DIY_EFI Digest Wednesday, May 19 1999 Volume 04 : Number 294 In this issue: Re: Limited cooling space Re: Limited cooling space Re: Mr Helmholz - simple model Re: Ignition advance, was Re: alternative engines, WARPED RE: Limited cooling space Re: O2 Volts Re: Limited cooling space Re: O2 Volts Re: Limited cooling space Re: 1227749 Re: 1227749 Re: Mr Helmholz - simple model Re: Mr Helmholz - simple model Re: EGOR, ION, Trionic Re: Limited cooling space Re: 1227749 Re: Ignition advance, was Re: alternative engines, WARPED EGR? Re: O2 Volts Re: EGR? Re: O2 Volts Re: O2 Volts Re: EGR? Re: O2 Volts Re: EGR? Re: O2 Volts Re: Limited cooling space See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- Date: Wed, 19 May 1999 16:41:37 -0400 From: Ken Kelly Subject: Re: Limited cooling space Frederic, I think you are missing a point. If you divide the radiator into thirds then the water has to flow three times as fast in each tube to maintain the flow rate. Therefore the time the water remains in the radiator is the same in both cases. Ken Frederic Breitwieser wrote: > > > The way I see it, the coolant now "sees" a radiator that is 1/3 as high and > > 3 times longer. Why does this cool better than normal. The log delta T is > > the same, no? Is it a flow turbulence thing? That is the only change I > > see. > > Here would be my guess... > > If you increase the width of the radiator, the coolant has to move > further to reach the other side and be sucked back into the system, > therefore its exposed to the ambient (and hopefully cooler) air > temperature, which reduces the temperature of the coolant going back > in. > > While my dilbert-cube-mates think I'm insane, I just tried something > that you can do that will illustrate the point. > > Run the hot water on your faucet for a few minutes, until the > temperature is constant. Stick a thermometer into a coffee mug, then > fill it with hot water. Record temperature. > > Then, using a second thermometer, or cool off the first one to room > temperature, repeat the experiment, however use the hose with the > spray gun, which typically has 5-6 feet of hose under it. The > temperature in the mug is consistantly 5-6 degrees colder. I did this > 3 times to make sure. > > Longer hose, more distance traveled, more energy (heat) lost or > radiated into "space". > > -- > > 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: Wed, 19 May 1999 16:43:02 -0400 From: "Gary Derian" Subject: Re: Limited cooling space Certainly, the higher the delta T the higher the heat rejection. It seems to me that its the same with a tall/narrow or low/wide of equal area. Gary Derian > Frederic Breitwieser wrote: > > > > > The way I see it, the coolant now "sees" a radiator that is 1/3 as high and > > > 3 times longer. Why does this cool better than normal. The log delta T is > > > the same, no? Is it a flow turbulence thing? That is the only change I > > > see. > > > > Here would be my guess... > > > > If you increase the width of the radiator, the coolant has to move > > further to reach the other side and be sucked back into the system, > > therefore its exposed to the ambient (and hopefully cooler) air > > temperature, which reduces the temperature of the coolant going back > > in. > > But, heat lost is proportional to the temperature delta. As the water > passes through this longer radiator you dump less and less heat because > the temp delta is getting closer to zero. Maybe Gary can weigh in here > but I think you want the radiator at the highest possible average > temperature to maximize heat transfer. That situation is achieved by > the "parallel" radiator, not the serial radiator. > > > --steve > > -- > Steve Ravet > steve.ravet@xxx.com > Advanced Risc Machines, Inc. > www.arm.com ------------------------------ Date: Wed, 19 May 1999 15:47:06 -0700 From: "Todd....!!" Subject: Re: Mr Helmholz - simple model The way I was taught to roughly but effectively 'tune' my exhaust system on my 4 stroke v-8's engine's is to bolt about a 2 or 3 foot pipe to the header collector paint it black with some spray paint (preferably BEFORE installing the pipe) then do a run down the strip... After runnin the car at WOT for a 1/4, there will be a point on the 'tuning' pipe where the paint has been burned off, and a point further up towards the header where the paint isn't burnt at all! At the point where the paint begins being burnt is where ya cut the pipe.. Whalaa instantly tuned exhaust... I've never heard a technical explanation of why this works or even if it helps or hurts or is just a guess at the correct length of exhaust pipe... But after readin all this about a 2-stroke Mr. Helmholz resonance model and how it's applicable to at least a two stroker... I