Re: [MBZ] Four barrel enthusiast
Not actually a rich mixture, rather the charge density is so low it won't burn properly -- high CO and high unburned hydrocarbons from the very high manifold vacuum (and hence very low combustion chamber pressure -- usually below atmospheric). The slow close throttle prevents some of the pollution. On the KE-Jet, the fuel is shut off instead, which works better -- you get proper closed throttle deceleration. Peter
Re: [MBZ] Four barrel enthusiast
No, that's for CO control on decel, I think -- certainly it was true on the 75 Audi that had plain K-Jet. KE-Jet won't have the problem since the mixture is controlled closer. Peter
Re: [MBZ] Four barrel enthusiast
Peter Frederick wrote: No, that's for CO control on decel, I think -- certainly it was true on the 75 Audi that had plain K-Jet. I'm thinking we might be saying the same thing in different ways. Wouldn't an excessively rich mixture cause high CO? I'm slowly expanding my knowledge of CIS since buying an '89 VW Cabriolet. :) I had some passing contact with it before, and I like it, but now I'm really digging in to troubleshooting some erratic idle issues.
Re: [MBZ] Four barrel enthusiast
Yup, D-Jet. K-Jet DOES have a very short lag due to the need to pull the flap open, but I've never had any problems with that. If that bothers you, DON'T get a diesel! You have to use more pedal to get moving yet! LH-Jet and similar systems respond faster, but the lurch forward at full throttle' effect is, I think, determined by the linkage -- never present in a Benz, snaps your neck back in a GM, and it's certainly not a result of actual power -- I suspect there is also some effect from having the engine designed for max torque at 1500 rpm or less (GM and other setups with high ratio overdrive trannies where the engine is turning 1200 rpm at 70 mph) and the Benz style were the engine will be running 3500 rpm at 70. I mentioned this to a friend who runs a body and muffler shop -- he had the same comment. Much nicer to drive the Benz at low speed as it's much more controlable. Peter
Re: [MBZ] Four barrel enthusiast
Peter Frederick wrote: K-Jet DOES have a very short lag due to the need to pull the flap open, but I've never had any problems with that. Is the inverse of that effect why some K-Jet cars have a device to prevent the throttle plate from snapping closed suddenly when you lift off the accelerator? I imagine the throttle snapping closed and the metering flap taking longer to return, causing a momentary rich mixture.
Re: [MBZ] Four barrel enthusiast
Well it is possible to get pretty close without a CO meter but the problem is people try to compensate for other problems by screwing with the metering adjustment. Adjusting the metering screw should be last thing to be done, after everything else is checked out. One of the most important factors is fuel quality, no good trying to get a MB motor to run well on crap fuel. If the metering adjustment is to be fiddled with make sure that the hole where the Allen key goes is clean and that the Allen key is a good fit (a good quality T handle Allen key is the go for this job), also if I remember right the adjusting screw has to be pushed down to engage the actual adjuster (hence the T handle). Hendrik who has turned the metering adjustment with some success - Original Message - From: David Brodbeck [EMAIL PROTECTED] To: Mercedes Discussion List [EMAIL PROTECTED] Sent: Saturday, February 11, 2006 11:55 AM Subject: Re: [MBZ] Four barrel enthusiast I like it too, although people seem to treat it like it's some sort of deep, dark magic. It's basically a carburator, but spread out all over the engine. ;) It really is quite an ingenious system once you figure it out. Reliable, too; my experience is that most CIS problems could have been avoided if each car had come with a trained monkey that would slap the owner silly if they went near the fuel distributor with an allen wrench. People didn't quite get that you couldn't just tweak it by ear like a carb to try to make it run better.
