fordmantpw Posted August 30, 2012 Share Posted August 30, 2012 You missed my point....take the short-block assembly and instead of the complexity of the the reverse flow heads and twin mounted turbos in the "V" valley, a pair of "conventional flow" heads and no turbos, just a naturally aspirated version with the injector setup and computer mapping program to match. I think this would be a great medium duty fleet option that would cut approximately 4-6K from the price of the option and give Ford an edge in spreading out development costs to a wider base....and since it has the SAE bellhousing design, it could be made available to third party builders at a significant cost advantage compared to Navistar, Cummins, and VM Motori.....No turbos means less complexity and less cost. I believe this set up would be good for 600 Ft Lbs of torque without breaking a sweat and have a service life of 300K or more..... Again, call it Eco-Stroke....and call it a day..... I thought the reverse flow head was actually simpler? I could be wrong, but thought I read something saying that it was actually a simpler design in the end. Maybe it was just for turbo plumbing, which would be moot in your scenario. However, you won't cut the price of the option by 4-6k by removing the turbo and making the engine completely different from the other engines out there. I would guess dropping the turbo may save a grand or so, but the changes necessary to make the engine different than the others reduces economies of scale. Not to mention, the differences would need to be drastic to make an engine designed from the ground up to rely on a turbo to be acceptable in a heavy duty application in N/A form. And I seriously doubt you could pull 600 ft-lbs from the PS in N/A trim. I'm guessing the turbo adds MUCH more torque than that. I can tell you, my '08 has a bit of turbo lag, and it's a dog in that split-second before the turbos spool up. But once the turbos "kick in", you better be ready because you'll be doing unintentional donuts in the highway! Quote Link to comment Share on other sites More sharing options...
SoonerLS Posted August 30, 2012 Share Posted August 30, 2012 And I seriously doubt you could pull 600 ft-lbs from the PS in N/A trim. I'm guessing the turbo adds MUCH more torque than that. I can tell you, my '08 has a bit of turbo lag, and it's a dog in that split-second before the turbos spool up. But once the turbos "kick in", you better be ready because you'll be doing unintentional donuts in the highway! I don't know--the Coyote 5.0 makes over 400ft-lbs of torque; it's not hard to believe that a well-tuned modern oil-burner of larger displacement could come close to 600ft-lbs. Your PSD may be a dog before the turbo spools, but it's also tuned for the turbo, so I'm not sure that's necessarily a valid comparison. Quote Link to comment Share on other sites More sharing options...
7Mary3 Posted August 30, 2012 Author Share Posted August 30, 2012 (edited) You missed my point....take the short-block assembly and instead of the complexity of the the reverse flow heads and twin mounted turbos in the "V" valley, a pair of "conventional flow" heads and no turbos, just a naturally aspirated version with the injector setup and computer mapping program to match. I think this would be a great medium duty fleet option that would cut approximately 4-6K from the price of the option and give Ford an edge in spreading out development costs to a wider base....and since it has the SAE bellhousing design, it could be made available to third party builders at a significant cost advantage compared to Navistar, Cummins, and VM Motori.....No turbos means less complexity and less cost. I believe this set up would be good for 600 Ft Lbs of torque without breaking a sweat and have a service life of 300K or more..... Again, call it Eco-Stroke....and call it a day..... I see your point, but I think it would be very hard to get that kind of output from a N/A 6.7L, and if you did there would likely be emissions issues. No question though, the engine would be easier to service without the reverse-flow heads, turbo and intercooler. BTW- Bob, have you ever seen a B Mack with the Magnadyne flathead 6? Now there's a beast! Edited August 30, 2012 by 7Mary3 Quote Link to comment Share on other sites More sharing options...
