DIY_EFI Digest Friday, 12 March 1999 Volume 04 : Number 161 In this issue: Re: Real HP loss numbers Schrick VGi /Rpm switch - SOLVED Re: Real HP loss numbers Re: Real HP loss numbers Re: Electric water pumps (was) alt charging cont sw Re: Real HP loss numbers Re: Real HP loss numbers RE: Real HP loss numbers Re: Harnesses are a waste Re: [M] Alterpower alternator charging control switch RE: single injector TBI throttle body needed for 2 liter engine Re: Real HP loss numbers Re: VSS and Transmission Output speed Re: Electric water pumps (was) alt charging cont sw Re: Harnesses are a waste Re: DIY_EFI Digest V4 #160, Eprom Emulator Re: Real HP loss numbers Bosch Fuel Pump Re: Electric water pumps (was) alt charging cont sw Re: Real HP loss numbers Re: Electric water pumps (was) alt charging cont sw Re: Electric water pumps (was) alt charging cont sw Re: Real HP loss numbers Re: Real HP loss numbers Re: Real HP loss numbers Re: Electric water pumps (was) alt charging cont sw Re: Real HP loss numbers See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- From: Roger Heflin Date: Fri, 12 Mar 1999 12:04:06 -0600 (CST) Subject: Re: Real HP loss numbers On Fri, 12 Mar 1999, Dan Llewellyn2 wrote: > I have wondered about this myself. I have heard anywhere from 15% > to 25% in drivetrain losses. What I can't figure out is where the > energy is going. If you have a 300HP engine with 25% drivetrain > loss, then you are losing 75HP somewhere. Since it doesn't just > disappear, something has to be soaking up 75HP of energy. My > guess is that the loss would be in the form of heat which would > mean of lot of drivetrain parts would have to be getting really hot > (assuming the 300HP load on the engine). Since I have only seen > my transmission get warm, it doesn't really make much sense unless > I just haven't had the load on for a long enough period. > > I wonder sometimes if people don't estimate drivetrain losses on the > high side because they don't want to admit that their engines aren't > as powerful as they want them to be. > > Dan L > I have heard of people engine dynoing, and then dynoing the engine in a car (manual tranny) and coming up with 12% for a manual. I don't remember who did the work. The big places to lose the heat are tranny (I don't know how much heat a tranny can dissapate), rear end (again I don't know how much), rear brakes and axle (friction), again no estimate on waste. 75 hp is 55kw so something is dissapating alot of energy, but since we know the radiator is able to dump alot more than 55kw (My engine is rater a 370rwhp, so about 275kw, so the engine is dumping close to 2x that much energy or about 500kw into the radiator/exhaust flow), so the tranny doing around 55 kw or so does not seem that far off. I guess someone needs to put a temp monitor on the tranny and see how much heat is being dumped in it, at least on the heat up you could get some idea how much heat it took to heat it how fast. Roger ------------------------------ From: Jason_Leone@xxx.com Date: Fri, 12 Mar 1999 09:11:39 -0800 Subject: Schrick VGi /Rpm switch - SOLVED Just wanted to let folks know that I solved my variable geometry intake manifold controller problem. The original PCB controller failed, so I scrapped it. I installed my new Summit Racing brand adjustable rpm switch (last night), and all is well. The Schrick VGi manifold is working properly once again. I had to fiddle w/ the DIP switch settings on the PCB though...to get it to open the plenum flap when I wanted it to (4k rpm). Funny how setting the DIPs for 3600 rpm actually triggers the signal at 4k rpm. Must be the difference in tachometer rpm signal. The Summit unit is designed for most domestic ignition systems (points or capacitive discharge), so my Bosch ECU tach signal probably didn't follow their calibration curve. The switch doesn't have a hysteresis function, oh well. The needle never stays exactly at 4k anyway, he he. Doesn't matter, I can spin the wheels through two gears once again. I REALLY have to get my Quaife LSD installed soon. Jason '93 SLC ------------------------------ From: "Bruce Plecan" Date: Fri, 12 Mar 1999 13:10:04 -0500 Subject: Re: Real HP loss numbers - -----Original Message----- From: Dan Llewellyn2 To: diy_efi@xxx.edu> Date: Friday, March 12, 1999 1:03 PM Subject: Re: Real HP loss numbers BINGO, So are many of these chassis dyno HP numbers being claimed, IMHO. Bruce > >I wonder sometimes if people don't estimate drivetrain losses on the >high side because they don't want to admit that their engines aren't >as powerful as they want them to be. >Dan L ------------------------------ From: "Clive Apps Techno-Logicals 416 510 0020" Date: Fri, 12 Mar 1999 13:16:08 -0500 (EST) Subject: Re: Real HP loss numbers > > I have wondered about this myself. I have heard anywhere from 15% > to 25% in drivetrain losses. What I can't figure out is where the > energy is going. If you have a 300HP engine with 25% drivetrain > loss, then you are losing 75HP