had to post my 'tuning' rules as passed down to me by a pretty smart engine builder/tuner... Any additional info on the 'tuning' technique I've described above? Thanks for anything! Will most likely be runnin the 97 Stratus with a 4 banger, 4 vlvs/ cyl 2.0 liter automatic to the strip this evenin.... Wanna see what she does before I decide to either keep er or give her back to ol Chrysler... It DEFINITELY beats the HECK outa my 70 Bee as far as gas mileage, but the torque department is lackin a bit.... what's it got like 130 lb ft vs 500+ from the Bee's 440... We'll see... $160+ per month for gas for the Bee vs. MAX $60/month for gas for the Stratus... If she breaks into the 16's this evenin, I'll be pretty happy! Will keep ya'll posted... ALSO, the Stratus' engine cuts off at like 85 mph, would any of ya'll know how to bypass this? It's a speedometer thing, I believe cuz the rpm's aren't much over like 3,000 or so at this speed, the red line is 6,000... so it's not an rpm limiter(Maybe a combination?) Any clues would help tremendously! Thanks! Todd....!! http://www.c-com.net/~atc347/toddlnk.htm Stuart Baly wrote: > > >If this opens a whole new box of problems, just ignore. But, I've noticed > >what a huge change expansion chambers have had of VE in 2 strokes, and > after > >seeing the Mercedes Benz GT (Sedan, whatever they call em) with the v-6, > and > >3 into 1 exhausts, and running 2 expansion chambers (one per side), I just > >wonder, how they came up with that... > > Is it the shape of the cones or volume that makes a "E.C." work, or > >both?. > >Grumpy > > For a blue-smoke, it's the shape more than the volume. Things happen in > this order: > 1. the piston uncovers the exhaust port, sending a pressure pulse along the > exhaust at the speed of sound. The exhaust gas begins travelling along the > pipe somewhat slower than this. > 2. the pressure pulse reaches the expanding part of the exhaust (i.e. > increasing diameter). The change in diameter produces a reflected wave of > lower pressure - this low pressure wave travels back towards the engine. > 3. The piston, still travelling downwards, uncovers the transfer port. F > uel-air mixture starts to displace exhaust gas from the cylinder. > 4. The original pressure pulse reaches the reducing part of the exhaust > (i.e. reducing diameter). This produces a reflected wave of higher > pressure, travelling back towards the engine. > 5. The reflected wave from pt. 2 reaches the engine - this draws the > exhaust mixture from the cylinder, and in extreme cases, even draws some > fuel-air into the exhaust. > 6. The reflected wave from pt4. reaches the engine - this pushes the > fuel-air back into the cylinder just in time for the rising piston to close > the exhaust port off. > > I'm sure that the real world operation of a two-stroke exhaust system has > many many more factors affecting it, and that this is a greatly sanitised > version of reality, but it's a start. > > Stuart Baly. > > Name: WINMAIL.DAT > Part 1.2 Type: unspecified type (application/octet-stream) > Encoding: x-uuencode ------------------------------ Date: Wed, 19 May 1999 15:18:54 -0700 From: "Todd....!!" Subject: Re: Ignition advance, was Re: alternative engines, WARPED My Mopar is setup with 38 degrees TOTAL including mechanical advance, and 56 degrees total including the vacuum advance, the initial timing at the crank does not concern me as long as the mechnical and vac are in line, and they are right in lign with the factory specs... Any more timing than 38 mechanical will cause the thing to ping at acceleration... I set it by ear a while back, then put the timing light to it and foudn that I was at about 38.75 degrees, I had adjusted it so that it wouldn't ping during acceleration, and 38 seems to be the ticket... And I'm pushin 195 to 205 lbs. of air with the compression tester in this 440 even with open chambered heads and totally flat top pistons! (No valve reliefs) I also used the steel shim head gaskets (.022 compressed thickness) With an iddy biddy Mopar purpleshaft 284/.484 hyd cam! No millin or nothin... Go figure! Later! Todd....!! http://www.c-com.net/~atc347/toddlnk.htm Don.F.Broadus@xxx.com wrote: > > The problem with going to manifold vac on some HEI's is that the vac can has > as much as 25 degrees (crank) advance built in. > with say 12 degrees initial you have 37 degrees at idle, then when you > start to get into it the cent. advance starts and the knocken > commences. If you go manifold vac change the can to one with 10 degrees > (crank). Now you have 22 degrees (crank) changing to lighters springs will > bring the cent curve in quicker also. > Don > > > -----Original Message----- > > From: bearbvd@xxx.net] > > Sent: Wednesday, May 19, 1999 8:07 AM > > To: diy_efi@xxx.edu > > Subject: Re: Ignition advance, was Re: alternative engines, WARPED > > > > >At 12:47 PM 5/18/99 -0400, you wrote: > > >>Just use manifold vacuum. Carb vacuum is ported so there is no vacuum > > at > > >>idle. This can help or hurt the idle quality. Try it and see. > > >> > > >>Gary Derian > > >> > > > > > > > > > You sure about that? I have always understood that a vac advance > > can > > >reads ported vacuum in order to affect a curve that begins as the > > throttle > > >is opened and increases as more throttle is applied, up to the point at > > >which all vacuum (manifold and therefore ported as well) fades under > > heavy > > >throttle openings, at which point the advance will decline again and the > > >engine will see only mechanical advance. This is apparently to provide > > >extra advance for economy at part throttle. Anybody who can further > > >illustrate this concept, please do because if I am wrong here I'm going > > to > > >have some serious rethinking to do! > > > > Sorry Aaron-- > > > > Ported vacuum was first used to provide LESS advance at idle so as to > > decrease idle emissions! (But to still keep more like the ideal advance at > > cruise.) > > > > Regards, Greg > > > > > > > > > Aaron Willis > > > ICQ #27386985 > > > AOL IM: hemiyota > > > http://surf.to/garage-te51 Garage TE51 International > > ------------------------------ Date: Wed, 19 May 1999 17:37:42 -0400 From: "Chew, Aaron" Subject: RE: Limited cooling space I would reply the following. I know I could be wrong, but here's my thinking: I think the coffee cup analogy more closely represents comparing the water temp of car with a radiator and a car without it. Of course, the car with the radiator is cooler. I too have trouble believing that the radiator trick results in cooler temps. Sure the water travels through a longer distance, but it sure travels a lot quicker (less time for heat transfer) if the new water pump flow rate can match the original configuration. - -----Original Message----- From: Frederic Breitwieser [mailto:frederic@xxx.com] Sent: Wednesday, May 19, 1999 3:46 PM To: diy_efi@xxx.edu Subject: Re: Limited cooling space > The way I see it, the coolant now "sees" a radiator that is 1/3 as high and > 3 times longer. Why does this cool better than normal. The log delta T is > the same, no? Is it a flow turbulence thing? That is the only change I > see. Here would be my guess... If you increase the width of the radiator, the coolant has to move further to reach the other side and be sucked back into the system, therefore its exposed to the ambient (and hopefully cooler) air temperature, which reduces the temperature of the coolant going back in. While my dilbert-cube-mates think I'm insane, I just tried something that you can do that will illustrate the point. Run the hot water on your faucet for a few minutes, until the temperature is constant. Stick a thermometer into a coffee mug, then fill it with hot water. Record temperature. Then, using a second thermometer, or cool off the first one to room temperature, repeat the experiment, however use the hose with the spray gun, which typically has 5-6 feet of hose under it. The temperature in the mug is consistantly 5-6 degrees colder. I did this 3 times to make sure. Longer hose, more distance traveled, more energy (heat) lost or radiated into "space". - -- 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: Wed, 19 May 1999 17:36:55 -0700 From: rr Subject: Re: O2 Volts Bruce Wrote: >Per several off list letters I checked/doubled checked/thriple checked >grounds and power for this bit of history. > I noted the following, using a 4 wire heated O2 sensor. (General Motors) >With no power to heater, 0.0v. For approximately 30secs 0.0, and then >quickly rose to .1v, then then slowly climbed higher. >When hot, there was a nominal voltage of .28v at the O2 sensor lead wire. >Exposing this sensor to 97% O2 (Medical Grade O2, as tested this am) it >drifted to .030.-.032v. >Exposing this sensor to the Butane from a cigarette lighter that was unlit >immediately responded with a display of .7v...... >Your O2 sensor is a HC Sensor... >Bruce and the staff at CSH, HQ Bruce, I don't know why you say this, if you douse the o2 sensor with butane, you block out the o2, so it will read high, as in a rich fuel mixture. (No o2 present). All of your above sounds correct, and with all respect, the exception of your conclusion... BobR. - -- ------------------------------ Date: Wed, 19 May 1999 17:49:53 -0400 From: "Bruce Plecan" Subject: Re: Limited cooling space - ----- Original Message ----- From: Greg Hermann To: Sent: Wednesday, May 19, 1999 11:54 AM Subject: Re: Limited cooling space