coupe3w Posted March 13, 2021 Share Posted March 13, 2021 (edited) 5 hours ago, edselford said: I was also surprised by the 6.8 V8 announcement given how close it is to the 7.3. Although everyone is talking short stroke version of the 7.3, I think you will see a smaller bore version of the 7.3 say 103.4 X 101 for about 414 cubic inches. It’s just much easier to get to 6.8 than reinventing the wheel. ya except for ford 427, 428 cobra jet, 351 Cleveland and the current 5.0/5.2 DOC V8’s over the last 66 years, ford V8 on the street were not that competitive. I had a 1966 Ford Galaxie with a 352 that was faster than a 1966 XL 390 four barrel. I never had a production 390 that could beat a Chevy 327. the 4.6/5.4 were durable but slow. the 351 W used too much gas and never could compete with the Chevy 350. Ford made the 427, 428 and 429 engines at the same time for a while, also 351W and 351C at the same time. It was confusing! Lets not forget two different 4.6 SOC in Romeo Mi and Windsor engine plants. edselford Agree, the 260 - 351W cylinder heads just plain sucked back then. The Boss 302 / 351C went in the right direction. Today it's a whole new ball game with after market cylinder heads. Edited March 13, 2021 by coupe3w 1 Quote Link to comment Share on other sites More sharing options...
jpd80 Posted March 13, 2021 Share Posted March 13, 2021 6 hours ago, edselford said: I was also surprised by the 6.8 V8 announcement given how close it is to the 7.3. Although everyone is talking short stroke version of the 7.3, I think you will see a smaller bore version of the 7.3 say 103.4 X 101 for about 414 cubic inches. It’s just much easier to get to 6.8 than reinventing the wheel. As an old FE man, you'd recognise the 7.3's bore and stroke as being similar to putting a 428 crank into a 427. Not exactly the same dimensions but very close in a lower deck height engine. Very little is known about the 6.8, most assume that it's a shorter stroke using the same bore because that's the least disruptive change on an existing machining line but what if it's a clever rework of the boss 6.2 with bigger bore and diameter block. What if it's none of those things and something different again....... Quote Link to comment Share on other sites More sharing options...
edselford Posted March 13, 2021 Share Posted March 13, 2021 We just won’t know until it is offered in a vehicle we can buy. I was also surprised Ford did not increase bore centers from the 6.2 115 mm to something around 118 mm on the current 7.3 V8. I just wonder if dynamic fuel management make V8’s more CO2 efficient eliminating the advantage the V6 ecoboost have today? edselford 2 Quote Link to comment Share on other sites More sharing options...
jpd80 Posted March 14, 2021 Share Posted March 14, 2021 (edited) 31 minutes ago, edselford said: We just won’t know until it is offered in a vehicle we can buy. I was also surprised Ford did not increase bore centers from the 6.2 115 mm to something around 118 mm on the current 7.3 V8. I just wonder if dynamic fuel management make V8’s more CO2 efficient eliminating the advantage the V6 ecoboost have today? edselford The 7.3 looks like an engine developed using the Boss 6.2 as a starting point, kinda like how Coyote was developed from the 4.6 Mod engine, same but different. From what I understand, the 7.3 pushrod is everything that the chiefs wanted for Super Duty back in the 2000s, the 6.2 was a disappointment because it was too thirsty for F150 (CAFE) and not enough capacity for the SDs. The thirty year irony in all of this is that Ford probably would have been better off evolving its old pushrod engines The 4.6, 5.4, 6.8 engines worked out fine but the same OHC and VCT applied to Windsor and Lima families would have probably panned out way cheaper and with more interesting outcomes.... Edited March 14, 2021 by jpd80 2 Quote Link to comment Share on other sites More sharing options...
