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The New 6.8L V8 Thread


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49 minutes ago, ESP08 said:

 

Perhaps 6.8 is smaller bore with cylinder deactivation 

The emission and fuel economy rules that apply to heavy duty trucks is different to CAFE

and assumes more constant loading situation in calculating amount of emissions as based on weight.

so cylinder deactivation is not a consideration….

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42 minutes ago, ESP08 said:

 

Perhaps 6.8 is smaller bore with cylinder deactivation 

 

I think you might be on to something.

 

Adding AFM to a pushrod V-8 is generally speaking easy, there is plenty of room for special lifters, ect..  OHC engines not so much, everything has to be located in the cylinder heads.  Maybe that's why the 6.2L never got AFM.  I have heard, but have not verified, the 7.3L uses GM LS lifters.  If that is indeed true a lot of the hardware may already exist to add AFM to the Godzilla family.     

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21 minutes ago, jpd80 said:

The emission and fuel economy rules that apply to heavy duty trucks is different to CAFE

and assumes more constant loading situation in calculating amount of emissions as based on weight.

so cylinder deactivation is not a consideration….

 

Not only does Ram have the feature on their 6.4L Hemi in the 4500's and 5500's, Cummins will be adding AFM to some of their engines as well.  Remember more stringent EPA/CARB and CAFE regulations are coming for commercial vehicles. 

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44 minutes ago, 7Mary3 said:

 

Not only does Ram have the feature on their 6.4L Hemi in the 4500's and 5500's, Cummins will be adding AFM to some of their engines as well.  Remember more stringent EPA/CARB and CAFE regulations are coming for commercial vehicles. 

They’re already here, the AFM is a workaround to get a reduction in emissions but the real challenge is the whole of the test.

https://www.govinfo.gov/content/pkg/FR-2016-10-25/pdf/2016-21203.pdf

From what I can find buried in the linked document is this from page 73499:

2020-2023

MD EPA CO2…………473g/bhp-hr

HD EPA CO2……..….447g/bhp-hr

2024-2026

MD EPA CO2…………467g/bhp-hr

HD EPA CO2…………442g/bhp-hr

 

NHTSA Fuel consumption Standard (gal/100bhp-hr)

2020-2023

MD…………4.6464

HD…………4.3910

2024-2026

MD…………4.5874

HD…………4.3418

 

I’m still trying to digest thes numbers but from it seems that power ratings and reductions in fuel used is the key

so whatever test cycle is used, manufacturers have to document and demonstrate actual reduction in fuel used.

I have a feeling that this is very hard to game and avoid the consequences of not doing continual improvement.

Edited by jpd80
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43 minutes ago, akirby said:

 

 

If you’re so close to the limit that a 7.3 works but a 6.8 doesn’t then you probably need the diesel anyway.

The difference is manufacturer needs to meet new emission/fuel economy improvement requirements

and while diesel everything would go a long way to solving that, Ford needs  its gasoline business as well.

The near $10,000 price hike for a diesel over gasoline is a tough sell for regular non fleet buyers…

 

Its almost going to be mandatory that gasoline direct injection comes into play to improve efficiency 

That would be a big help to the 6.8/7.3 gas V8 case..

 

I’m also surprised that a case can’t be made for the smaller Lion 4.4 V8 diesel  in F250/350

for that added fuel efficiency….maybe the cost of using it isn’t worth the return.

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Bob

sounds like you had a very fast Torino 428 CJ in a sleeper body, hatch back! I wish I could find a good one out there now.

I had a 1966 Ford Galaxie XL with a 390, 4100 four barrel carb, C6 with a 3.0 axle.

Car was  very slow compared to Chevy 327 power glide and my dad’s 352 Galaxie 500.

390 was very dependable and got retired at 149,000 miles with only water pump replacements.

There was a 1968 Ford Galaxie LTD and Cougar that offered a 427 ford side oiler block with hydraulic lifters only offered with the C6 rated at 390 hp. It performed almost as good as the 428 cobra jet!

when I started working at ford in 1969, ford made a 427, a 428 , 429, 462 and 460 engines and it seemed like all at the same time.

edselford

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18 hours ago, jpd80 said:

There’s a fast approaching need for better fuel efficiency/ emissions requirement  with F250 and F350,

the 6.8 could give them breathing space with that until the BEV Super Duty is ready…

I just watched The Fast Lane Truck Ford Lighting tow test on Youtube. They got 89 miles towing a typical RV trailer and spent as much time charging the thing as on the road. Is this what to expect from a BEV Super Duty? Aside from the urban cowboys and Californians, how many contractors, farmers, etc. would put their money down on a 3/4 ton with this level of performance.