somewhere. Since it doesn't just > disappear, something has to be soaking up 75HP of energy. My > guess is that the loss would be in the form of heat which would > mean of lot of drivetrain parts would have to be getting really hot > (assuming the 300HP load on the engine). Since I have only seen > my transmission get warm, it doesn't really make much sense unless > I just haven't had the load on for a long enough period. just estimate how much torque it takes to compress a valve spring multiply x 1/2 revs x # springs X length of valve travel x x losses in the vlave gear and add in the amount that it takes to move the valve train components around 15% sounds reasonable on 300 HP that would meav that another 52 HP was being eaten by the engine to move the valves Clive > > I wonder sometimes if people don't estimate drivetrain losses on the > high side because they don't want to admit that their engines aren't > as powerful as they want them to be. > > Dan L > > ------------------------------ From: Frederic Breitwieser Date: Fri, 12 Mar 1999 18:11:21 +0000 Subject: Re: Electric water pumps (was) alt charging cont sw > What did you use for your intercooler in the intake? me An aluminum transmission or oil cooler - forgot which it was... bought it at a local parts store, and sanded off all the paint, brazed it inside the center of the plenum on a homemade aluminum intake, and the airflow went into the top of the plenum, through the cooler, then into the lower area of the plenum which fed the 14-15" runners going to the Buick V6 heads. The only *major* mistake I made is I made the upper plenum and the lower plenum in two pieces, brazed in the cooler, then brazed the top plenum to the bottom plenum. I went a little weld happy, and of course, anything that gets into the intake, will sit on the intercooler and block airflow. And if it leaks, is now a disposable intake. But the concept was pretty good. If you duplicate my efforts, make sure the cooler is removable and of a standard size in case you want to replace it. Welding it all together was pretty stupid. We were in a rush to play. Make it a bolt together system much like the 5.0L intakes - and use gasket sealant. If I go this route for my Dodge truck, I will definately make the plenum(s) in seperate pieces so they can be assembled and disassembled easily. Anyway, the top half of the plenum was an aluminum box, the bottom have was rectangular from a top view, but from a rear/front view (facing the pulleys or the bell housing) the bottom plenum was triangular, and the runners left the triangular bottom at a 90 degree angle to the sides of the triangle heading into the aluminum 3/8" thick head plates, into the heads. I've been meaning to post pictures but I keep forgetting to pick them up from the body shop. Anyway, we experiemented with ice water from an igloo cooler, but over time the water of course heated up and proved not to be a good constant driving solution. Then, we attempted to insert freezer coils from an old freezer into the igloo, which helped maintain a constant temperature of the water, but of course, this required a freezer and a long-ass extension cord if you drive . We hadn't fabricated the freezer compressor to the engine, but the intention was to do so, with an A/C clutch, so that under high power use (WOT), the compressor would be disconnected and use the volume of water as a buffer for a period of time. The draw from the cooler was at the bottom, therefore always taking in colder water than the return feed which was at the top of the cooler. Warm water is always on top, so why not put it there. Anyway, after the basic idea worked, we abandoned the freezer bullshit and started pushing the motor to its limits. The intercooling was provided by a long garden hose that was connected to the sink. The water at the body shop where we had the motor on the dyno has freezing cold well water. - -- Frederic Breitwieser Bridgeport, CT 06606 http://www.xephic.dynip.com 1993 Superchaged Lincoln Continental 1989 500cid Turbocharged HWMMV 1975 Dodge D200 Club Cab (soon to be twin turbo 440) 2000 Buick GTP (twin turbo V6) ------------------------------ From: Roger Heflin Date: Fri, 12 Mar 1999 12:23:21 -0600 (CST) Subject: Re: Real HP loss numbers On Fri, 12 Mar 1999, Clive Apps Techno-Logicals 416 510 0020 wrote: > > > > I have wondered about this myself. I have heard anywhere from 15% > > to 25% in drivetrain losses. What I can't figure out is where the > > energy is going. If you have a 300HP engine with 25% drivetrain > > loss, then you are losing 75HP somewhere. Since it doesn't just > > disappear, something has to be soaking up 75HP of energy. My > > guess is that the loss would be in the form of heat which would > > mean of lot of drivetrain parts would have to be getting really hot > > (assuming the 300HP load on the engine). Since I have only seen > > my transmission get warm, it doesn't really make much sense unless > > I just haven't had the load on for a long