Re: [MBZ] Four barrel enthusiast
LH-jet is a later derivative of D-Jet -- uses a hall effect pickup for injection timing and fires individual injectors instead of pairs, and has a mass flow sensor rather than a pressure sensor. The actual delivery guts were pretty much the same up to about 1993. Benz started using it in 93 or 94 when the Feds required meter each cylinder cycle) nonsense. Went fully digital in the late 90s. It's been around since the early 80s, I think -- Volvo used it on their four cylinders to replace D-Jet. Peter
Re: [MBZ] Four barrel enthusiast
Agreed, CIS is better, just not that much smarter, i.e. it doesn't analyze variables, then meter accordingly. Other than the cold start circuit, it doesn't do much other than meter according to airflow in the intake--much like a carburetor. I like CIS, sort of. On 2/10/06, Peter Frederick [EMAIL PROTECTED] wrote: I beg to differ -- K-Jet is MUCH better at fuel metering than a carb -- the variation in mixture as throttle varies is much less. The fact that the injectors are placed for maximum dispersion and no intake with fuel/air mix running through it make all the difference in the world. No need for an acceleration pump, for instance, should tell you a lot. CIS is much simpler than a carb, except for actual manufacture. - Casey Olympia, WA Biodiesel: I drive in a persistent vegetative state '87 300TD intercooler (211k) '84 300D (210k) Gashuffer: '89 Vanagon Wolfsburg Edition (187K)
Re: [MBZ] Four barrel enthusiast
Certain Porsches and VW type 2 vehicles used L-jet, or AFC injection. I think it might have been the last analog-based electrical injection Bosch produced. Fairly robust, but the airflow meters were prone to failure if the engine ever backfired. On 2/10/06, Kaleb C. Striplin [EMAIL PROTECTED] wrote: what uses L-jet? Not familiar with that. Casey Olympia, WA Biodiesel: I drive in a persistent vegetative state '87 300TD intercooler (211k) '84 300D (210k) Gashuffer: '89 Vanagon Wolfsburg Edition (187K)
Re: [MBZ] Four barrel enthusiast
Zeitgeist wrote: Agreed, CIS is better, just not that much smarter, i.e. it doesn't analyze variables, then meter accordingly. Other than the cold start circuit, it doesn't do much other than meter according to airflow in the intake--much like a carburetor. I like CIS, sort of. I like it too, although people seem to treat it like it's some sort of deep, dark magic. It's basically a carburator, but spread out all over the engine. ;) It really is quite an ingenious system once you figure it out. Reliable, too; my experience is that most CIS problems could have been avoided if each car had come with a trained monkey that would slap the owner silly if they went near the fuel distributor with an allen wrench. People didn't quite get that you couldn't just tweak it by ear like a carb to try to make it run better. L-Jetronic is somewhat more persnickety, though not really much more complex. LH-Jetronic, with the hot-wire airflow sensor, seems to be more reliable than the older version with the mechanical one. D-Jet and early L-Jet both suffered from a lack of limp-home modes -- any one sensor or wiring failure could leave you stranded.
Re: [MBZ] Four barrel enthusiast
Peter Frederick wrote: LH-jet is a later derivative of D-Jet -- uses a hall effect pickup for injection timing and fires individual injectors instead of pairs, and has a mass flow sensor rather than a pressure sensor. The actual delivery guts were pretty much the same up to about 1993. Benz started using it in 93 or 94 when the Feds required meter each cylinder cycle) nonsense. Went fully digital in the late 90s. It's been around since the early 80s, I think -- Volvo used it on their four cylinders to replace D-Jet. AFAIK LH-Jetronic was still batch fire, like D-Jetronic -- at least the 1980s revisions of it. I have little knowledge of what happened with it after 1989. L-Jetronic was made by Bosch and used on *many* vehicles. It was used on VW Buses starting in 1975, and VW used variations of it (called Digijet and Digifant) into the '90s. LH-Jetronic used a hotwire mass airflow sensor instead of a mechanical one, and was used by Volvo on their 4-cylinder cars for at least a decade starting in the early '80s. The mechanical parts -- injectors, etc. -- stayed pretty similar over the years. Differences included the addition of an oxygen sensor; the addition of, and revisions to, an idle speed control motor; and improvements to the ECU to allow limp-home and eventually self-diagnostics. (L-Jetronic originally had none of these; open up an early L-Jet CPU and you'll find op-amps and transistors, but nothing digital!) The primary difference between L-Jet and D-Jet was that D-Jet used manifold pressure as its main reference, and L-Jet used a mass airflow sensor.