LSchicago Posted August 30, 2012 Share Posted August 30, 2012 I see your point, but I think it would be very hard to get that kind of output from a N/A 6.7L, and if you did there would likely be emissions issues. No question though, the engine would be easier to service without the reverse-flow heads, turbo and intercooler. True, considering the turbo 6.7 in the 450/550 only has 660TQ now. Quote Link to comment Share on other sites More sharing options...
lfeg Posted August 30, 2012 Share Posted August 30, 2012 Torque ratings for commercial duty engines are determined differently than car and light truck engines. For cars and light trucks torques and hp are closer to peak values. For commercial duty the numbers are lower because the engine must run reliably at the rated numbers for extended periods. And removing the turbocharger system from the 6.7 would have a big impact on emmissions, primarily HC and particulates. And the engineering and certifiacation costs would be spread over a relatively small quantity, so esentially no savings. In class 6 and 7, turbocharged diesels have been the norm for over 25 years, and I do not think many fleet managers would want to go back to the days of the 8.2 and 3208. And a V-block engine will never be as easy to service as a straight block, turbo or no. Quote Link to comment Share on other sites More sharing options...
theoldwizard Posted August 30, 2012 Share Posted August 30, 2012 I have said this before ... Fleet operators, who probably buy most of the medium duties, want spark ignited CNG. The initial cost is not much more than a diesel, but there are huge savings in maintenance and operating cost. Unfortunately, NO ONE, is currently making a gas engine with enough torque ! Quote Link to comment Share on other sites More sharing options...
lfeg Posted August 30, 2012 Share Posted August 30, 2012 True. But I do not see anyone who has an existing engine that fits the bill other than the Cummins Westport engines. And they are a diesel design, so there is alot of weight in them. But they just about match the numbers of their diesel brethern. Other than those in 9, 12 and 15 liter sizes, no engine builder is there. And I do not think that anyone is talking about a clean sheet design of a dedicated natural gas engine, at least from looking at published SAE papers. Quote Link to comment Share on other sites More sharing options...
Bob Rosadini Posted August 30, 2012 Share Posted August 30, 2012 True. But I do not see anyone who has an existing engine that fits the bill other than the Cummins Westport engines. And they are a diesel design, so there is alot of weight in them. But they just about match the numbers of their diesel brethern. Other than those in 9, 12 and 15 liter sizes, no engine builder is there. And I do not think that anyone is talking about a clean sheet design of a dedicated natural gas engine, at least from looking at published SAE papers. Wwhat is the weight penalty of say any Cummins (be it ISM, ISX etc) diesel vs. CNG? And these CNG options are very pricey, if you are a weight conscious operator, that too has to be a key factor-cost up front plus a payload penalty. Once again I do believe there are govt' subsidies attempting to push this option. Quote Link to comment Share on other sites More sharing options...
7Mary3 Posted August 30, 2012 Author Share Posted August 30, 2012 I have said this before ... Fleet operators, who probably buy most of the medium duties, want spark ignited CNG. The initial cost is not much more than a diesel, but there are huge savings in maintenance and operating cost. Unfortunately, NO ONE, is currently making a gas engine with enough torque ! I agree. And the initial cost difference is becoming quite close. But, you know what I personally think is stupid? Converting a diesel engine platform to run on CNG/LNG. It makes no sense to use a block and reciprocating assemply that it strong enouigh for compression-ignition in a spark ignition engine. All that extra mass serves no purpose whatsoever. Using something similar to the old gasoline big blocks could result in an engine that has all the power, economy, and reliability at much less size and weight. Quote Link to comment Share on other sites More sharing options...