enough period. > > > just estimate how much torque it takes to compress a valve spring > multiply x 1/2 revs x # springs X length of valve travel x > x losses in the vlave gear and add in the amount that it takes to > move the valve train components around > 15% sounds reasonable > on 300 HP that would meav that another 52 HP was being eaten by the engine > to move the valves > > Clive > For the 15% number everyone has generally ment the amount of hp lost after the flywheel. The wheel dynos hp nubmer vs. the engine only dyno numbers. So that claim is rear wheel hp * 1.15 (manual tranny) is roughly equal to the engine hp at the flywheel. The valves are the same and already accounted for in both cases. Roger ------------------------------ From: Frederic Breitwieser Date: Fri, 12 Mar 1999 18:21:41 +0000 Subject: Re: Real HP loss numbers > to 25% in drivetrain losses. What I can't figure out is where the > energy is going. If you have a 300HP engine with 25% drivetrain Typically heat. As you accelerate, even if you don't spin your tires, the tires do in fact heat a little bit. Drive at 65 miles an hour for little while in 30 degree weather and touch the tire surfaces - you can actually feel some warmth on the tires. Also, your automatic transmission has many places for losses, and these losses generate heat also, hence the requirement for tranny coolers and such under high loads. Also, your torque converter, when it locks, doesn't quite lock at 100%. Being a fluid based "clamp" so to speak, there are losses in there as well. Also, engine bearing friction, rear seal friction, etc all add up. Even your rear heats the fluid slightly, as you have a mechanical connection (ring and pinion) that as it rotates, generates heat. It makes heat because the teeth intertwine with each other, and the pinion frictionally moves the ring gear around. Some vehicles, especially long-bed trucks, have a split driveshaft going to the rear end, which at the joint of the two shafts, have a giant sperical bearing of some sort. This heats up too :) Heat! > I wonder sometimes if people don't estimate drivetrain losses on the > high side because they don't want to admit that their engines aren't > as powerful as they want them to be. Could be. The only way to really know for sure is to dyno the engine and measure flywheel torque and estimate the HP from there, then do the same at the rear wheels, and compare the two mathematically, then you know what your drivetrain losses are. - -- Frederic Breitwieser Bridgeport, CT 06606 http://www.xephic.dynip.com 1993 Superchaged Lincoln Continental 1989 500cid Turbocharged HWMMV 1975 Dodge D200 Club Cab (soon to be twin turbo 440) 2000 Buick GTP (twin turbo V6) ------------------------------ From: "BUTLER, Tom" Date: Fri, 12 Mar 1999 14:35:10 -0400 Subject: RE: Real HP loss numbers Wouldn't horsepower lost to opening valves be recovered (at least to a large degree) by valves closing? Tom Butler > just estimate how much torque it takes to compress a valve spring > multiply x 1/2 revs x # springs X length of valve travel x > x losses in the vlave gear and add in the amount that it takes to > move the valve train components around > 15% sounds reasonable > on 300 HP that would meav that another 52 HP was being eaten by the engine > to move the valves > > Clive > > > > > > I wonder sometimes if people don't estimate drivetrain losses on the > > high side because they don't want to admit that their engines aren't > > as powerful as they want them to be. > > > > Dan L > > > > ------------------------------ From: "Bruce Plecan" Date: Fri, 12 Mar 1999 13:34:34 -0500 Subject: Re: Harnesses are a waste - -----Original Message----- From: Frederic Breitwieser To: diy_efi@xxx.edu> Date: Friday, March 12, 1999 1:05 PM Subject: Re: Harnesses are a waste Wound up being some misc lighting harnesses.. I was just playing scout on the deal, Bruce >> Hardly worth the money. >> Bought 6 @$5 ($25 min), plus $9+ for S+H = no bargain >I thought this was an efi harness? Sounds like I >misunderstood or there are just a -few- connectors missing. >Frederic Breitwieser ------------------------------ From: Mark_Duewel@xxx.gov Date: Fri, 12 Mar 1999 10:28:55 -0800 Subject: Re: [M] Alterpower alternator charging control switch Great discussion on this thread! Thanks to everyone for the feedback. At this point, I think my best move would be to get rid of the double V-belts and adapt a serpentine belt arrangement, with a slightly smaller crank pulley. Sliding in and out of the "V"s must eat up some power at higher RPMs. - -Mark richard's point is just as valid today as it was however many years ago. pick up a copy of hot rod, muscle mustang, fast ford, etc etc etc and look at the advertisements ... you'll find that several vendors supply under drive pulleys for late model muscle cars, and that 5 to 8 _rear wheel hp_ (!) is the typical gain. this is no bull: these magazines have run _independent_ dyno tests and verified these claims several