DIY_EFI Digest Monday, May 3 1999 Volume 04 : Number 259 In this issue: Re: atomization enhancement Re: NC hybrid setup/coolant blows heater core/how to avoid? Crank position sensor relocation query. Re: Toyota management mod limitations?? Re: valve job question Re: NC hybrid setup/coolant blows heater core/how to avoid? Re: Need Fuel Injector Data Re: NC hybrid setup/coolant blows heater core/how to avoid? Re: valve job question Re: valve job question Re: Fuel injection plugs Re: Fuel injection plugs Dodge Intake Construction Re: Flame - Not (Tornado engine?) High economy, was Fuel injection plugs Re: Transplant TPS Re: valve job question Re: Fuel injection plugs Re: Transplant - Bearings Espen's Reed Valves Re: Flame - Not Re: atomization enhancement Re: Direct Injection - Stratified Re: Fuel injection plugs Re: Transplant - Bearings Re: NC hybrid setup/coolant blows heater core/how to avoid? Re: atomization enhancement See the end of the digest for information on subscribing to the DIY_EFI or DIY_EFI-Digest mailing lists. ---------------------------------------------------------------------- Date: Sun, 02 May 1999 15:34:58 -0400 From: "David A. Cooley" Subject: Re: atomization enhancement At 01:21 PM 5/2/99 -0600, you wrote: > >BINGO, Dave!! > >Not to mention that this approach to fuel vaporization is thermodynamically >far less efficient than ATOMIZATION! Using the latent heat of the fuel to >cool the inlet valve, only so the valve can rob heat from the next power >stroke to heat back up is a thermal inefficiency. Letting the latent heat >of well atomized fuel make the compression process in the cylinder more >nearly isothermal than adiabatic increases net power output by reducing the >amount of work which the engine must do during the compression stroke! I would presume thebest of both worlds for efficiency and power would be to have injectors large enough to be able to inject all the fuel needed for each stroke while the valve was open... Atomized fuel enters the combustion chamber with the air. Problems come at low RPM/load situations where the injector is now too large to flow small quantities efficiently... How about 2 injectors per cyl, say a 10lb/hr and a 60 lb/hr, the 10 is used for idle, the larger is slowly phased in as RPM/load increases to keep the total injection squirt during the valve open time. =========================================================== David Cooley N5XMT Internet: N5XMT@xxx.net Packet: N5XMT@xxx. Member #7068 Sponges grow in the ocean... Wonder how deep it would be if they didn't?! =========================================================== ------------------------------ Date: Sun, 2 May 1999 13:57:43 -0600 From: bearbvd@xxx.net (Greg Hermann) Subject: Re: NC hybrid setup/coolant blows heater core/how to avoid? >Howard, I don't know any data specific terms to the heater core failures my >southern friends experienced (I'm in BC and they're all in the US) but it >always went during a WOT dust off of some other hipo car. They replaced >initially w/ junkyard units, they failed, then with several Nissan units to >find they failed under same circumstances. My inexperienced slant at it is >they had a far higher volume/flow than that heater core would normally >experience d/2 their rate of acceleration/ hybrid chevy systems/ and most >likely the Nissan pumps weren't designed for this flow. If not designed >for that flow and given much higher flow than OEM it could create higher >pressure than they were designed for given their has to be restrictions in >the heater core system leading to this pressure increase (if flow isn't >accomodated pressure goes up). I agree w/ you that static pressure as you >described shouldn't be a problem as the systems are very similar in design >pressures and all related components were in as new condition. > Your evaluation is spot on, Ross! If the higher pump head pressure from the larger, faster turning water pump did not get the cores immediately, the pitting corrosion from the higher flow velocities than intended would get them before too long. Regards, Greg ------------------------------ Date: Sun, 02 May 1999 21:25:11 +0100 From: Chris Wilson Subject: Crank position sensor relocation query. I am running a Honda Mugen Formula 3 single seater race engine,in a chassis that is much later than the power unit.I have an interference problem,with the exotically materialed and manufactured primary pipes fouling an