Re: [MBZ] Four barrel enthusiast
It was never as popular as K-jet due to reliability and complexity, Swedish bricks used the K-jet as well in some of their vehicles. Hendrik - Original Message - From: Peter Frederick [EMAIL PROTECTED] To: Mercedes Discussion List [EMAIL PROTECTED] Sent: Saturday, February 11, 2006 10:26 AM Subject: Re: [MBZ] Four barrel enthusiast LH-jet is a later derivative of D-Jet -- uses a hall effect pickup for injection timing and fires individual injectors instead of pairs, and has a mass flow sensor rather than a pressure sensor. The actual delivery guts were pretty much the same up to about 1993. Benz started using it in 93 or 94 when the Feds required meter each cylinder cycle) nonsense. Went fully digital in the late 90s. It's been around since the early 80s, I think -- Volvo used it on their four cylinders to replace D-Jet. Peter ___ http://www.striplin.net For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://striplin.net/mailman/listinfo/mercedes_striplin.net -- No virus found in this incoming message. Checked by AVG Anti-Virus. Version: 7.0.338 / Virus Database: 267.15.2/253 - Release Date: 7/02/2006
Re: [MBZ] Four barrel enthusiast
I am not able to find that SLC listing from CL anymore, but the fellow called and has dropped price to $3k instead of $4500. Nice blue car, euro lights with heated seats. Anybody interested, I will dig further. On Friday, February 10, 2006, at 09:18 AM, andrew strasfogel wrote: Yeah, and my CIS 450 SLC got 12-15 mpg tops! On 2/9/06, OK Don [EMAIL PROTECTED] wrote: One would think so, but why did I get in the 20's mpg in the 283 (4640cc) '58 chevy with a four barrel, and only 15 mpg in the CIS 450SLC (275ci)? Emission controls? Yes - the type III 2.0L VW bus I had was far more reliable than the 1.2L with the single Solex even. I did love to tune 2 and 3 carb SU setups though -- had the touch back then --- On 2/9/06, Peter Frederick [EMAIL PROTECTED] wrote: CIS injection (more effective mixture control than D-Jet) is good for at least 10% more hp and 15% better fuel milage on the same engine as a carb. Unless you have a fairly esoteric manifold system (hard to put under a hood), carbs provide pretty poor atomization, and suffer badly from lousy fuel distribution at low throttle openings. Even D-jet turned the type 11 and type III VWs into very reliable, efficient cars from cranky trouble causers -- it was almost impossible to keep the twin carbs balanced on that flat four. Peter -- OK Don, KD5NRO Norman, OK '90 300D 243K, Rattled '87 300SDL 290K, Limo Lite, or blue car '81 240D 173K, Gramps, or yellow car '78 450SLC 67K, brown car '97 Ply Grand Voyager 78K Van Go ___ http://www.striplin.net For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://striplin.net/mailman/listinfo/mercedes_striplin.net ___ http://www.striplin.net For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://striplin.net/mailman/listinfo/mercedes_striplin.net -- Clay Seattle Bioburner 1972 220D - Gump 1995 E300D - Cleo 1987 300SDL - POS - DOA The FSM would drive a Diesel Benz
Re: [MBZ] Four barrel enthusiast
Hendrik Riessen wrote: It was never as popular as K-jet due to reliability and complexity, Swedish bricks used the K-jet as well in some of their vehicles. In particular, Volvo 240 Turbos were K-Jet.
Re: [MBZ] Four barrel enthusiast
No need for an acceleration pump, for instance, should tell you a lot. I've always blamed our SLs' lack of instant acceleration (What, ME? response to a throttle stab) on the lack of an accelerator pump mechanism. (They are the only gasser FI cars we own. The rest are carbs or diesels. All three are CIS variants. A crapload of cars in the driveway, and not a FWD, 4-cyl gasser, or V-anything-but-8 in the bunch. We are _not_ average. But I digress...) Cars I've driven (in the remote misty past) that had pump problems all had a serious stumble, though, much worse than CIS's lethargic response. -- Jim
Re: [MBZ] Four barrel enthusiast
740 turbos were LH-Jet though -- I know, I fixed my sisters. Peter
Re: [MBZ] Four barrel enthusiast
Yeah, I've heard from several sources about the lack of throttle response of MB EFI systems. Not true on the 280 SE 4.5 -- that one dumps out black smoke from extra fuel (you also get 10% enrichment at full throttle, not an inducment to thrifty driving). I think it's much more a matter of how the geometry of the accelerator works than real throttle lag -- Japo cars (and GM) and set up to snap the throttle about 2/3 open with 1/4 movement of the pedal, Benz is much more linear. The result is that you HAVE to floor the pedal to get full power, unlike that miserable Mitsubishi I drove as a rental car -- hard to drive, I was having to lift my foot and eggshell all the time. Peter