Nope, if you remember the Hino show car the Samurii, back from the late 60s early 70s. The firm I worked for converted it to a Fiat Powerplant. Had a massive overheat problem. Much money was spent on all kinds of radiators, including several very expensive ones. The final "trick" is what i discribed, and it worked. Why, I haven't a clue, just that it did. Whatza Aero-K-Whopper??. Bruce > >Someone the other day mentioned having a very confined area for a radiator. > >I just recalled one way of "helping". > >It involves dividing up the radiator so that the coolant rather than just > >going from side to side has to criss cross the radiator several times. > > This is done by adding several barriers internal to the side tanks. On > >the "cold" side of the radiator a divider plate is installed 2/3 of the way > >down from the top, and on the hot side, a divider is added 1/3 of the way > >down, so the coolant has to travel back and forth 3 times rather than once. > > If your out for the gold, you might have to play with the water pump > >speed, some > >Grumpy > > Grumpy-- > > You been checking out the radiator set-up on some of the late model, aero > nose K-Whoppers? > > Greg > > ------------------------------ Date: Wed, 19 May 1999 17:54:30 -0400 From: "Bruce Plecan" Subject: Re: O2 Volts > Bruce Wrote: > >Per several off list letters I checked/doubled checked/thriple checked > >grounds and power for this bit of history. > > I noted the following, using a 4 wire heated O2 sensor. (General Motors) > >With no power to heater, 0.0v. For approximately 30secs 0.0, and then > >quickly rose to .1v, then then slowly climbed higher. > >When hot, there was a nominal voltage of .28v at the O2 sensor lead wire. > >Exposing this sensor to 97% O2 (Medical Grade O2, as tested this am) it > >drifted to .030.-.032v. > >Exposing this sensor to the Butane from a cigarette lighter that was unlit > >immediately responded with a display of .7v...... > >Your O2 sensor is a HC Sensor... > >Bruce and the staff at CSH, HQ > Bruce, I don't know why you say this, if you douse the o2 sensor > with butane, you block out the o2, so it will read high, as in a > rich fuel mixture. (No o2 present). > All of your above sounds correct, and with all respect, the > exception of your conclusion... > BobR. Is butane not a Hydro Carbon?. Bruce ------------------------------ Date: Wed, 19 May 1999 14:57:12 -0700 From: Bill Edgeworth Subject: Re: Limited cooling space There is many things to consider other than the shape of the radiator. The shape in this case may cause higher flow velocity causing more turbulent flow which will greatly increase heat transfer as opposed to laminar flow. Also this is comparing apples to oranges if the two radiators do not have the exact same construction (tube size, fin bonding, fin surface area etc.). Even the hardness of the materials effects thermal conductivity. Bill Edgeworth ------------------------------ Date: Wed, 19 May 1999 16:46:39 -0700 From: "Todd....!!" Subject: Re: 1227749 COOL DEAL Fred!, Thanks for the link man! Looks GREAT! Am learnin bunches mang! Can CLEARLY see that I have a LOT to learn... LATER! Todd....!! Frederic Breitwieser wrote: > > > Sounds like Fred got one of his from a TURBO SUNBIRD... > > That I did! The 7749's are in several vehicles... check Ludis's > detailed site and you can see. I tried to cut and past but for some > reason Windows blew up. > > http://www.cruzers.com/~ludis/p4xref.html#1227749 > > -- > > 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: Wed, 19 May 1999 16:50:20 -0700 From: "Todd....!!" Subject: Re: 1227749 Hey Fred, Thanks for the specs on your rail man! ALSO, what's the HWMMV designation in your list a vehicles at the bottom of your posts? Is it a HUMVIE/HUMMER like Arnold Shwarezzeneggerrrr drives? or what? Thanks! Todd....!! - ----------- Frederic Breitwieser wrote: > > > What diameter and wall thickness was the tubin ya used? > > I used suspension tubing, which is 3/4" outer diameter tubing, with a > inner diameter suitable for threading 1/2", so its slightly less than > 1/2" internal diameter. Buy, clamp, and tap. Couldn't be any easier > for that part. Welding on blocks to mate with the injector was a > little more complex, but not impossible. TIG weld or use > www.durafix.com. I've found out the hard way that MIG welding > aluminum is set aside for welding gods. > > > Aren't they usually billet rails? or are the billet rails just show > > Billet is pretty. But I can polish my aluminum rod, so no big deal. > > -- > > 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: Wed, 19 May 1999 18:26:40 -0400 From: "Ord Millar" Subject: Re: Mr Helmholz - simple model I have heard exactly the same for an H-Pipe. Paint