adaptor on the back of the exhaust cam,that acts as a crank position sensor.The management system is Mugens own,and this adaptor is a coil,with a ferrite core.Across the end of the core rotates a drum,with an iron segment moulded into it.The whole assembly is mounted in a die cast casing,that bolts to the back of the exhaust cam housing.The primaries foul this casing,quite severely.I either remake the primaries,which are in titanium,and a work of art,or I move the crank position sensor.The inlet cam has the distributor,with a toothed wheel sender also within it,to give RPM readings,bolted to the back of the cam housing,opposite the position sender.Where does the team suggest I could get a crank position signal from? Any neat ideas? Thanks. - -- Best Regards, Chris Wilson. http://www.maximum-bhp.u-net.com ------------------------------ Date: Sun, 2 May 1999 21:42:56 +0100 From: "Chris Wilson" Subject: Re: Toyota management mod limitations?? - ----- Original Message ----- From: WILMAN To: Sent: Friday, April 30, 1999 1:38 AM Subject: Re: Toyota management mod limitations?? > Try gems@xxx. They do an " Implant" for Toyota ECU's which then > allow them to be programmable. OK,thanks,they are a UK firm,so handy for us.We will check this out.Appreciative of the information,cheers. ------------------------------ Date: Sun, 2 May 1999 17:18:34 -0400 (EDT) From: William T Wilson Subject: Re: valve job question On Sun, 2 May 1999, Stowe, Ted-SEA wrote: > In my younger days when doing valve jobs for customers cars, I would clean > off the carbon that was on top of the cylinders. I used to rotate the engine > around and bring the pistons up to tdc and whirl away with a drill bit > mounted wire brush. The problem with this is that it will drop little bits of carbon goop down between the piston and the cylinder, where they will make things sad. This is not the end of the world, but it doesn't do it any good, either. Cleaning the carbon deposits off of the piston isn't really all that important because they just come right back when the engine runs the next time. Last time I had the head off an engine, I used a little scraper tool to scoop all the gunk onto the center of the piston, where I can vacuum it up. No gunk in the cylinder. > should I leave it alone, ? You may as well, unless there's a whole bunch of it. ------------------------------ Date: Sun, 2 May 1999 17:54:32 -0700 From: "Walter Sherwin" Subject: Re: NC hybrid setup/coolant blows heater core/how to avoid? >The pressure head which the water pump generates is proportional to the >square of the pump rpm, and at , say, 5000 pump rpm, for a pump with an >impeller the size of most water pumps, it would not be unreasonable to >expect to see 25 or 30 psi of pressure in the water jackets in ADDITION the >pressure from the radiator cap!! And if the thermostat restriction is >removed, the water pump will cavitate due to not having enough NPSH at the >resulting (higher flow at less developed head) point on its curve for that >particular impeller speed! > >Regads, Greg > Greg, what you say here is quite correct. A couple of years ago, we flogged a near stock BBC (with stock serpentine water pump) for several days on a well equipped dyno. One of the measured parameters was the post pump water jacket pressure. We were quite surprised to observe approximately 55psig of "head" (from a 15psig baseline) at 5000 engine RPM. Post examination of the data revealed the expected speed/pressure curve of a generic centrifugal pump. Walt. ------------------------------ Date: Sun, 2 May 1999 18:15:32 -0700 From: "Walter Sherwin" Subject: Re: Need Fuel Injector Data Take a peek at Saturn injector 17109717, from the 1.9Litre engine, or 17109718 from same. They are both low impedance, and around 17 #/Hr @ 44 psig. Good Luck! Walt. >A friend of mine and I are working on an unusual project. We are adapting a >'93 Saturn ECM and two DIS modules to run a Continental O-200 aircraft >engine. The engine is 200 C.I. (3.3 L) 4 cylinder dual plug and should make >about 120 HP at about 2800 RPM. > ------------------------------ Date: Sun, 02 May 1999 18:56:01 -0400 From: Shannen Durphey Subject: Re: NC hybrid setup/coolant blows heater core/how to avoid? Ross Corrigan wrote: > thanks again for all this feedback, I"m going to gather them up as a FAQ to > post on my page eventually for us ZV8's. > > FWIW, their Datsun heater cores were 20+ yrs old and functioning fine when > they first went, no quality problems their. Ross, what kind of car is this? I ran SB Chevy (several, actually) in a 240Z and never experienced a problem. WOT dustoff?? When do you need WOT?? ; ) Shannen ------------------------------ Date: Sun, 02 May 1999 19:02:02 -0400 From: Shannen Durphey Subject: Re: valve job question Stowe, Ted-SEA wrote: > > should I > > spray some chemical thing on the top and leave it then wipe it all away , > then most likely leave some lubricant in the cylinders. > > thanks, Ted Stowe For about 8 bucks, you can get GM Top Engine Cleaner in a can. Pour some into each cylinder and allow it to sit overnight, then most of the carbon will wipe off. Avoid getting it on your hands, don't run the car without changing the oil after the treatment. Shannen ------------------------------ Date: Sun, 02 May 1999 19:23:35 -0400 From: Shannen Durphey Subject: Re: valve job question William T Wilson wrote: > > On Sun, 2 May 1999, Stowe, Ted-SEA wrote: > > > In my younger days when doing valve jobs for customers cars, I would clean > > off the carbon that was on top of the cylinders. I used to rotate the engine > > around and bring the pistons up to tdc and whirl away with a drill bit > > mounted wire brush. > > > Cleaning the carbon deposits off of the piston isn't really all that > important because they just come right back when the engine runs the next > time. Sounds like a tire shop I went to once. "No need to clean the mud off the wheel before we balance it. It just gets muddy again anyway." Shannen ------------------------------ Date: Sun, 02 May 1999 19:37:55 -0400 From: Shannen Durphey Subject: Re: Fuel injection plugs Howard Wilkinson wrote: > > Greg: > I've personally seen irrigation pump motors run on propane over > 10K hrs. This is a considerably different environment than a farm > truck. > It is unfortunate that the Holly, > Motorcraft, and Autolight carb familys used neoprene diaphragms in > accelerator pumps and in power valves.... they don't like today's gas > at all. There's a simple modification for Holley carbs that prevents power valve damage due to backfire, and the pump diaphragms can be replaced without complete o'haul. > Personally I feel that of the 4 bbl carbs available, the plain old > Quadrajet would have had the most potential of any of them if they had > only made replaceable secondary orfices.... once these are worn > there's nothing to be done. Around 1985 a company called "The Carburetor Shop" offered a kit designed to replace the secondary metering jets. Generally I see worn rods, not jets. Most common seems to be a "ring" worn around the rod caused by the rods "rattling" in the stainless plates that make up the jets. > I've built a puller and removed them, and Puller? I have a drill bit that I've ground to cut the aluminum carb away from the jet, then a small pick easily pulls the exposed jet. > I suppose you could manufacture a replacement, I pull the replacement jet from an unused Q jet. I buy the carbs cheap and strip them for parts. Shannen ------------------------------ Date: Sun, 2 May 1999 20:06:52 -0400 From: "Bruce Plecan" Subject: Re: Fuel injection plugs Your saying you've had the secondary metering rod orfices go bad?. By how much?.... Never saw any worn enough that that worried me. Finding the optimum opending for the secondary air valve was the PITA for me. Well right after digging up all the metering rod hangers, and many needles. Then I built a jig for blueprinting the hangers.. Once ya got the idle jet, idle channel restrictor right then ya could play with the primary idle bypasses. Then you just had to diddle with the primary jets, and dancing needles (ecm content). Had one on a LG4 auto that ran 15.0s, and got 30+mph on the freeway. Same metering also ran 13's on a 355 (crossfire manifold sorta) Grumpy > > Quadrajet would have had the most potential of any of them if they had > > only made replaceable secondary orfices.... once these are worn > > there's nothing to be done. > Around 1985 a company called "The Carburetor Shop" offered a kit > designed to replace the secondary metering jets. Generally I see worn > rods, not jets. Most common seems to be a "ring" worn around the rod > caused by the rods "rattling" in the stainless plates that make up the > jets. > > I've built a puller and removed them, and > Puller? I have a drill bit that I've ground to cut the aluminum carb > away from the jet, then a small