Re: [MBZ] Four barrel enthusiast
Yeah, I've heard from several sources about the lack of throttle response of MB EFI systems. Not true on the 280 SE 4.5 -- that one dumps out black smoke from extra fuel (you also get 10% enrichment at full throttle, not an inducment to thrifty driving). That's the D-Jet system, right? I think it's much more a matter of how the geometry of the accelerator works than real throttle lag -- Japo cars (and GM) and set up to snap the throttle about 2/3 open with 1/4 movement of the pedal, Benz is I can't describe how much I loathe this behavior. When we had to leave our SDL in Vancouver and rent a GM Herzmobile to go down to Seattle to pick up the cruise ship the bitching just about never stopped, or so says my wife. Those cheap lying GM bas**rds rig it that way so it seems like the car has a lot of power. Yeah, if you're ten years old. Car feels like it's driven by toggle switch. Throttle? We got both kinds: on _and_ off! much more linear. The result is that you HAVE to floor the pedal to get full power, unlike that miserable Mitsubishi I drove as a rental car -- hard to drive, I was having to lift my foot and eggshell all the time. I do, often. But there is a notable difference in initial jump (and I don't just mean from dead stop) between my 84 carbureted Camaro and our three CIS SL's, both 450 and 560. Now, once a 560 _does_ come on it's just fine. -- Jim
Re: [MBZ] Four barrel enthusiast
On Friday, February 10, 2006, at 08:42 PM, Hendrik Riessen wrote: It was never as popular as K-jet due to reliability and complexity, Swedish bricks used the K-jet as well in some of their vehicles. As did Porsche and Datsun/Nissan IIRC. Johnny B. I Mac Therefore I am
Re: [MBZ] Four barrel enthusiast
John Berryman wrote: On Friday, February 10, 2006, at 08:42 PM, Hendrik Riessen wrote: It was never as popular as K-jet due to reliability and complexity, Swedish bricks used the K-jet as well in some of their vehicles. As did Porsche and Datsun/Nissan IIRC. Also DeLorean, I think!
Re: [MBZ] Four barrel enthusiast
No, that's exactly my point! Those crazy Europeans with their weird little fuel-injected engines at the wrong end of the car! A carbureted V-8 ought to have been good enough for anyone in 1968. Spoken like a a true Pontiac Bonneville owner. Also, 1968 was the first year for emission control, at least in the German cars. RLE
Re: [MBZ] Four barrel enthusiast
CIS injection (more effective mixture control than D-Jet) is good for at least 10% more hp and 15% better fuel milage on the same engine as a carb. Unless you have a fairly esoteric manifold system (hard to put under a hood), carbs provide pretty poor atomization, and suffer badly from lousy fuel distribution at low throttle openings. Even D-jet turned the type 11 and type III VWs into very reliable, efficient cars from cranky trouble causers -- it was almost impossible to keep the twin carbs balanced on that flat four. Peter
Re: [MBZ] Four barrel enthusiast
One would think so, but why did I get in the 20's mpg in the 283 (4640cc) '58 chevy with a four barrel, and only 15 mpg in the CIS 450SLC (275ci)? Emission controls? Yes - the type III 2.0L VW bus I had was far more reliable than the 1.2L with the single Solex even. I did love to tune 2 and 3 carb SU setups though -- had the touch back then --- On 2/9/06, Peter Frederick [EMAIL PROTECTED] wrote: CIS injection (more effective mixture control than D-Jet) is good for at least 10% more hp and 15% better fuel milage on the same engine as a carb. Unless you have a fairly esoteric manifold system (hard to put under a hood), carbs provide pretty poor atomization, and suffer badly from lousy fuel distribution at low throttle openings. Even D-jet turned the type 11 and type III VWs into very reliable, efficient cars from cranky trouble causers -- it was almost impossible to keep the twin carbs balanced on that flat four. Peter -- OK Don, KD5NRO Norman, OK '90 300D 243K, Rattled '87 300SDL 290K, Limo Lite, or blue car '81 240D 173K, Gramps, or yellow car '78 450SLC 67K, brown car '97 Ply Grand Voyager 78K Van Go
Re: [MBZ] Four barrel enthusiast