it, and where the paint has blistered up is where the crossover needs to go. - -----Original Message----- From: Todd....!! To: diy_efi@xxx.edu> Date: Wednesday, May 19, 1999 6:20 PM Subject: Re: Mr Helmholz - simple model >The way I was taught to roughly but effectively 'tune' my exhaust system >on my 4 stroke v-8's engine's is to bolt about a 2 or 3 foot pipe to the >header collector paint it black with some spray paint (preferably BEFORE >installing the pipe) then do a run down the strip... > >After runnin the car at WOT for a 1/4, there will be a point on the >'tuning' pipe where the paint has been burned off, and a point further >up towards the header where the paint isn't burnt at all! > >At the point where the paint begins being burnt is where ya cut the >pipe.. Whalaa instantly tuned exhaust... > >I've never heard a technical explanation of why this works or even if it >helps or hurts or is just a guess at the correct length of exhaust >pipe... ------------------------------ Date: Wed, 19 May 1999 18:31:25 EDT From: ECMnut@xxx.com Subject: Re: Mr Helmholz - simple model Todd, if that 4 banger Stratus gives you a 16 second timeslip, it's much stronger than the 17.50 that R&T got ~ a year ago. Let us know how it turns out. Mike V In a message dated 5/19/99 5:28:16 PM Eastern Daylight Time, atc347@xxx.net writes: > > $160+ per month for gas for the Bee vs. MAX $60/month for gas for the > Stratus... > > If she breaks into the 16's this evenin, I'll be pretty happy! > ------------------------------ Date: Wed, 19 May 1999 15:39:01 -0700 From: garfield@xxx.com (Gar Willis) Subject: Re: EGOR, ION, Trionic On Wed, 19 May 1999 11:34:47 -0400 (EDT), "Clive Apps Techno-Logicals 416 510 0020" wrote: >is anyone on this list in the vicintity of Charles City VA >I have a source for a bunch of defective Trionic (SAAB) modules > >you would have to go pick them up HEY! I have a ton of these in BOTH early and late variety. $20ea + shipping and their yours, to anyone who wants one. Course they're unpotted. B) Jim Crance got me my first one; and so the first $20 I get will go to his brewski fund. B) The rest I bought in bulk from a Saab dealer looking to build up his own brewskiNpizza fund. [See, alot of the dealers don't get zip for credit when returning them to Saab, after replacement under warrantee, so if they can sell them for a few bucks, they will usually]. And because they're one ENTIRE FRU (field replaceable unit) due to their being completely encapsulated, if ANYTHING goes bad in the Trionic system, the whole thang's gotta be pulled. Anyhoo, after I finished my own snooping investigation, I figured I'd use the parts outta the remainder, cuz the self-healing AC capacitors they use in the HV section ARE kinda pricey new. But after counting my hours of labor to un-entomb them from the potting, I decided instead I'd MUCH rather buy new ones! But if you wanna go a-sleuthing, and try yer had at the chemotherapy, by all means go for it! After all, hard labor builds character. Plus you just might find some interesting surprises under there. B) Gar ------------------------------ Date: Wed, 19 May 1999 18:50:13 -0400 (EDT) From: "Clive Apps Techno-Logicals 416 510 0020" Subject: Re: Limited cooling space > > Frederic, > I think you are missing a point. If you divide the radiator > into thirds then the water has to flow three times as fast > in each tube to maintain the flow rate. Therefore the time > the water remains in the radiator is the same in both cases. but the extra turbulence may allow more heat to sescape since it destroys the boundary layer(s) Clive ------------------------------ Date: Wed, 19 May 1999 18:51:13 -0400 From: Frederic Breitwieser Subject: Re: 1227749 > Thanks for the specs on your rail man! No problem. People have helped me, I help others, and it all works out in the end. > of your posts? Is it a HUMVIE/HUMMER like Arnold Shwarezzeneggerrrr > drives? or what? Yes, minus the leather, stereo, and original diesel engine. ------------------------------ Date: Wed, 19 May 1999 19:34:10 -0700 From: rr Subject: Re: Ignition advance, was Re: alternative engines, WARPED Bruce (or is that Grumpy?) wrote: >Kinda depends on the WOT pressure drop across the carb., and spring rate of >the vac, advance used. Even with the same no. degrees per amount of vac., >by different spring rates/dia. combinations things could vary. Going from >6-10 start to 20 something at 700rpm, 30 something at WOT (@3,000 rpm), and >40ish at cruise with a OD kinda hard to do thata way (mechanical). Hence >the real beauty of ecm's, IMHO. > Grumpy Bruce is speaking huge amounts of wisdom here, nothing can come close to how an ecm handles spark control. I've installed a '747 ecm and spark control