times. discussion on the list seems to confirm that the loss _from the alternator itself_ should be about 1 or 2 hp ... where does the rest come from? the belts. in a high rpm situation -- be it on a dyno or at the race track -- if you spin the alternator w/ stock pulleys that were designed for 2 -> 3k operation at twice that speed or more, you are going to have some very high losses thru belt hysteries. hey, the oem system was design to live in day to day situations for mom & pop ... barry ------------------------------ From: "Peter Fenske" Date: Fri, 12 Mar 1999 10:30:00 -0800 Subject: RE: single injector TBI throttle body needed for 2 liter engine Hi Ted The slodges were vertically mounted too. I haven't seen any horizontally mounted tbis. lots of port injection but no tbis. Got a dead slodge TBI here if you are close to Van. B.C. :peter ------------------------------ From: Pat Ford Date: Fri, 12 Mar 1999 13:45:20 -0500 Subject: Re: Real HP loss numbers On Fri, 12 Mar 1999, Dan Llewellyn2 wrote: > Date: Fri, 12 Mar 1999 12:52:40 -0500 > From: Dan Llewellyn2 > To: diy_efi@xxx.edu > Subject: Re: Real HP loss numbers > > I have wondered about this myself. I have heard anywhere from 15% > to 25% in drivetrain losses. What I can't figure out is where the > energy is going. If you have a 300HP engine with 25% drivetrain > loss, then you are losing 75HP somewhere. Since it doesn't just > disappear, something has to be soaking up 75HP of energy. My > guess is that the loss would be in the form of heat which would > mean of lot of drivetrain parts would have to be getting really hot > (assuming the 300HP load on the engine). Since I have only seen > my transmission get warm, it doesn't really make much sense unless > I just haven't had the load on for a long enough period. diffs and ujoints get pretty warm ( I've seen thermosenors and coolers on diffs). If I unlock the front hubs on my tracker there is a slight seat of the pants improvement in acceleration > I wonder sometimes if people don't estimate drivetrain losses on the > high side because they don't want to admit that their engines aren't > as powerful as they want them to be. don't most ads proclaim flywheel hp?? > > Dan L > > > Pat Ford email: pford@xxx.com QNX Software Systems, Ltd. WWW: http://www.qnx.com (613) 591-0931 (voice) mail: 175 Terrence Matthews (613) 591-3579 (fax) Kanata, Ontario, Canada K2M 1W8 ------------------------------ From: Shannen Durphey Date: Fri, 12 Mar 1999 13:40:20 -0500 Subject: Re: VSS and Transmission Output speed Peter D. Hipson wrote: > > I'm doing extensive work on the TISS/TOSS senders. No, they are not equal > in pulses per revolution, there is a substantial difference. (I've the > ratios, if that's important...) Sure, pass 'em along for posterity's sake. > The senders are both magnetic coil type, > returning an A/C signal who's frequency (and voltage) varies with the RPM. > The only reason the voltage changes is due to improved efficiency at higher > speeds--the voltage change is not significant to the TCM, for example. Be > aware that common mode noise can be a problem with these senders, as can > bad connectors. As well, the sender itself fails frequently--arrggg! > I think I remember reading or hearing that the VSS signal voltage can get extremely high before conditioning. What voltage levels are you seeing on average and how high do they peak? Shannen > At 11:01 PM 3/11/99 -0500, you wrote: > >Hi, Dr. Plecan. > > > >4L80E trans has 2 speed sensors installed, Transmission Input Shaft > >Speed and Transmission Output Shaft Speed. Early 4wd (pre94) had > >separate VSS and dedicated signal to PCM, 2wd and 94+4wd didn't have > >extra sensor so combined the signals. > > > >TOSS is used for gear ratio calculations, VSS is used for shift > >control. TISS is used for TCC control, shift pattern, shift quality. > > > >I remember a few codes for these, trans component slipping, tcc apply > >error, undefined gear ratio, excessive shift times. > > > >Nothing I have gives # of pulses/rev, but I think the frequency is > >different between the two shafts, due to different "wheel" diameters. > >Definitely A/C from the sensor, as they are the same part no. TISS > >must be conditioned inside the PCM, TOSS may depend on the year of the > >calibration. Kinda makes the electronic > >simulations a job for the entire CSH staff... > >Shannen > > > >Bruce Plecan wrote: > >> > >> On a 8625 pcm, there are two connections, one labeled VSS, which is vehicle > >> speed sensor, and a second one labeled transmission output speed, they > >> both feed from the Vehicle Speed Signal Bufffer to the PCM. Can anyone > >> splain this to me?. Is this just a way of checking for transmission > >> "slippage". > >> Anyone happen to know what this 5v signal should be?. ie square, > 4,000ppm?. > >> Thanks > >> Bruce > > > > > > > Thanks, > Peter Hipson (founder, NEHOG) > 1995 White NA Hummer Wagon ------------------------------ From: ScottyCBoy@xxx.com Date: Fri, 12 Mar 1999 