slemke Posted March 14, 2021 Share Posted March 14, 2021 3 hours ago, edselford said: We just won’t know until it is offered in a vehicle we can buy. I was also surprised Ford did not increase bore centers from the 6.2 115 mm to something around 118 mm on the current 7.3 V8. I just wonder if dynamic fuel management make V8’s more CO2 efficient eliminating the advantage the V6 ecoboost have today? edselford I would say it is close enough that Ford will provide more V8 options. There isn’t much difference in fuel economy between a 5.0 and 3.5EB in a ‘21 f150. I’d take either one. A year ago I would’ve spent the extra on a 3.5EB. 1 Quote Link to comment Share on other sites More sharing options...
slemke Posted March 14, 2021 Share Posted March 14, 2021 3 hours ago, jpd80 said: The 7.3 looks like an engine developed using the Boss 6.2 as a starting point, kinda like how Coyote was developed from the 4.6 Mod engine, same but different. From what I understand, the 7.3 pushrod is everything that the chiefs wanted for Super Duty back in the 2000s, the 6.2 was a disappointment because it was too thirsty for F150 (CAFE) and not enough capacity for the SDs. The thirty year irony in all of this is that Ford probably would have been better off evolving its old pushrod engines The 4.6, 5.4, 6.8 engines worked out fine but the same OHC and VCT applied to Windsor and Lima families would have probably panned out way cheaper and with more interesting outcomes.... Hindsight is 20/20. From what I recall, Ford expected the emissions requirements to get much stricter faster than what they did. This incorrect assumption led to some of the product decisions. In fighting between the groups didn’t help either. Both the 4.6/5.4 and 302/351 were far behind GM v8s at the time. The original 5.4L was a poor showing against the 350 Chevy. Mustang development was supposed to pay for the PI head development, but the truck group needed it so badly they paid for it and introduced it in the ‘99 F150. They also caught a break with GM going to a 5.3L volume engine and 6.0L premium. Otherwise, even the PI 5.4 and 4.6 would have been uncompetitive. As it was, GM kept raising the bar with the 5.3L and Ford needed to use more expensive 3valve heads to keep up. No idea if Fords head designers could have kept up with the Windsor. They were pretty far behind also. Some of that is certainly attributable to multiple v8 platforms. I did read that the person/team responsible for the coyote and voodoo heads developed the Godzilla heads. Maybe they have some new trick for the 6.8L. But, then that would mean Ford is stretching the v8 development dollars over 3 platforms. 1 Quote Link to comment Share on other sites More sharing options...
jpd80 Posted March 14, 2021 Share Posted March 14, 2021 (edited) All it means is that once developers finish one project, they switch to another.... The configuration of the Mod V8s and V10 was based on two important criteria, the first was to ensure that future emission regs could be met and the incredible misread that the Mod V8 would be needed for transverse FWD application. The latter of those two requirements lead to bore spacing and bearing widths being narrowed, removing the opportunity for capacity growth and less comfort margin with bearing wear and oil pump longevity in more extreme conditions. All of which were eventually overcome. It's fine to say my critique is 20/20 hindsight but a switched on corporate should have been critiquing its decisions and if wrong, correct them but guess what, Ford doubled down and just kept going, even the V10 vibration/imbalance problems were controlled. (In comparison, GM's venture into the Northstar was comparatively short lived) Edited March 14, 2021 by jpd80 1 Quote Link to comment Share on other sites More sharing options...
edselford Posted March 14, 2021 Share Posted March 14, 2021 Ya the requirement for including the V8 in transverse FWD compromised the basic design. Back then, GM was going all out to full size Front wheel drive sedans with only Cadillac having a V8 I do remember a lincoln fwd with the 4.6 that did not sell hardly at all! I actually had two Northstar V8 engines. One in a 2000 model year Seville STS and one in a Buick Lucerne some years later. They both were very strong engines. I had tremendous torque steer and always thought both vehicles should of been rear wheel drive. I never understood why the northstar was taken out of production? Also the new Cadillac 4.2 DOC hot valley turbo V8 looks like it is still born at GM. Everyone wants to go to electric vehicles in almost every segment edselford 1 Quote Link to comment Share on other sites More sharing options...