pick easily pulls the exposed jet. > > I suppose you could manufacture a replacement, > I pull the replacement jet from an unused Q jet. I buy the carbs > cheap and strip them for parts. > Shannen ------------------------------ Date: Sun, 02 May 1999 21:35:39 -0400 From: Frederic Breitwieser Subject: Dodge Intake Construction Not too exciting, but I started building the plenum for my Dodge 383 stroker EFI conversion. So far, I have a plenum floor :) http://xephic.dynip.com/dodge/dodge.html - --- Frederic Breitwieser Xephic Technology "Leadership in IT" Bridgeport, CT 06606 Web: http://www.xephic.dynip.com Voice: (203) 372-2707 Fax: (603) 372-1147 ------------------------------ Date: Sun, 2 May 1999 16:47:40 -0700 (PDT) From: Jim Davies Subject: Re: Flame - Not (Tornado engine?) On Sun, 2 May 1999, Greg Hermann wrote: > > > >Oh, yeah. Continental has an interesting policy on parts prices. > > All true. The Argentinian Kaiser plant in Cordoba came up with some revised > rods along with the twelve port head. The car you would find such a beast > in was called a "Torino"--but not at all like a Ford by the same name. It > was based on the late sixties Rambler American body tub, but had an outer > skin done by Pinin Farina. It also had IRS, and about 8 inches of wheel > travel at each corner, and a five speed gear box which was built under > license from ZF. > > Note the rather low engine speed for the peak power on the Torino version > of the Tornado engine--this speaks to Jim's comments about the Continental > block, even with far better rods installed. Scary to think how much power > they could have made with a stronger block and crank and some more revs and > 48 mm in place of 45 mm Webers! > Continental also mfrd an inline 6 cylinder, pushrod, 12 port 7 main industrial engine. The only one I ever saw was in a Trackmobile. Delivered new with the governor not working. It never popped, and it wasnt for lack of trying. Could make it sound just like a good, strong SBC going thru the traps...If they had combined short block and cylinder heads... ------------------------------ Date: Sun, 02 May 1999 20:49:00 -0500 From: dave.williams@xxx.us (Dave Williams) Subject: High economy, was Fuel injection plugs - -> Van Dorne has built a CVT for the Williams F1 car that could handle - -> 700 hp. Probably the same CVT. 70hp for 100,000 miles in a Subaru, or 700hp for 100 miles in a Williams. Van Doorne has used several belt-type systems over the years, but they all have sharp limits as to the amount of torque they can handle before the wear rate goes through the roof. Lear pumped a lot of money into 'traction drive' (torus and roller) variants during the 1960s, and even got a few of them installed in buses for testing. They did well, but in order to keep wear under control the elements became huge - the reason they tested them in buses was because they wouldn't *fit* in cars. ==dave.williams@xxx.us====================================== I've got a secret / I've been hiding / under my skin / | Who are you? my heart is human / my blood is boiling / my brain IBM | who, who? =================================== http://home1.gte.net/42/index.htm ------------------------------ Date: Sun, 02 May 1999 21:16:00 -0500 From: dave.williams@xxx.us (Dave Williams) Subject: Re: Transplant - -> Floating rod bearings too? Hell, no! This is a late-model motor - 1953. Uses ordinary snap-in shell bearings. Even has a distributor on a stick instead of the crab distributor driven off the cam snout. ------------------------------ Date: Sun, 2 May 1999 19:57:20 -0700 From: "Greg Moore" Subject: TPS This is a multi-part message in MIME format. - ------=_NextPart_000_004F_01BE94D5.FD2D4560 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hello all, I just stumbled on this list. I've got a question I'm hoping someone can = answer for me. I'm converting a '59 Mercedes Unimog to multiport EFI. I've got a Ford = throttle position sensor (part # E45F-9B989 AA 4M01C) but the lugs seem = to be 90 degrees out of wack. Is there a similar sensor that would work = for me? The air door is a 65 mm Edelbrock/BBK unit intended for a '95 = Mustang V8 if that helps. Thanks everyone. Cheers, Greg "20th century 'mog" '59 Unimog - ------=_NextPart_000_004F_01BE94D5.FD2D4560 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Hello all,
 
I just stumbled on this list. I've got a question = I'm hoping=20 someone can answer for me.