system on a carb'd car, what a difference. Drivability, power, mileage, have all improved. (Yes, I'm still working on the write-up. The cutoff is next week, as I'm going back to school, along with working). Couple of things that mech/vac distrib's aren't/can't do: A 210 point table, based on rpm and manifold vac, that defines the main spark advance value. This in itself blows away any centrif/vac-adv distributor. Startup spark, additional timing added for a short time after the engine is first started. Keeps engine from stalling (choke). Coolant compensation spark, additional timing added/subtracted as a function of engine temp. Hi-way spark, after a set period of time, above a set speed, additional timing added for better mileage. Knock detect and retard, along with testing of the ESC system. PE spark, at WOT, additional fuel is added, and spark is also added to take full advantage. Well, more than a couple, but I hope I can get the idea across. I'm sold on this... BobR. >>| I could be wrong at this, but what I have seen is, ported vacuum is >>dead >>| at idle, because it is above the butterfly....and as throttle is >>increased, >>| vacuum is generated at the "port" and does not go away at full >>| throttle,,,,,great for emissions but terrible for performance,,,,,the same >>| for MPG.... >>| -Carl Summers >>>| You sure about that? I have always understood that a vac advance can >>>| reads ported vacuum in order to affect a curve that begins as the >>>throttle >>>| is opened and increases as more throttle is applied, up to the point at >>>| which all vacuum (manifold and therefore ported as well) fades under >>>heavy >>>| throttle openings, at which point the advance will decline again and the >>>| engine will see only mechanical advance. This is apparently to provide >>>| extra advance for economy at part throttle. Anybody who can further >>>| illustrate this concept, please do because if I am wrong here I'm going >>>to >>>| have some serious rethinking to do! >>>| Aaron Willis ------------------------------ Date: Wed, 19 May 1999 16:49:20 PDT From: "David Sagers" Subject: EGR? What is the purpose of an EGR and why is it used. I'm trying to decide if I should connect the EGR for my street hot rod. _______________________________________________________________ Get Free Email and Do More On The Web. Visit http://www.msn.com ------------------------------ Date: Wed, 19 May 1999 19:47:46 -0700 From: rr Subject: Re: O2 Volts >> Bruce Wrote: >> >Per several off list letters I checked/doubled checked/thriple checked >> >grounds and power for this bit of history. >> > I noted the following, using a 4 wire heated O2 sensor. (General >Motors) >> >With no power to heater, 0.0v. For approximately 30secs 0.0, and then >> >quickly rose to .1v, then then slowly climbed higher. >> >When hot, there was a nominal voltage of .28v at the O2 sensor lead wire. >> >Exposing this sensor to 97% O2 (Medical Grade O2, as tested this am) it >> >drifted to .030.-.032v. >> >Exposing this sensor to the Butane from a cigarette lighter that was >unlit >> >immediately responded with a display of .7v...... >> >Your O2 sensor is a HC Sensor... >> >Bruce and the staff at CSH, HQ >> Bruce, I don't know why you say this, if you douse the o2 sensor >> with butane, you block out the o2, so it will read high, as in a >> rich fuel mixture. (No o2 present). >> All of your above sounds correct, and with all respect, the >> exception of your conclusion... >> BobR. >Is butane not a Hydro Carbon?. >Bruce (I'm chuckle'ing to myself), you've a point there. I have to head out to the garage, I have, lets see; propane, argon, acytelene (sp!), I'll see about butane. I have to try some things out here... (as Arnie would say, in that low, deep voice, 'I'll be back'). BobR. - -- ------------------------------ Date: Wed, 19 May 1999 19:15:43 -0500 From: steve ravet Subject: Re: EGR? David Sagers wrote: > > What is the purpose of an EGR and why is it used. I'm trying to decide if I > should connect the EGR for my street hot rod. Lots of EGR info in the archives, look there for more. Briefly EGR is "neutral" as far as combustion is concerned. Adding EGR doesn't make the air/fuel mix leaner or richer. It lowers combustion temp (not as much fuel to burn) which helps emissions. It also helps fuel economy by reducing fuel at part throttle conditions. - --steve > > _______________________________________________________________ > Get Free Email and Do More On The Web. Visit http://www.msn.com - -- Steve Ravet steve.ravet@xxx.com Advanced Risc Machines, Inc. www.arm.com ------------------------------ Date: Wed, 19 May 1999 17:25:31 -0700 From: "soren" Subject: Re: O2 Volts >>> Bruce, I don't know why you say this, if