13:49:54 EST Subject: Re: Electric water pumps (was) alt charging cont sw In a message dated 03/12/1999 10:07:55 AM Pacific Standard Time, clive@xxx.com writes: << > > > > It is useful to have an electric water pump, but I believe drag race > is about the only use. There are several people (on the f-body list > with electric pumps), that say that the do not flow enough for road > racing, so that needs to be kept in mine when looking at one. It may > comprimise being able to use the vehicle as a daily drive or a road > race vehicle. If I was only drag racing, I would have an electric. some guys have used things like marine bilge pumps they are trubine style pumps with a strait trhough flow path can move massive amounts of water with the larger sizes should be no reason no to use one of these Clive >> I have pondered the us of electric water pumps and I believe that they would be beneficial in many ways: First no thermostat would be needed, when the engine get's to operating temp the pump would turn on.. Second the pump can run at varying speeds, while light cruising the pump speed would be slower than at full steam, saving fuel.. Thrid the engine could theoretically warm up quicker as there would be no leak past a closed thermostat and coolant wouldn't be circulating through a cold engine... Fourth reverse flow coolant systems could be retorfitted easily just by reversing the current to the pump, no special reverse flow pump impellers would be needed... Scott ------------------------------ From: Frederic Breitwieser Date: Fri, 12 Mar 1999 18:44:34 +0000 Subject: Re: Harnesses are a waste > Wound up being some misc lighting harnesses.. I was just playing scout > on the deal, Sorry that deal sucked. I was almost ready to order an EFI harness LOL - -- Frederic Breitwieser Bridgeport, CT 06606 http://www.xephic.dynip.com 1993 Superchaged Lincoln Continental 1989 500cid Turbocharged HWMMV 1975 Dodge D200 Club Cab (soon to be twin turbo 440) 2000 Buick GTP (twin turbo V6) ------------------------------ From: "Mark D'Sylva" Date: Fri, 12 Mar 1999 14:00:44 -0800 Subject: Re: DIY_EFI Digest V4 #160, Eprom Emulator > ------------------------------ > > From: Pat Ford > Date: Fri, 12 Mar 1999 13:02:25 -0500 > Subject: eprom emulator > > Hi There: > I just found a url for an eprom emulator > http://space.tin.it/computer/lorgler/nonst-e.html > > > > Pat Ford email: pford@xxx.com > QNX Software Systems, Ltd. WWW: http://www.qnx.com > (613) 591-0931 (voice) mail: 175 Terrence Matthews > (613) 591-3579 (fax) Kanata, Ontario, Canada K2M 1W8 > > ------------------------------ Pat, I attempted to look at the link (just curious) and it was dead. You don't have to order eprom emulators all the way from Italy. Many places in USA sell them. I think even Universal Cross Assemblers in Canada sells one. For anyone who is interested, here are a few vendors of ROM emulators: Dataman: the Dataman S4 is a programmer and emulator: www.dataman.com Grammar Engine: Promice with trace: www.gei.com EmuTec: PromJet emulator: www.emutec.com I think TechTools (www.tech-tools.com) may also sell rom emulators Mark D'Sylva ------------------------------ From: goflo@xxx.net Date: Fri, 12 Mar 1999 12:09:15 -0800 Subject: Re: Real HP loss numbers Drive train losses are dissipated as heat, which is'nt impossible to keep track of on a chassis dyno - A drive train dissipating 20-30% of big HP oughta be glowing in the dark... Jack Bruce Plecan wrote: > BINGO, > So are many of these chassis dyno HP numbers being claimed, IMHO. > >I wonder sometimes if people don't estimate drivetrain losses on the > >high side because they don't want to admit that their engines aren't > >as powerful as they want them to be. > >Dan L ------------------------------ From: Clarence Wood Date: Fri, 12 Mar 1999 13:10:33 -0600 Subject: Bosch Fuel Pump Can anybody help me find out anything about this pump: Bosch: 9 580 810 020 12V. 562-10 E7TF.9350.AA 5B10 Thanks Clarence IZCC #3426 1982 280ZX Turbo GL 1966 El Camino 1982 Yamaha Maxim XJ-1101J Motorcycle 1975 Honda CB750 SS (black engine) 1986 Snapper Comet lawn mower Clarence Wood Software&Such... clarencewood@xxx.net Savannah, TN. ------------------------------ From: Roger Heflin Date: Fri, 12 Mar 1999 13:08:19 -0600 (CST) Subject: Re: Electric water pumps (was) alt charging cont sw On Fri, 12 Mar 1999 ScottyCBoy@xxx.com wrote: > > some guys have used things like marine bilge pumps > they are trubine style pumps with a strait trhough flow path > can move massive amounts of water with the larger sizes > should be no reason no to use one of these > > Clive >> > > I have pondered the us of electric water pumps and I believe that they would > be beneficial in many ways: > > First no thermostat would be needed, when the engine get's to operating temp > the pump would turn on.. > Probably you would need a thermostat to regulate the varing speeds, the hotter the engine gets that faster the pump goes. I know there are some computers that regulate