Stray Kat Posted March 14, 2021 Share Posted March 14, 2021 (edited) Whoa Nellie! Hold on a minute here. I’m not a fan of the Mods gigantic physical size but it would be hard to think of a more successful engine line. For example the V10 in both 2V and 3V versions is the darling of the gas powered RV crowd. It will outdo the 460 and 454 while still delivering a little better fuel economy. The 4.6 and 5.4 2V engines are easily 300,000 mile engines. The 3V has a couple unforced errors but they’re not terrible. They,re big and ugly but they DON’T use the bandaid solution of deactivating cylinders to meet EPA and CAFE targets like the comparable GM and Mopar engines use. (and they have proven to be troublesome in their own right) By virtue of the small tight bore with precisely controlled combustion qualities. The very thing that kept the Mods in that small bore long stroke architecture was also the thing that just forced the physical size of that thing to get out of hand. The long stroke long rod required a tallish deck while Ford used the bulkiest head design known to man. Specifically the cam over followers over the valve stems. Those heads are unusually tall. I personally think Ford could have put a nicer head like that on the 6.2 and had a smaller and more powerful engine in every version (4.6, 5.4, 6.8). Those 6.2 heads are very much like the old 427 SOHC heads in that the camshaft was between the valve stems and used a rocker arm over the cam to actuate the valves. Don’t get me wrong I love the idea of a big inch pushrod V8 to go with the brilliant Coyote engine but this whole 3V head could have been avoided and the Mod based V8’s would have been far more competitive with the newer GM and Mopar V8’s. Edited March 14, 2021 by Stray Kat 3 Quote Link to comment Share on other sites More sharing options...
slemke Posted March 15, 2021 Share Posted March 15, 2021 18 hours ago, jpd80 said: All it means is that once developers finish one project, they switch to another.... The configuration of the Mod V8s and V10 was based on two important criteria, the first was to ensure that future emission regs could be met and the incredible misread that the Mod V8 would be needed for transverse FWD application. The latter of those two requirements lead to bore spacing and bearing widths being narrowed, removing the opportunity for capacity growth and less comfort margin with bearing wear and oil pump longevity in more extreme conditions. All of which were eventually overcome. It's fine to say my critique is 20/20 hindsight but a switched on corporate should have been critiquing its decisions and if wrong, correct them but guess what, Ford doubled down and just kept going, even the V10 vibration/imbalance problems were controlled. (In comparison, GM's venture into the Northstar was comparatively short lived) The issue I see with having multiple platforms is support, on going refinement and improvement. If the development team is large enough and the volumes support it great. Multiple engine platforms gives a manufacturer greater ability to the a custom solution, but it is additional expense to update multiple engine families with the latest technology to stay relevant and meet government compliance. Mullally asked why Ford had so many engine programs. I think it was in reference to 2.0l 4 cyl engines. The northstar had a similar run to the 4.6/5.4 mod motors...1993-2011. Coyote picked up where the mods left off and GM just dropped the Northstar...but that was after they sunk money into making it a longitudinal engine. Sometimes development is just so far down the path with programs and customers dependent on a program there isn’t much choice but to keep going. Especially if the thought didn’t change on tighter emissions Regs right around the corner and the need for front wheel drive v8s. Turbos didn’t really gain widespread acceptance in the 90s and Ford didn’t have a large displacement premium v6 to use that could reach 250-300hp naturally aspirated. But then Ford went and cloned the Jaguar v8 for the Lincoln LS. Plenty of bad decisions. The mod was really too big for some applications and not big enough for many others. The deck height and head design didn’t help. The coyote is several inches shorter and narrower then the 32v 4.6l it replaced. Had better packaging been done from the start, the bore spacing could have been increased and overall length remained the same. Another possibility for the tight bore spacing was v12 and in-line 6s. There were rumors of Ford testing a v12, but nothing came out of it. There was also the v12 powered GT90 concept car and 5.8l v10 Mustang prototype. Nothing came out of those either. it really wasn’t until the mid 2000s when Daimler Chrysler dropped the v10 in favor of the hemi with variable displacement that the tide turned. And in 2005/2006 Ford didn’t have money to develop much of anything. GM had the 8.1L, but it never took off and the 6.0l wasn’t quite big enough. The 6.8L v10 was the preferred gas engine for RVs. Ford spent money on the 6.2L v8, but it suffered a similar fate as the 6.0/6.2L in the GM lineup. Ford wasn’t too far off using the triton engine lineup. Mercedes was using a 3 valve per cylinder arrangement, so Ford was the only one. The development cost was amortized across many programs, so overall cost may not have been vary different. Ford being able to command premium pricing didn’t hurt either. 1 Quote Link to comment Share on other sites More sharing options...