you douse the o2 sensor >>> with butane, you block out the o2, so it will read high, as in a >>> rich fuel mixture. (No o2 present). >>> All of your above sounds correct, and with all respect, the >>> exception of your conclusion... >>> BobR. > >>Is butane not a Hydro Carbon?. >>Bruce > >(I'm chuckle'ing to myself), you've a point there. I have >to head out to the garage, I have, lets see; propane, argon, >acytelene (sp!), I'll see about butane. I have to try some >things out here... (as Arnie would say, in that low, deep >voice, 'I'll be back'). So go out, try the argon, and see how it compares to any of the HC gases and the pure O2 that Bruce tried earlier. If the argon/O2 readings are the same, it is a HC sensor. If the argon/HC readings are the same, it is an O2 sensor. Either way, it seems to me as if whichever gas actually produces voltage is the one it is sensing. Soren ------------------------------ Date: Wed, 19 May 1999 20:56:55 -0400 From: "Bruce Plecan" Subject: Re: O2 Volts > >>> Bruce, I don't know why you say this, if you douse the o2 sensor > >>> with butane, you block out the o2, so it will read high, as in a > >>> rich fuel mixture. (No o2 present). > >>> All of your above sounds correct, and with all respect, the > >>> exception of your conclusion... > >>> BobR. > >>Is butane not a Hydro Carbon?. > >>Bruce > >(I'm chuckle'ing to myself), you've a point there. I have > >to head out to the garage, I have, lets see; propane, argon, > >acytelene (sp!), I'll see about butane. I have to try some > >things out here... (as Arnie would say, in that low, deep > >voice, 'I'll be back'). > So go out, try the argon, and see how it compares to any of the HC gases > and the pure O2 that Bruce tried earlier. If the argon/O2 readings are the > same, it is a HC sensor. If the argon/HC readings are the same, it is an O2 > sensor. Either way, it seems to me as if whichever gas actually produces > voltage is the one it is sensing. > Soren That's the whole purpose of my testing. I've read so many versions of reported facts, I'm leery of them all about now. If someone has access to more gases, and can shed more light on this, then either errors in my methodology, will be exposed, or verified. Either way, I/we win. Bruce ------------------------------ Date: Wed, 19 May 1999 21:10:27 -0400 From: "Bruce Plecan" Subject: Re: EGR? > David Sagers wrote: > > What is the purpose of an EGR and why is it used. I'm trying to decide if I > > should connect the EGR for my street hot rod. > Lots of EGR info in the archives, look there for more. > Briefly EGR is "neutral" as far as combustion is concerned. Adding EGR > doesn't make the air/fuel mix leaner or richer. It lowers combustion > temp (not as much fuel to burn) which helps emissions. It also helps > fuel economy by reducing fuel at part throttle conditions. > --steve OK, less heat. Less energy to be recovered. So poorer mileage, and/or performance?. Less pumping losses, but that is a theoretical idea. While some claim that they can run EGR and get better mileage, I at times wonder. I hope to do some testing with some of the digitial fully electronic types, but for the vac., type, I have tested to my satisfaction, that some can open as a result of exhaust Backpressure at High RPM WOT.. Grumpy ------------------------------ Date: Wed, 19 May 1999 21:15:38 -0700 From: rr Subject: Re: O2 Volts >> Bruce Wrote: >>(Some stuff about o2 sensor response's {rr}) Ok, back from the garage, I think you may be on to something here. I put a realsquash heated Bosch o2 sensor, tip down, clamped to the inside of a small can. With the tip below the rim, and the body above. Covered at rim height with plastic sheet (yes it was melting to the sensor) Hooked up twelve volts to the heater, fluke on the output. Nominal volts: ~-40mv in free air, returned to this after each test by fanning above can with piece of paper. Response's to different gases: propane: rapid and long lasting, > 850mv. R12: light response, quick to return to nominal, ~475mv. acetylene: rapid and long lasted, > 750mv. hold breath, breath through tube into can: no effect... argon: light response, very short lived: ~70mv. contact cleaner: medium response, ~650mv. (tricloroethane + diclorodifluoromethane) (couldn't find any butane) Thinking about this, it makes sense. Once you reach stoich (450mv), how can you go higher? Only if the excess hc takes it there... The argon response, or lack thereof, is interesting. Dog-gon-it Bruce, I think you already knew this (yes, I'm chuckle'ing again, as the wife asks 'how the experiments work out'?) BobR. P.S. the epa paper discussed how the o2 sensor was responding to different gases, but there was something hockey about the experiments they