their fans this way. > Second the pump can run at varying speeds, while light cruising the pump speed > would be slower than at full steam, saving fuel.. > > Thrid the engine could theoretically warm up quicker as there would be no leak > past a closed thermostat and coolant wouldn't be circulating through a cold > engine... Someone was told by a manufacturer of one of those pumps that it was not wise to not run the pump when the engine was running as hot spots can form rather quickly and damage things. > > Fourth reverse flow coolant systems could be retorfitted easily just by > reversing the current to the pump, no special reverse flow pump impellers > would be needed... > The heads/water ports are designed differently to flow the other direction, so you cannot always just change the water direction and be done with it, the ports are not always designed to flow both ways correctly. The LT1 engines have an entirely differnt water port design so they flow correctly in the other direction. My assumption is that the normal chevy SB water ports won't flow optimally in the reverse direction. > Scott > Roger ------------------------------ From: Roger Heflin Date: Fri, 12 Mar 1999 13:16:32 -0600 (CST) Subject: Re: Real HP loss numbers On Fri, 12 Mar 1999 goflo@xxx.net wrote: > Drive train losses are dissipated as heat, which is'nt impossible > to keep track of on a chassis dyno - A drive train dissipating > 20-30% of big HP oughta be glowing in the dark... > > Jack > > Bruce Plecan wrote: > > BINGO, > > So are many of these chassis dyno HP numbers being claimed, IMHO. > > > >I wonder sometimes if people don't estimate drivetrain losses on the > > >high side because they don't want to admit that their engines aren't > > >as powerful as they want them to be. > > >Dan L > > There is also the question of how much of the hp lost is a percent of the total hp going through the system, and how much is fixed, ie double the hp of the engine, but still the same hp is lost in a certain component. I suspect things like brake rotors lose the same hp, since hp would not seem to affect that friction. So if a certain car with a 300 hp engine loses 12% (36hp), you do not necessarly know that the same car with a 400 hp engine will still loose 12% (48hp). You can probably be fairly sure that the loss is between 36hp and 48hp unless there is some part that loses hp in a nonlinear manner. From what few numbers I have see the more reasonably numbers are more like 12% for a manual and 17% for an auto, but as I mentioned above these are at a given hp level, and the actual numbers could differ by a number of hp. Roger ------------------------------ From: Shannen Durphey Date: Fri, 12 Mar 1999 14:10:25 -0500 Subject: Re: Electric water pumps (was) alt charging cont sw Here we go. Let's use an electric clutch on the fan pulley, temp controlled, wot disable, high water temp override. Hmm.. but probably don't want to run with pump sitting still so adding viscous coupling could keep it spinning some, until the electric unit engages. Or wait! Hydraulically driven, PWM modulated off the power steering pump! That's it! Fixed volume flow when solenoid is closed for minimum rotation, electric failure causes open solenoid and full flow so no overheat. Now I've just got to find a hydraulic motor. (My bid for CSH of the day ends here.) 'Course all this could be done electrically if a motor capable of providing enough water pump speed were used. The electric motors I see driving waterpumps are pretty small, and really underdrive the unit through pulley reduction. If we're using electronic speed control, is there any reason we can't use a more powerful motor and, uhh, reduce the reduction? The stuff I see is on drag cars, and I'm sure they want to keep current draw to a minimum since there's no alternator, either. But with a street car (or old Dodge truck), we'd have the alternator to keep the system charged. I'm actually thinking this will work. Motor selection is the key here, methinks. Uhh.. hold on, I'll be right back. I think the coffee's done. : ) Shannen Roger Heflin wrote: > > On Fri, 12 Mar 1999, Glen Beard wrote: > > > Frederic Breitwieser wrote: > > > > > > you should see what a diff an electric sater pump makes > > > > some stock pumps use more than 30 HP at redline on a revver > > > > > > I've heard this, however never had the courage to venture into this method. I've > > > always been afraid that the alternator would go, and the pump would slow down and > > > not cool properly. Probably a silly fear, since the EFI systems I slap on > > > everything run off the alternator too. No voltage, no anything, not just water. > > > > Now water pumps... I believe that electric water pumps are worth more than just HP. > > You can run them whit the electric fans in the staging lanes to cool the motor. > > > > Don't the dragsters run the 1/4 w/o a water pump at all? You could turn it off just > > before the run. > > > > It is useful to have an electric water