Bob Rosadini Posted August 31, 2012 Share Posted August 31, 2012 I see your point, but I think it would be very hard to get that kind of output from a N/A 6.7L, and if you did there would likely be emissions issues. No question though, the engine would be easier to service without the reverse-flow heads, turbo and intercooler. BTW- Bob, have you ever seen a B Mack with the Magnadyne flathead 6? Now there's a beast! 7M-Actually some of my fellow club members-older than I would you believe-say the old flatheads could not hold a candle to the V-8 Fords, Internationals etc. The 707 was the big gas job but that was an OHV. I may be wrong butg I think the biggest Magnadyne was a 401. Quote Link to comment Share on other sites More sharing options...
lfeg Posted August 31, 2012 Share Posted August 31, 2012 I agree. And the initial cost difference is becoming quite close. But, you know what I personally think is stupid? Converting a diesel engine platform to run on CNG/LNG. It makes no sense to use a block and reciprocating assemply that it strong enouigh for compression-ignition in a spark ignition engine. All that extra mass serves no purpose whatsoever. Using something similar to the old gasoline big blocks could result in an engine that has all the power, economy, and reliability at much less size and weight. Yes, I still say that a new big block natural gas engine based on the block and rotating assembly of the old Super Duty engines would be well received in the marketplace. With modern design heads, intake, exhaust, and fuel delivery systems you could have engines in the 7.5 to 9 liter class with good power and torque characteristics as well as durability. But it would be an expensive undertaking, and I do not see a mainstream engine builder, let alone Ford or GM, being willing to spend the money. Hey, even the big old GMC V6 block and rotating assemblies would be a good foundation. Quote Link to comment Share on other sites More sharing options...
Bob Rosadini Posted August 31, 2012 Share Posted August 31, 2012 Well guys, can someone give a good explanation of the difference between CNG (compressed) and LNG (liquified) applications? The Ford Roush vehicles are CNG correct. Heavy applications are LNG right? It looks like all the Westport applications for HD are LNG. And it looks like the Chinese engine they offer is a diesel block configuration. I'm gettig the impression that CNG vs LNG is aimed at two different markets/applications. Quote Link to comment Share on other sites More sharing options...
twintornados Posted August 31, 2012 Share Posted August 31, 2012 I would LOVE to see an older 4.9L I6 (last seen in 1996 F150) updated and powered by CNG/LNG...modern computer mapping in Fords "Big Straight 6" would be interesting indeed....hog it out to 5.5L or 6.0L and see what kind of power that would make for medium duty.....and don't forget the trick Aussie "crossflow" head design with direct gas injection... Quote Link to comment Share on other sites More sharing options...
7Mary3 Posted August 31, 2012 Author Share Posted August 31, 2012 (edited) Well guys, can someone give a good explanation of the difference between CNG (compressed) and LNG (liquified) applications? The Ford Roush vehicles are CNG correct. Heavy applications are LNG right? It looks like all the Westport applications for HD are LNG. And it looks like the Chinese engine they offer is a diesel block configuration. I'm gettig the impression that CNG vs LNG is aimed at two different markets/applications. Not exactly. Heavy vehicles are available as both CNG and LNG. The primary difference is how the natural gas is stored on the vehicle (compressed to 3000 psi or condensed to a liquid at low temperatures) and the refueling facilities. The engines are the same, and both burn natural gas. Our CNG Freightliners use the same Cummins/Westport ISL-G that the local bus line uses in their LNG NABI transits. The advantage of LNG is longer range from the same storage volume (which makes LNG a bit more popular in vehicles where range is important) and the advantage of CNG is less sophisticated (and less expensive) refueling facilities (making CNG more popular for municipalities and utilities). Edited August 31, 2012 by 7Mary3 Quote Link to comment Share on other sites More sharing options...
7Mary3 Posted August 31, 2012 Author Share Posted August 31, 2012 (edited) Yes, I still say that a new big block natural gas engine based on the block and rotating assembly of the old Super Duty engines would be well received in the marketplace. With modern design heads, intake, exhaust, and fuel delivery systems you could have engines in the 7.5 to 9 liter class with good power and torque characteristics as well as durability. But it would be an expensive undertaking, and I do not see a mainstream engine builder, let alone Ford or GM, being willing to spend the money. Hey, even the big old GMC V6 block and rotating assemblies would be a good foundation. I agree, but I think the economics may change as CNG and LNG become the fuel of choice for commercial truck and bus fleets. Give it some time! P.S.- there's a 10.3L V-8 CNG/LNG engine under development as we speak. Edited August 31, 2012 by 7Mary3 Quote Link to comment Share on other sites More sharing options...