jpd80 Posted March 15, 2021 Share Posted March 15, 2021 (edited) The 6.0 V12 was made and supplied to Aston Martin. And from memory, Mulally was targeting all the six cylinder engines (8 of them) Ford had at the time Edited March 15, 2021 by jpd80 1 Quote Link to comment Share on other sites More sharing options...
Sevensecondsuv Posted March 15, 2021 Share Posted March 15, 2021 On 3/13/2021 at 7:44 AM, slemke said: I did think about it. They have an even bigger V8. If big is good, bigger is better...so use a HO 7.3L. The 7.3L is narrower than a coyote, so width isn’t an issue. Length of the 6.8L isn’t any shorter than than the 7.3L, so not that either. That leaves height. Shouldn’t be an issue in Fseries, but maybe Mustang. Seems like a small market to me, especially considering buyers are already paying a premium for a supercharged predator. I also question the wisdom of thinking Ford will get a premium for this engine if it is a 6.8L pushrod making 500/500. It doesn’t scream premium, rather cost reduced/penny pinched. Ford has made enough questionable engine choices over my lifetime for me to be skeptical. Whatever they build I hope it works out for them as I am a stock holder. I could be completely wrong on the output of this engine and actual premium demand for it. I have no data and am just using my preferences. Time will tell. At this point, I’m not seeing the wisdom in the decision. I will reassess as more information is known about it and the applications for it. Getting ~700hp out of it would do it for me. The shorter stroke and deck height may be needed to achieve the high rpms needed to reach 700. A naturally aspirated high revving 700hp v8 would be unique enough to warrant the added development cost. My thoughts on the 6.8 is that it will essentially be a 7.3 intended for mustang/f150 performance applications. My guess is the 6.8L will feature an aluminum block and the displacement is the result of shortening the stroke a little to get a 7000 rpm powerband and possibly tightening the bore a little to get combustion efficient enough to pass emissions muster in a passenger vehicle class. Output of the 6.8 is going to be entirely dependent on heads/cam/intake. The 7.3 makes 435 hp with an inline valve head design and cam/intake designed for pulling stumps in a heavy truck. If they give the 6.8 a different head with splayed valves and a more aggressive cam and intake, then 600+ hp naturally aspirated is possible. I would think that'd be enough to stand out in the marketplace. Then again maybe the 6.8 is going to be overhead cam after all. It could be the long lost performance variant of the 6.2. Can you imagine coyote-style 4v heads with a 105 mm bore? That would be capable of 700+ hp !!! 2 Quote Link to comment Share on other sites More sharing options...