Yeah, and my CIS 450 SLC got 12-15 mpg tops! On 2/9/06, OK Don [EMAIL PROTECTED] wrote: One would think so, but why did I get in the 20's mpg in the 283 (4640cc) '58 chevy with a four barrel, and only 15 mpg in the CIS 450SLC (275ci)? Emission controls? Yes - the type III 2.0L VW bus I had was far more reliable than the 1.2L with the single Solex even. I did love to tune 2 and 3 carb SU setups though -- had the touch back then --- On 2/9/06, Peter Frederick [EMAIL PROTECTED] wrote: CIS injection (more effective mixture control than D-Jet) is good for at least 10% more hp and 15% better fuel milage on the same engine as a carb. Unless you have a fairly esoteric manifold system (hard to put under a hood), carbs provide pretty poor atomization, and suffer badly from lousy fuel distribution at low throttle openings. Even D-jet turned the type 11 and type III VWs into very reliable, efficient cars from cranky trouble causers -- it was almost impossible to keep the twin carbs balanced on that flat four. Peter -- OK Don, KD5NRO Norman, OK '90 300D 243K, Rattled '87 300SDL 290K, Limo Lite, or blue car '81 240D 173K, Gramps, or yellow car '78 450SLC 67K, brown car '97 Ply Grand Voyager 78K Van Go ___ http://www.striplin.net For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://striplin.net/mailman/listinfo/mercedes_striplin.net
Re: [MBZ] Four barrel enthusiast
Peter Frederick wrote: CIS injection (more effective mixture control than D-Jet) is good for at least 10% more hp and 15% better fuel milage on the same engine as a carb. Unless you have a fairly esoteric manifold system (hard to put under a hood), carbs provide pretty poor atomization, and suffer badly from lousy fuel distribution at low throttle openings. Even D-jet turned the type 11 and type III VWs into very reliable, efficient cars from cranky trouble causers -- it was almost impossible to keep the twin carbs balanced on that flat four. My personal experience with open-loop fuel injection (systems without a lambda sensor, like early CIS, D-Jet, and early L-Jet) is that it runs better than a carb, but gives about the same fuel economy. Once you add a lambda sensor the fuel economy benefits start to show up.
Re: [MBZ] Four barrel enthusiast
CIS isn't a whole lot smarter than a carburetor, but it is simple and relatively easy to diagnose. D-jet is a cruel joke, but I actually like L-jet for its simplicity. On 2/10/06, David Brodbeck [EMAIL PROTECTED] wrote: My personal experience with open-loop fuel injection (systems without a lambda sensor, like early CIS, D-Jet, and early L-Jet) is that it runs better than a carb, but gives about the same fuel economy. Once you add a lambda sensor the fuel economy benefits start to show up. Casey Olympia, WA Biodiesel: I drive in a persistent vegetative state '87 300TD intercooler (211k) '84 300D (210k) Gashuffer: '89 Vanagon Wolfsburg Edition (186K)
Re: [MBZ] Four barrel enthusiast
Yeah, and my CIS 450 SLC got 12-15 mpg tops! I think our SL has hit 17 a time or two, but 14-15 is normal IIRC. -- Jim
Re: [MBZ] Four barrel enthusiast
Easy: 2.76 rear end gears in the 58 chevy and 3.55 rear end gears in the Benz. The Chevy also produces somewhat less hp and torque. Emission controls on the later (post 74) SLC also cause serious fuel milage penalties. Peter
Re: [MBZ] Four barrel enthusiast
I beg to differ -- K-Jet is MUCH better at fuel metering than a carb -- the variation in mixture as throttle varies is much less. The fact that the injectors are placed for maximum dispersion and no intake with fuel/air mix running through it make all the difference in the world. No need for an acceleration pump, for instance, should tell you a lot. CIS is much simpler than a carb, except for actual manufacture. Peter
Re: [MBZ] Four barrel enthusiast
what uses L-jet? Not familiar with that. Zeitgeist wrote: CIS isn't a whole lot smarter than a carburetor, but it is simple and relatively easy to diagnose. D-jet is a cruel joke, but I actually like L-jet for its simplicity. On 2/10/06, David Brodbeck [EMAIL PROTECTED] wrote: My personal experience with open-loop fuel injection (systems without a lambda sensor, like early CIS, D-Jet, and early L-Jet) is that it runs better than a carb, but gives about the same fuel economy. Once you add a lambda sensor the fuel economy benefits start to show up. Casey Olympia, WA Biodiesel: I drive in a persistent vegetative state '87 300TD intercooler (211k) '84 300D (210k) Gashuffer: '89 Vanagon Wolfsburg Edition (186K) ___ http://www.striplin.net For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://striplin.net/mailman/listinfo/mercedes_striplin.net -- Kaleb C. Striplin/Claremore, OK 89 560SEL, 87 300SDL, 85 380SE, 85 300D, 84 250 LWB, 83 300TD, 81 300TD, 81 240D, 81 240D, 76 450SEL, 76 240D, 76 300D, 74 240D, 69 250 http://www.striplin.net
