantity counts/cost codes into the server who keeps track of accounts and sessions and bills users/groups/supergroups, etc against whatever they are doing. Primarily the focus is to keep accounts of WWW usage, and the students will be given a quota, which when gone, will mean their authentication to the WWW proxy will fail until they come down and pay money to have their quota raised. Can do against sendmail logs and through-firewall traffic as well. Caches the tallies, of which it has a whole tree-structured hierarchy of cost codes. And is built into a Java-based WWW server so that extensions can be written into the server to show you what is going on as it happens. But it is taking me for fucking ever as I seem to get about an hour every 3rd or 4th day to spend on it. Run more and more in circles, and what is really irritating is to see other folk in Networks not apparently having enough to do here, but not quite capable of learning themselves anything about IP, routing or even basic Unix shell stuff. Currently tearing hair out with trying to hack a script for publishing on Apache with PUT a la Netscape composer. Still not really sure I understand group permissions under *nix. But, as they say... Where do you lot stand now that some number of zillions are to be spent on military procurement? Is APIS going for gold? Who is working on it these days? S.