theoldwizard1 Posted March 15, 2021 Share Posted March 15, 2021 On 3/13/2021 at 7:04 PM, jpd80 said: The 7.3 looks like an engine developed using the Boss 6.2 as a starting point, kinda like how Coyote was developed from the 4.6 Mod engine, same but different. From what I understand, the 7.3 pushrod is everything that the chiefs wanted for Super Duty back in the 2000s, the 6.2 was a disappointment because it was too thirsty for F150 (CAFE) and not enough capacity for the SDs. The really big MISS on the 6.2L was they could not use it in the Medium Duty ! (Was it even offered in F450/F550 ?) On 3/13/2021 at 7:04 PM, jpd80 said: The thirty year irony in all of this is that Ford probably would have been better off evolving its old pushrod engines The 4.6, 5.4, 6.8 engines worked out fine but the same OHC and VCT applied to Windsor and Lima families would have probably panned out way cheaper and with more interesting outcomes.... The Modular family was sold to upper management as a flexible, "low cost" solution. The 4.6L and 5.4L (and maybe the 6.8L ?) could all be machined on the same line. Common pistons and connecting rods were supposed to be a big cost savings. Many other components (valve train, oil pump) were supposed to be shared between all engines. The 6.8L was a good engine ! Thirsty, but it got the job done. It was used extensively in motor homes. The big complaint there was it was load ! You had to spin it up to make power. I'm sure the data exists, but I would love to see the losses due to friction, etc when comparing a roller lifter pushrod valve train to a OHC roller finger follower. I don't know if one versus the other has any advantages of combustion chamber design or valve placement. 1 Quote Link to comment Share on other sites More sharing options...
ESP08 Posted March 15, 2021 Share Posted March 15, 2021 16 hours ago, edselford said: Ya the requirement for including the V8 in transverse FWD compromised the basic design. Back then, GM was going all out to full size Front wheel drive sedans with only Cadillac having a V8 I do remember a lincoln fwd with the 4.6 that did not sell hardly at all! I actually had two Northstar V8 engines. One in a 2000 model year Seville STS and one in a Buick Lucerne some years later. They both were very strong engines. I had tremendous torque steer and always thought both vehicles should of been rear wheel drive. I never understood why the northstar was taken out of production? The Northstar was just a disaster from the ground up, a thoroughly poor design. Soft blocks prone to cracking, head bolt threads prone to ripping out of the block causing head gasket failures, convoluted/failure prone timing chain drive, leaking bedplates causing oil pressure loss, etc. The 4V Modular was just drastically superior. Quote Link to comment Share on other sites More sharing options...
jpd80 Posted March 15, 2021 Share Posted March 15, 2021 (edited) 4 hours ago, theoldwizard1 said: The really big MISS on the 6.2L was they could not use it in the Medium Duty ! (Was it even offered in F450/F550 ?) The Modular family was sold to upper management as a flexible, "low cost" solution. The 4.6L and 5.4L (and maybe the 6.8L ?) could all be machined on the same line. Common pistons and connecting rods were supposed to be a big cost savings. Many other components (valve train, oil pump) were supposed to be shared between all engines. The 6.8L was a good engine ! Thirsty, but it got the job done. It was used extensively in motor homes. The big complaint there was it was load ! You had to spin it up to make power. I'm sure the data exists, but I would love to see the losses due to friction, etc when comparing a roller lifter pushrod valve train to a OHC roller finger follower. I don't know if one versus the other has any advantages of combustion chamber design or valve placement. The bigger advance came from low tension ring package, a conventional ring package in a SBC / SBF is approx 40 lb ft of drag, a low tension ring package reduces that to approx.15 lb ft. Remove rods, rings and pistons from an engine and just assemble the valve train on engines and I bet you could turn it over easy with a wrench, even a conventional flat tappet cam set up doesn't have all that much drag (it can't otherwise it would wear out super quick). Edited March 15, 2021 by jpd80 Quote Link to comment Share on other sites More sharing options...
theoldwizard1 Posted March 16, 2021 Share Posted March 16, 2021 19 hours ago, jpd80 said: Remove rods, rings and pistons from an engine and just assemble the valve train on engines and I bet you could turn it over easy with a wrench, even a conventional flat tappet cam set up doesn't have all that much drag (it can't otherwise it would wear out super quick). I would take that bet, especially on a non-roller cam follower ! I think it is a lot more than you would expect. For years, the "holy grail" has been electrically actuated valves. Not because of timing, but because of friction. Quote Link to comment Share on other sites More sharing options...