 
I'm converting a '59 Mercedes Unimog to multiport = EFI. I've=20 got a Ford throttle position sensor (part # E45F-9B989 AA 4M01C) but the = lugs=20 seem to be 90 degrees out of wack. Is there a similar sensor that would = work for=20 me? The air door is a 65 mm Edelbrock/BBK unit intended for a '95 = Mustang V8 if=20 that helps.
 
Thanks everyone.
 
Cheers, Greg  "20th century 'mog"
'59 Unimog
- ------=_NextPart_000_004F_01BE94D5.FD2D4560-- ------------------------------ Date: Mon, 03 May 1999 13:06:34 +1000 From: Matthew Harding Subject: Re: valve job question >off the carbon that was on top of the cylinders. I used to rotate the engine >around and bring the pistons up to tdc and whirl away with a drill bit >mounted wire brush. > > >nowadays I wonder if all it did was make the piston top pretty and introduce >lots of debris into the engine especially the cylinder walls, creating years >of wear in minutes. Like you i've been known to do the same thing with the drill bit mounted wire brush whilst the head is off (on my own motors), just filling in time i guess and more than anything making it look shmick for any one who comes by :P when I do I simply make sure that I have someone else holding the compressed air across the top of the piston at the same time, and rags down the adjacent cylinders. generally most of the debris gets blown away, and any that is down the gap can be blown out with the compressed air. When you rotate that piston to the bottom again, just carefully wipe up the bore with a clean rag, that will get any lingering debris. If you are really concerned, just turn the engine over by hand a couple more times, and look for any more being dropped by the piston as it goes down the bore. just my thoughts :) One thing i do think it can help with is a high compression engine pinging, because (for a short time) there is no carbon deposits to stay hot enough to ignite the fuel/air. again just my thoughts, and some observation... cya ------------------------------ Date: Sun, 02 May 1999 23:10:57 -0400 From: Shannen Durphey Subject: Re: Fuel injection plugs Bruce Plecan wrote: > > Your saying you've had the secondary metering rod orfices go bad?. > By how much?.... > Never saw any worn enough that that worried me. > Finding the optimum opending for the secondary air valve was the PITA for > me. > Well right after digging up all the metering rod hangers, and many needles. > Then I built a jig for blueprinting the hangers.. > Once ya got the idle jet, idle channel restrictor right then ya could play > with the primary idle bypasses. Then you just had to diddle with the primary > jets, and dancing needles (ecm content). > Had one on a LG4 auto that ran 15.0s, and got 30+mph on the freeway. > Same metering also ran 13's on a 355 (crossfire manifold sorta) > Grumpy The electronic Q's just aren't that common. I've only worked on a handful of them. I was told by a GM Training Center guy "just throw it out and get a Holley" when I was in college. Wish I'd known ya then, I needed something to come back with. Secondary jets... I've changed the later style to the early ones. The early ones look more like a cup than a stamped orifice. The height is a little different, I was playing around. In the beginning I had some silly notion of using replaceable jets. I've mostly seen the rods wear enough to be a problem, but I've pulled a couple orifices that were worn to an oval in a 1 ton field service truck. Lotsa fuel at WOT, looked like a diesel. Good thing I saved the drill bit. On my own stuff, I try to find a carb without the idle air bushings. These also usually have larger holes for the mixture screws. Try to simplify things a bit. Ever run into a hanger with one arm at a very different height? I've gotten a few, don't know what caused it. Each one was causing a pop from the secondary, got to be the first thing I looked for. 30 mpg, that's great. I thought I was doing well to get 18 from the 455 in the Monte. Neat thing, was 18 with 2.26 rear gear, still 18 with 3.08 gear. Runs out of cam with 3.08 though. I heard about your "carbfire" manifold. I never tried that with mine, didn't know I could remove the extra casting. Still love the crossfire setup, way underrated. Shannen ------------------------------ Date: Sun, 02 May 1999 21:38:00 -0500 From: dave.williams@xxx.us (Dave Williams) Subject: Re: Transplant - Bearings - -> Please explain the term "floating rod bearings"......... I've - -> never heard it before...... The only "floating rod bearings" I've - -> experienced are those which spin between the bearing and the - -> rod.......... Definitely a bad deal.... forshadows doom! Back in the 1930s many engines used bearings that were cast directly onto the rod or block surfaces and machined or scraped to size. The bearing material was an alloy called Babbitt, (there were actually a number of different Babbitt alloys) and the resulting bearings were referred to as "babbitt bearings." Cast babbitt bearings were relatively time-consuming to make, so as labor prices went up they became less cost-effective. It was also found that thinner bearings could hold up to load better than thick bearings. Many engines began using "shell" or "insert" bearings - thin strips of steel with a thin layer of bearing material - Babbitt alloy, lead/silver, etc. - cast or laminated in place. These bearings were normally a tight fit in their housings; in fact, the OD of the bearing was usually slightly *larger* than the housing; the difference is called "crush" and is what keeps the bearing from spinning in the housing. These types of bearings are in common use today. Ford went to an insert bearing on the flathead, but the rod bearings were strange - they were babbitted on both sides, and floated in between the crankshaft and rod. Later they went to conventional interference fit bearings. The hot-rodders of the day claimed there was little difference between the floating and interference bearings. I've found no detailed technical information on why Ford chose to do the floating bearings instead of interference bearings, or why they changed. I suspect it had something to do with cost, as the flathead V8 was rigorously designed down to a price. ==dave.williams@xxx.us====================================== I've got a secret / I've been hiding / under my skin / | Who are you? my heart is human / my blood is boiling / my brain IBM | who, who? =================================== http://home1.gte.net/42/index.htm ------------------------------ Date: Sun, 02 May 1999 22:09:00 -0500 From: dave.williams@xxx.us (Dave Williams) Subject: Espen's Reed Valves - -> cam to get variable duration and the reed valves would take care of - -> the blowback problem at the low end...... At least a first thought Alfa Romeo built some engines like that 20 years ago. There were also some stationary engines using reed valves at the beginning of the century. The Alfa setup let them run a long duration cam without confusing the carburetor with reversion pulses or contaminating one cylinder's intake charge with another's exhaust coming through on overlap. It looked like a fine idea to me, and I have no idea why they dropped it. ------------------------------ Date: Sun, 02 May 1999 22:20:00 -0500 From: dave.williams@xxx.us (Dave Williams) Subject: Re: Flame - Not - -> cyl also. Then there's the 348/409 Chebby which has valves in head - -> but no combustion cchamber cast in. Just like the 430/462 Ford, or the Mercedes 300, or... ------------------------------ Date: Sun, 02 May 1999 22:28:00 -0500 From: dave.williams@xxx.us (Dave Williams) Subject: Re: atomization enhancement - -> There has been some recent research that indicates the best - -> atomization occurs when the exhaust hits the puddled fuel behind the - -> intake valve when the valve opens. 1) you're talking about a pretty small amount of fuel here, which is supposed to be in vaporized or fine droplet form anyway 2) that valve is hopping up and down pretty-damned-quick, even at idle. Not much chance for puddling there. 