Bob Rosadini Posted August 31, 2012 Share Posted August 31, 2012 Not exactly. Heavy vehicles are available as both CNG and LNG. The primary difference is how the natural gas is stored on the vehicle (compressed to 3000 psi or condensed to a liquid at low temperatures) and the refueling facilities. The engines are the same, and both burn natural gas. Our CNG Freightliners use the same Cummins/Westport ISL-G that the local bus line uses in their LNG NABI transits. The advantage of LNG is longer range from the same storage volume (which makes LNG a bit more popular in vehicles where range is important) and the advantage of CNG is less sophisticated (and less expensive) refueling facilities (making CNG more popular for municipalities and utilities). Thx 7m-good info- and I would imagine LNG requires much less cu.ft of frame space for a tank with eq Not exactly. Heavy vehicles are available as both CNG and LNG. The primary difference is how the natural gas is stored on the vehicle (compressed to 3000 psi or condensed to a liquid at low temperatures) and the refueling facilities. The engines are the same, and both burn natural gas. Our CNG Freightliners use the same Cummins/Westport ISL-G that the local bus line uses in their LNG NABI transits. The advantage of LNG is longer range from the same storage volume (which makes LNG a bit more popular in vehicles where range is important) and the advantage of CNG is less sophisticated (and less expensive) refueling facilities (making CNG more popular for municipalities and utilities). Thx 7m-good info. And I would imagine an LNG option requires much less cu. ft. of frame space to accomodate an equivalent volume of fuel to get the same range. Is the tank weight-again assuming equivalent range-greater for LNG vs CNG? I have heard that in an 80,000 lb state, an LNG tractor in gasoline transport service will require a payload reduction of 300 gallons! That is huge and says the weight penalty is like 1800 lbs vs. diesel. Quote Link to comment Share on other sites More sharing options...
Edstock Posted August 31, 2012 Share Posted August 31, 2012 there's a 10.4L V-8 CNG/LNG engine under development as we speak. Made by whom? Mahindra? Navistar? Quote Link to comment Share on other sites More sharing options...
7Mary3 Posted August 31, 2012 Author Share Posted August 31, 2012 (edited) Made by whom? Mahindra? Navistar? You are funny! The 10.3L is by a company called Origin Engines. They are an industrial engine supplier. Their 10.3L is loosely based on the old Chevy Big Block. It is currently being produced as an irrigation engine, but I hear plans are underway to get it certified as a highway engine. We'll see if this amounts to anything, but even if it doesn't I think there are others out there. Edited August 31, 2012 by 7Mary3 Quote Link to comment Share on other sites More sharing options...
7Mary3 Posted August 31, 2012 Author Share Posted August 31, 2012 (edited) Thx 7m-good info- and I would imagine LNG requires much less cu.ft of frame space for a tank with eq Thx 7m-good info. And I would imagine an LNG option requires much less cu. ft. of frame space to accomodate an equivalent volume of fuel to get the same range. Is the tank weight-again assuming equivalent range-greater for LNG vs CNG? I have heard that in an 80,000 lb state, an LNG tractor in gasoline transport service will require a payload reduction of 300 gallons! That is huge and says the weight penalty is like 1800 lbs vs. diesel. Yes, a CNG fuel system does add significant weight. All the more reason for a purpose-built (non diesel conversion) spark-ignition engine! Edited August 31, 2012 by 7Mary3 Quote Link to comment Share on other sites More sharing options...