Sevensecondsuv Posted March 16, 2021 Share Posted March 16, 2021 The OHC engines I've assembled all turned over very easily (no wrench needed) when it was just the rotating assembly and no head / timing components in place. The need for wrenches came once the valvetrain, cam(s) and timing set were installed. Quote Link to comment Share on other sites More sharing options...
fuzzymoomoo Posted March 16, 2021 Share Posted March 16, 2021 1 hour ago, theoldwizard1 said: I would take that bet, especially on a non-roller cam follower ! I think it is a lot more than you would expect. For years, the "holy grail" has been electrically actuated valves. Not because of timing, but because of friction. Koennegsegg has an interesting electronic valve system that could have a future if they were willing to license it or something. Quote Link to comment Share on other sites More sharing options...
jpd80 Posted March 16, 2021 Share Posted March 16, 2021 2 hours ago, Sevensecondsuv said: The OHC engines I've assembled all turned over very easily (no wrench needed) when it was just the rotating assembly and no head / timing components in place. The need for wrenches came once the valvetrain, cam(s) and timing set were installed. I saw a YouTube where they measured the torque required to turn an engine with older conventional ring package and a newer low tension package. With the plugs removed, most engines can be turned over easy enough by hand so the amount of drag is comparatively not that much. I'm not saying there's no friction or resistance, just that it's not as much as most think. Quote Link to comment Share on other sites More sharing options...
Captainp4 Posted March 16, 2021 Share Posted March 16, 2021 Most of the resistance comes from the compression.. if you assembled correctly it's not much to turn over an engine without the heads on. Quote Link to comment Share on other sites More sharing options...
edselford Posted March 17, 2021 Share Posted March 17, 2021 International Harvester experimented with a mechanism on their DT466 that used hydraulics to move the valves open. I do not know what ever happened to that engineering project on their medium duty truck??? edselford 1 Quote Link to comment Share on other sites More sharing options...
slemke Posted March 17, 2021 Share Posted March 17, 2021 On 3/15/2021 at 2:22 AM, jpd80 said: The 6.0 V12 was made and supplied to Aston Martin. And from memory, Mulally was targeting all the six cylinder engines (8 of them) Ford had at the time The v12 was based on the duratec, not mod. He very well could have targeted the six cylinders also. There were plenty of them with significant overlap, or close enough performance to ask why so many. But, I recall 4 cyl engines also being a target. As each business unit had a different one of 2.0L. It was a while ago. 1 Quote Link to comment Share on other sites More sharing options...
slemke Posted March 17, 2021 Share Posted March 17, 2021 On 3/15/2021 at 11:08 AM, Sevensecondsuv said: Then again maybe the 6.8 is going to be overhead cam after all. It could be the long lost performance variant of the 6.2. Can you imagine coyote-style 4v heads with a 105 mm bore? That would be capable of 700+ hp !!! That would definitely stand out and be unique in the marketplace. I think it would lead to much better balanced handling than the supercharged offerings in that hp range now. Even if it was pushrod or SOHC, and produced 600-650hp, it would stand out enough to be warranted. Something around 500hp, though would be too close to Coyote performance. A dual injected, cross plane crank 5.2L, should be capable of 550hp. Voodoo was 526hp with port injection. No need for an all new engine of similar output. Quote Link to comment Share on other sites More sharing options...
slemke Posted March 17, 2021 Share Posted March 17, 2021 8 hours ago, fuzzymoomoo said: Koennegsegg has an interesting electronic valve system that could have a future if they were willing to license it or something. There is also a YouTube of some guy modifying a harbor freight predator engine to use an electronic valve system run by his laptop. It would eliminate the losses due to the throttle plate. Lets add it to Sevensecond’s 6.8L 4valve/cyl build. How wild of an engine can we build? Quote Link to comment Share on other sites More sharing options...
jpd80 Posted March 17, 2021 Share Posted March 17, 2021 The 500 hp suggestion I made earlier in the thread was simply adding 10% to the GM 6.2 figure, much better flowing head design opens up possibilities. 1 Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.