3) there's one hell of a lot of turbulence in that intake port, both from the valve's movement on and off the seat and from charge reversion during overlap, not to mention turbulence from the other cylinders on a common manifold. On an alcohol-burning Chevy in a sprint car, bogged down coming out of a corner, I could believe in fuel puddling on the back of the intake valve. In almost anything else, it's "show me" time. ==dave.williams@xxx.us====================================== I've got a secret / I've been hiding / under my skin / | Who are you? my heart is human / my blood is boiling / my brain IBM | who, who? =================================== http://home1.gte.net/42/index.htm ------------------------------ Date: Sun, 02 May 1999 22:31:00 -0500 From: dave.williams@xxx.us (Dave Williams) Subject: Re: Direct Injection - Stratified - -> Any time a device that restricts flow is introduced into the path of - -> air and fuel, power is reduced. A pre-chamber is such a device and - -> such an engine will lose efficiency compared to an open chamber - -> design. A prechamber doesn't necessarily have to restrict flow. It can be *in addition* to normal flow, as was used in various Japanese automobile engines a few years ago. ==dave.williams@xxx.us====================================== I've got a secret / I've been hiding / under my skin / | Who are you? my heart is human / my blood is boiling / my brain IBM | who, who? =================================== http://home1.gte.net/42/index.htm ------------------------------ Date: Tue, 4 May 1999 22:03:17 -0700 From: "Howard Wilkinson" Subject: Re: Fuel injection plugs Bruce: The "spreadbore" (I believe that's the term) design of the Quadrajet results in the secondarys contributing to normal driving far more than on carbs with equal primarys & secondaries. As a result a little bit of wear in these rods or orfices makes a big difference in performance. I could show you quite a number of Quadrajet carbs with visibly egged out secondary orfices.... These are 100k+ carbs, and I just throw them away and find a good one. Unfortunately I've found that the factory "rebuilts" often have this same problem. Perhaps as I deal more in pickups and trucks than in cars, the is some difference in the operating environment which accounts for the problem...... Who knows. I just know that if I have one that doesn't work, it nearly always turns out to have egged secondary jets. H.W. - -----Original Message----- From: Bruce Plecan To: diy_efi@xxx.edu Date: Sunday, May 02, 1999 7:28 PM Subject: Re: Fuel injection plugs > >Your saying you've had the secondary metering rod orfices go bad?. >By how much?.... >Never saw any worn enough that that worried me. >Finding the optimum opending for the secondary air valve was the PITA for >me. >Well right after digging up all the metering rod hangers, and many needles. >Then I built a jig for blueprinting the hangers.. >Once ya got the idle jet, idle channel restrictor right then ya could play >with the primary idle bypasses. Then you just had to diddle with the primary >jets, and dancing needles (ecm content). > Had one on a LG4 auto that ran 15.0s, and got 30+mph on the freeway. >Same metering also ran 13's on a 355 (crossfire manifold sorta) >Grumpy > > >> > Quadrajet would have had the most potential of any of them if they had >> > only made replaceable secondary orfices.... once these are worn >> > there's nothing to be done. >> Around 1985 a company called "The Carburetor Shop" offered a kit >> designed to replace the secondary metering jets. Generally I see worn >> rods, not jets. Most common seems to be a "ring" worn around the rod >> caused by the rods "rattling" in the stainless plates that make up the >> jets. >> > I've built a puller and removed them, and >> Puller? I have a drill bit that I've ground to cut the aluminum carb >> away from the jet, then a small pick easily pulls the exposed jet. >> > I suppose you could manufacture a replacement, >> I pull the replacement jet from an unused Q jet. I buy the carbs >> cheap and strip them for parts. >> Shannen > > > ------------------------------ Date: Sun, 2 May 1999 22:05:45 -0700 (PDT) From: Jim Davies Subject: Re: Transplant - Bearings On Sun, 2 May 1999, Dave Williams wrote: > > -> Please explain the term "floating rod bearings"......... I've > -> never heard it before...... The only "floating rod bearings" I've > -> experienced are those which spin between the bearing and the > -> rod.......... Definitely a bad deal.... forshadows doom! > > Ford went to an insert bearing on the flathead, but the rod bearings > were strange - they were babbitted on both sides, and floated in between > the crankshaft and rod. Later they went to conventional interference > fit bearings. The hot-rodders of the day claimed there was little > difference between the floating and interference bearings. I've found > no detailed technical information on why Ford chose to do the floating > bearings instead of interference bearings, or why they changed. I > suspect it had something to do with cost, as the flathead V8 was > rigorously designed down to a price. > I have run across a set of used boxed rods for a 354 Chrysler hemi that were modified to use floating rod bearings. These were used in a fueler. Ford also used this style of rod bearing in the GAA and GAF V8 tank engines. Whether they were also used in the original V-12 A/C engine I don't know. Maybe this is like the offset versus fork-and-blade con rod designs, where costs seemed to dictate the winner but there does not seem to be any documentation on tests etc. ------------------------------ Date: Sun, 02 May 1999 23:18:06 -0700 From: Ross Corrigan Subject: Re: NC hybrid setup/coolant blows heater core/how to avoid? At 06:56 PM 5/2/99 -0400, you wrote: >Ross Corrigan wrote: > >> thanks again for all this feedback, I"m going to gather them up as a FAQ to >> post on my page eventually for us ZV8's. >> >> FWIW, their Datsun heater cores were 20+ yrs old and functioning fine when >> they first went, no quality problems their. Shannen wrote: >Ross, what kind of car is this? Mine's a 280ZX, theirs were a 240Z and a 280ZX. I ran SB Chevy (several, actually) in >a 240Z and never experienced a problem. WOT dustoff?? When do you >need WOT?? ; ) hard to tag 10's or 11's w/o WOT they found;^) I only need it long enough to prove to the passenger they can't grab that C note taped to the dash;^) Funny you say that, a camaro guy was talking about testing a certain tranny in 4th or similar at WOT and the datsun V8 guy said he couldn't stay at WOT long enought to test much of anything 'cept his nerves;^) {wide open throttle till you see God and then lift} Ross (dreaming again ) C Any pics or writeups of your Z8's?? I'm starting a collection of web info to supplement a friends webpage http://www.whit.org:80/jcaudle/ I always enjoy reading and viewing others rides to see what they've done etc, better than any car mags IMO;^) Ross Corrigan / Vancouver, Canada '80 327ZX IZCC#255, Edmonton Z-car Club #44, British Columbia ZCR Life's a journey, not a destination.. Enjoy the pitstops and maximize the straights mailto:zxv@xxx.ca *New ICQ # 11549358 http://home.iSTAR.ca/~zxv/index.shtml http://207.212.212.139/~corrigan/gearheads/pics/wheels/sirbg.jpg where a Z belongs ------------------------------ Date: Mon, 03 May 1999 06:21:07 GMT From: bob@xxx.com (Robert Harris) Subject: Re: atomization enhancement Its not. The back side of the intake valve under medium load can exceed 600F ( Vizard ) and this is one of the reasons that simply ceramic coating the face of the intake can drop the charge temperature 60 degrees or more. It has long been used in constant flow systems like the hilborn to greatly aid accelerations. The hot valve simply transfers its heat to the fuel. Member that the intake valve has just been exposed to 360 degrees of intense heat during combustion and exhaust by simply being in the chamber. Date: Sun, 02 May 1999 12:21:01 -0400 From: "David A. Cooley" Subject: Re: atomization enhancement At 10:10 AM 5/2/99 -0400, you wrote: >There has been some recent research that indicates the best atomization >occurs when the exhaust hits the puddled fuel behind the intake valve when >the valve opens. Atomization of fuel as it leaves the injector is not >terribly important. Yes, but that's not atomization, that's vaporization... and if it's caused by the exhaust hitting the puddled fuel, that means it's being blown back into the intake runner causing intake dilution and fuel distribution problems. =========================================================== David Cooley N5XMT Internet: N5XMT@xxx.net Packet: N5XMT@xxx. Member #7068 Sponges grow in the ocean... Wonder how deep it would be if they didn't?! =========================================================== - ------------------------------ ------------------------------ End of DIY_EFI Digest V4 #259 ***************************** 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".