were running, but I can't remember what it was. Maybe has to due with the gases they used not being found in an exhaust stream, like the r12 I tried? Can't remember. Gonna' read those sae papers next. - -- ------------------------------ Date: Wed, 19 May 1999 21:32:50 -0400 From: Todd Israels Subject: Re: EGR? At 04:49 PM 5/19/99 PDT, you wrote: >What is the purpose of an EGR and why is it used. I'm trying to decide if I >should connect the EGR for my street hot rod. > > >_______________________________________________________________ >Get Free Email and Do More On The Web. Visit http://www.msn.com > > From my understanding EGR basicaly takes up space and lowers combustion temperature helping emmisions. I am not sure of the effect on detonation if the engine is prone to this but suspect it is not positive. The other effect is lots of carbon(black gunk) buildup in the intake that tends to cause driveability problems when IAC pasages are pluged. I personaly wouldnt use EGR if I dident need to. Todd Israels ------------------------------ Date: Wed, 19 May 1999 21:51:11 -0400 From: "Bruce Plecan" Subject: Re: O2 Volts > >> Bruce Wrote: > >>(Some stuff about o2 sensor response's {rr}) > Ok, back from the garage, I think you may be on to something > here. > I put a realsquash heated Bosch o2 sensor, tip down, clamped to > the inside of a small can. With the tip below the rim, and the > body above. Covered at rim height with plastic sheet (yes it > was melting to the sensor) > Hooked up twelve volts to the heater, fluke on the output. > Nominal volts: ~-40mv in free air, returned to this > after each test by fanning above can with piece of paper. > Response's to different gases: > propane: rapid and long lasting, > 850mv. > R12: light response, quick to return to nominal, ~475mv. > acetylene: rapid and long lasted, > 750mv. > hold breath, breath through tube into can: no effect... > argon: light response, very short lived: ~70mv. > contact cleaner: medium response, ~650mv. > (tricloroethane + diclorodifluoromethane) > (couldn't find any butane) > Thinking about this, it makes sense. Once you reach stoich (450mv), > how can you go higher? Only if the excess hc takes it there... > The argon response, or lack thereof, is interesting. > Dog-gon-it Bruce, I think you already knew this (yes, I'm chuckle'ing > again, as the wife asks 'how the experiments work out'?) > BobR. > P.S. the epa paper discussed how the o2 sensor was responding to > different > gases, but there was something hockey about the experiments they were > running, but I can't remember what it was. > Maybe has to due with the gases they used not being found in an exhaust > stream, like the r12 I tried? Can't remember. > Gonna' read those sae papers next. What I'm really getting clear on, is funded research, ie anything EPA, CARB, or anything related to guberment. They fund to get the desired results, which ain't science in my little part of the world. Grumpy ------------------------------ Date: Wed, 19 May 1999 19:54:12 -0600 From: bearbvd@xxx.net (Greg Hermann) Subject: Re: Limited cooling space >The way I see it, the coolant now "sees" a radiator that is 1/3 as high and >3 times longer. Why does this cool better than normal. The log delta T is >the same, no? Is it a flow turbulence thing? That is the only change I >see. > >Gary Derian What Kenworth is doing is not what is described below--they mount two or three separate radiators, one in front of the other, and pipe them in series, with the warmest coolant going to the rear one, then to themiddle on, then to the front. This gives a closer approximation to a true counterflow heat exchanger. A true counter flow heat exchanger gives a greater log mean temp. difference, and thus performs better. Greg > > >> >Someone the other day mentioned having a very confined area for a >radiator. >> >I just recalled one way of "helping". >> >It involves dividing up the radiator so that the coolant rather than just >> >going from side to side has to criss cross the radiator several times. >> > This is done by adding several barriers internal to the side tanks. On >> >the "cold" side of the radiator a divider plate is installed 2/3 of the >way >> >down from the top, and on the hot side, a divider is added 1/3 of the way >> >down, so the coolant has to travel back and forth 3 times rather than >once. >> > If your out for the gold, you might have to play with the water pump >> >speed, some >> >Grumpy >> >> Grumpy-- >> >> You been checking out the radiator set-up on some of the late model, aero >> nose K-Whoppers? >> >> Greg >> ------------------------------ End of DIY_EFI Digest V4 #294 ***************************** 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".