pump, but I believe drag race > is about the only use. There are several people (on the f-body list > with electric pumps), that say that the do not flow enough for road > racing, so that needs to be kept in mine when looking at one. It may > comprimise being able to use the vehicle as a daily drive or a road > race vehicle. If I was only drag racing, I would have an electric. > > Roger ------------------------------ From: "Bruce Plecan" Date: Fri, 12 Mar 1999 14:27:16 -0500 Subject: Re: Electric water pumps (was) alt charging cont sw - -----Original Message----- From: Roger Heflin To: diy_efi@xxx.edu> Date: Friday, March 12, 1999 2:17 PM Subject: Re: Electric water pumps (was) alt charging cont sw Moroso sold a kit for reverse flow conversions on the SBC. Not enough HP for the expense.. OEM castings used. Bruce > >The heads/water ports are designed differently to flow the other >direction, so you cannot always just change the water direction and be >done with it, the ports are not always designed to flow both ways >correctly. The LT1 engines have an entirely differnt water port >design so they flow correctly in the other direction. My assumption >is that the normal chevy SB water ports won't flow optimally in the >reverse direction. >> Scott > ------------------------------ From: Daniel Ciobota Date: Fri, 12 Mar 1999 13:27:39 -0600 Subject: Re: Real HP loss numbers Let me jump in on this discussion with an observation. Rear wheel hp numbers are measured by observing the acceleration of two 1000lb drums by the driving wheels of the car. That's how hp is calculated, rotational speed vs. time, known weight of 2000lbs and known drum diameter. From those numbers, and final gear ratios (rpm/drum rotation), the chassis dyno calculates instantaneous torque required to accelerate the drum at that rate. The key measurement here is rotational mass. That parameter affects how fast those drums will accelerate, and since it's a known quantity for the chassis dyno, accurate hp numbers at the driving wheels can be calculated. To backtrack flywheel hp from driving wheel hp, a couple of parameters are most important: frictional loss, as discussed here already, and _rotational mass_, more accurately, momentum. Take for example an aluminum flywheel and the equivalent steel version. In my stang, the aluminum piece weighed 10lbs, while the steel piece was 23lbs. In neutral, the aluminum flywheel accelerated significantly faster than the steel piece; no surprises there. The same concept applies to the rotating pieces inside transmissions, driveshafts and rear ends; the total momentum affects how fast the drive wheels can accelerate, thus affecting rear wheel hp numbers. From observation of different dynoed cars, I think that gm transmissions have slightly less momentum and frictional loss than their ford counterparts. And, of course, because of the fluid and rather massive torque converters, automatics are significantly more sluggish and offer more loss. So, when someone is talking about a 75hp loss, not all that loss is friction, otherwise our drivetrains would glow in the dark! However, much of the loss due to momentum is taken up by the engine (more strain), which shows up as heat in the coolant and oil. If my physics are wrong, please correct me. Just my $0.02. Daniel Roger Heflin wrote: > On Fri, 12 Mar 1999, Clive Apps Techno-Logicals 416 510 0020 wrote: > > > > > > > I have wondered about this myself. I have heard anywhere from 15% > > > to 25% in drivetrain losses. What I can't figure out is where the > > > energy is going. If you have a 300HP engine with 25% drivetrain > > > loss, then you are losing 75HP somewhere. Since it doesn't just > > > disappear, something has to be soaking up 75HP of energy. My > > > guess is that the loss would be in the form of heat which would > > > mean of lot of drivetrain parts would have to be getting really hot > > > (assuming the 300HP load on the engine). Since I have only seen > > > my transmission get warm, it doesn't really make much sense unless > > > I just haven't had the load on for a long enough period. > > > > > > just estimate how much torque it takes to compress a valve spring > > multiply x 1/2 revs x # springs X length of valve travel x > > x losses in the vlave gear and add in the amount that it takes to > > move the valve train components around > > 15% sounds reasonable > > on 300 HP that would meav that another 52 HP was being eaten by the engine > > to move the valves > > > > Clive > > > > For the 15% number everyone has generally ment the amount of hp lost > after the flywheel. The wheel dynos hp nubmer vs. the engine only > dyno numbers. So that claim is rear wheel hp * 1.15 (manual tranny) > is roughly equal to the engine hp at the flywheel. The valves are > the same and already accounted for in both cases. > > Roger ------------------------------ From: "Bruce Plecan" Date: Fri, 12 Mar 1999 14:30:07 -0500 Subject: Re: Real HP loss numbers - -----Original Message----- From: A70Duster@xxx.com> To: diy_efi@xxx.edu> Date: Friday, March 12, 1999 5:03 AM Subject: Real HP loss numbers Maybe locked up reach 97%. More commonly 10% slippage. For a real low po car maybe 6. If ya get drgstrip plus off of the ftp you can play with converter slippage. Bruce >Was wondering (induced by all the talk with computers recording spark signals >and computing HP) what are the actually losses in drivetrain. I've heard the >torque converter is 97% efficient at part throttle and 2 hp at U-joints (I >don't believe, that's 1500 Watts at each joint). Looking at tranny (auto and >standard) u-joints, ring and pinion, bearings, spider gears, axles.... >Sorry, it's off the beaten path, oh well :) >Mike ------------------------------ From: Eric Schumacher Date: Fri, 12 Mar 1999 11:28:57 -0800 Subject: Re: Real HP loss numbers VW gave out some transmission loss numbers a few years ago that were doubly interesting. 28 hp for the longitudinal engined cars Fox etc and 19 hp for the transverse engined cars Rabbit, Jetta etc. The numbers are even more useful since both cars are extremely similar in most regards, use the same engines and are designed by the same team. In further support of this my dad used to race model cars that ran on a tether and they had two classes, one for spur geared cars and another for bevel geared cars. Lotsa Luck Eric 85 GTI with VR6 power ------------------------------ From: steve ravet Date: Fri, 12 Mar 1999 13:36:58 -0600 Subject: Re: Electric water pumps (was) alt charging cont sw > > I have pondered the us of electric water pumps and I believe that they would > be beneficial in many ways: > > First no thermostat would be needed, when the engine get's to operating temp > the pump would turn on.. The pump has to run all the time, you don't want water sitting still inside the block. It'll boil away from the cylinder walls before it even gets warm wherever your temp sensor is. When the thermostat is closed on a normal engine there is still water flowing through the engine, either out thru the heater core and back in, or through a bypass in the water pump or something. > > Second the pump can run at varying speeds, while light cruising the pump speed > would be slower than at full steam, saving fuel.. makes sense. > > Thrid the engine could theoretically warm up quicker as there would be no leak > past a closed thermostat and coolant wouldn't be circulating through a cold > engine... see above... > > Fourth reverse flow coolant systems could be retorfitted easily just by > reversing the current to the pump, no special reverse flow pump impellers > would be needed... isnt' there more to reverse flow than just turning the pump backwards? reverse rotation water pumps have been around since they came up with serpentine belt drives, but they still made some weird cam driven pump for the reverse flow LT1. - --steve > > Scott - -- Steve Ravet steve.ravet@xxx.com Advanced Risc Machines, Inc. www.arm.com ------------------------------ From: Shannen Durphey Date: Fri, 12 Mar 1999 14:36:44 -0500 Subject: Re: Real HP loss numbers Ahh. There was an article (maybe super Chevy?) on valve spring testing done by Isky cams. They use a block with no pistons or rods, no plugs, and power it electrically. The cam, oil pump, and valvetrain are installed. Oil temps still get to 210 deg even though there is no combustion taking place. And the noise level was suprisingly high, too. Gives a guy a little more respect for valve springs. Clive Apps Techno-Logicals 416 510 0020 wrote: > > > > > I have wondered about this myself. I have heard anywhere from 15% > > to 25% in drivetrain losses. What I can't figure out is where the > > energy is going. If you have a 300HP engine with 25% drivetrain > > loss, then you are losing 75HP somewhere. Since it doesn't just > > disappear, something has to be soaking up 75HP of energy. My > > guess is that the loss would be in the form of heat which would > > mean of lot of drivetrain parts would have to be getting really hot > > (assuming the 300HP load on the engine). Since I have only seen > > my transmission get warm, it doesn't really make much sense unless > > I just haven't had the load on for a long enough period. > > just estimate how much torque it takes to compress a valve spring > multiply x 1/2 revs x # springs X length of valve travel x > x losses in the vlave gear and add in the amount that it takes to > move the valve train components around > 15% sounds reasonable > on 300 HP that would meav that another 52 HP was being eaten by the engine > to move the valves > > Clive > > > > > > I wonder sometimes if people don't estimate drivetrain losses on the > > high side because they don't want to admit that their engines aren't > > as powerful as they want them to be. > > > > Dan L > > > > ------------------------------ End of DIY_EFI Digest V4 #161 ***************************** 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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