Edstock Posted August 31, 2012 Share Posted August 31, 2012 You are funny! The 10.3L is by a company called Origin Engines. Thank-you. Interesting engine. Quote Link to comment Share on other sites More sharing options...
theoldwizard Posted September 3, 2012 Share Posted September 3, 2012 Not exactly. Heavy vehicles are available as both CNG and LNG. The primary difference is how the natural gas is stored on the vehicle (compressed to 3000 psi or condensed to a liquid at low temperatures) and the refueling facilities. The engines are the same, and both burn natural gas. Our CNG Freightliners use the same Cummins/Westport ISL-G that the local bus line uses in their LNG NABI transits. The advantage of LNG is longer range from the same storage volume (which makes LNG a bit more popular in vehicles where range is important) and the advantage of CNG is less sophisticated (and less expensive) refueling facilities (making CNG more popular for municipalities and utilities). Very accurate, with one major omission ! LNG system are MUCH more expensive to install. From the pictures I have seen, the pluming/cooling is a nightmare. I'm no expert, but I believe that LNG system actually allow the liquid to "boil off", creating CNG. After that the systems are identical. Quote Link to comment Share on other sites More sharing options...
theoldwizard Posted September 3, 2012 Share Posted September 3, 2012 But, you know what I personally think is stupid? Converting a diesel engine platform to run on CNG/LNG. It makes no sense to use a block and reciprocating assemply that it strong enouigh for compression-ignition in a spark ignition engine. All that extra mass serves no purpose whatsoever. Using something similar to the old gasoline big blocks could result in an engine that has all the power, economy, and reliability at much less size and weight. I'm not certain what manufacturer you are referring to, but I believe the Cummins/Westport system is not "spark ignited". In fact, a small amount of diesel is injected "at the right time" to ignite the air/gas mixture. The side benefit of this system is a "limp home" if the CNG system fails. Quote Link to comment Share on other sites More sharing options...
7Mary3 Posted September 3, 2012 Author Share Posted September 3, 2012 (edited) Very accurate, with one major omission ! LNG system are MUCH more expensive to install. From the pictures I have seen, the pluming/cooling is a nightmare. I'm no expert, but I believe that LNG system actually allow the liquid to "boil off", creating CNG. After that the systems are identical. Absolutely! And you are correct, the engine runs on 'boiled off' LNG, which is natural gas. Edited September 3, 2012 by 7Mary3 Quote Link to comment Share on other sites More sharing options...
7Mary3 Posted September 3, 2012 Author Share Posted September 3, 2012 I'm not certain what manufacturer you are referring to, but I believe the Cummins/Westport system is not "spark ignited". In fact, a small amount of diesel is injected "at the right time" to ignite the air/gas mixture. The side benefit of this system is a "limp home" if the CNG system fails. Westport has a diesel pilot injection CNG engine under development. Our new Freightliners at work use the Cummins/Westport ISL-G which does have spark plugs: http://www.cumminswestport.com/content/430/ISL%20G%20-%20%204971373_6_2012.pdf Personally, I think diesel pilot injection is a very expensive set of spark plugs and makes it more complicated to control ignition timing. And, judging by the size of the diesel fuel tank on trucks so equipped and the fact that the injectors are sized for starting the engine and not much else, I think the 'limp-home' claims are somewhat dubious. Quote Link to comment Share on other sites More sharing options...
Joe771476 Posted September 3, 2012 Share Posted September 3, 2012 Latest Automotive News mag has an ad for Ford commercial leasing and it has a pic of a 2012 Taurus and an F650 dump. In School Bus Fleet mag, there's a Bluebird Vision bus ad with the Ford oval and Roush Cleantech logos touting the propane technology. First Student Bus Co. in Portland OR took delivery of 86 of these Bluebird propane-powered Visions. I'm just wondering that if Bluebird has the sole rights to the Ford/Roush propane engines in their Vision bus chassis, will we see a Ford cowl/chassis ever again? Thomas (Daimler) uses Freightliner (Daimler) conventional cowl/chassis and International uses their own cowl/chassis for their bus bodies. So who's left for Ford to team up with? Quote Link to comment Share on other sites More sharing options...
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