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I'm not sure if this has been mentioned here in this thread, but there are already two separate tunings for the 7.3L gas V8 in the Econoline E-Series Cutaway and E-Series Stripped Chassis. There's the Premium tuning for those needing more power and towing and the Economy tuning for those seeking fuel efficiency and longevity. The Economy is derated/detuned version of the 7.3L V8 Premium and likely has other changes to it as well to improve fuel efficiency. There could be a possibility that something like this could be done to the upcoming Super Duty F-250 and F-350 refresh. Have the 7.3L Economy be standard on F-250 to replace the current 6.2L SOHC V8 and offer 7.3L Premium as option. The 7.3L Premium be standard gas V8 on the F-350 and F-450 or they may offer the 7.3L Economy on the F-350 as well. Perhaps they are planning this route for the upcoming Super Duty F-250 - F-450 pickups (I'm not talking about the Super Duty Chassis Cab) instead of the 6.8L that they had previously planned. That is if the 6.8L V8 has indeed been canceled like some rumored.

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If fuel economy and emission standards are tightening up on the heavier truck classes an aluminum block Godzilla makes sense. From the Ford Performance website, an aluminum block 351 weights 118 lbs compared to 195 lbs iron block. Applying that comparison to a similar sized Godzilla block will add up to significant weight savings for the vehicle.

 

An aluminum block Godzilla would need iron cylinder sleeves or a thicker cylinder wall with PTWA coating. This could account for a smaller displacement. A 3.6 mm smaller 103.6 mm bore with the same 101 mm stroke yields 6.8L.

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17 hours ago, jpd80 said:

The difference is manufacturer needs to meet new emission/fuel economy improvement requirements

and while diesel everything would go a long way to solving that, Ford needs  its gasoline business as well.

The near $10,000 price hike for a diesel over gasoline is a tough sell for regular non fleet buyers…

 

Its almost going to be mandatory that gasoline direct injection comes into play to improve efficiency 

That would be a big help to the 6.8/7.3 gas V8 case..

 

I’m also surprised that a case can’t be made for the smaller Lion 4.4 V8 diesel  in F250/350

for that added fuel efficiency….maybe the cost of using it isn’t worth the return.

The $10,000 premium is a tough sell for many fleet buyers as well. Plenty of fleet applications don't run annual  mileage to  justify it on a fuel cost basis.   As for the performance question, likewise the frequency of max GVW/GCW utilization is infrequent so a decent gas option is a good bet.

With the 10 speed going into 650/750, hopefully those added gear ratios will make the 7.3(6.8?) even more attractive.   Now if only they could solve the air compressor issue.

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The “all-new” Mustang EcoBoost has a higher stroke-to-bore ratio than previous 2.3L engine, now exceeding 1.2 (102/84), and a current Hyundai Atkinson engine has ratio of 1.35 , so  could 6.8L V8 follow this trend and be based on 100 mm Modular bore spacing by using diesel-like long stroke?  While it would require a taller deck height than 5.4L V8 and 6.8L V10, a new V8 with a stroke/bore ratio of 1.3 could displace up to 6.8L; provided objective is fuel efficiency (and lower emissions) rather than maximum power. 

 

If not too wide, such a large displacement naturally aspirated engine with Atkinson potential could also power future hybrid Super Duty.

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On 9/21/2022 at 5:25 PM, jpd80 said:

The difference is manufacturer needs to meet new emission/fuel economy improvement requirements

and while diesel everything would go a long way to solving that, Ford needs  its gasoline business as well.

The near $10,000 price hike for a diesel over gasoline is a tough sell for regular non fleet buyers…

 

Its almost going to be mandatory that gasoline direct injection comes into play to improve efficiency 

That would be a big help to the 6.8/7.3 gas V8 case..

 

I’m also surprised that a case can’t be made for the smaller Lion 4.4 V8 diesel  in F250/350

for that added fuel efficiency….maybe the cost of using it isn’t worth the return.

If Ford wanted a lower cost diesel, it should be an I6 or even an I4 not a smaller displacement V8.  GM was able to justify a 3.0L I6 diesel…and refine it.  I would think Ford could get at least as many takers for an I6 diesel in the super duty.  Maybe they are afraid it will take too many sales away from the 6.7L.

 

As for the 6.8L, I’m not seeing the need for it unless it brings something new to the table that dramatically increases efficiency over the 7.3L.  I get discontinuing the 6.2L to close an under utilized plant, but a 6.8L Godzilla seems redundant.

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58 minutes ago, slemke said:

If Ford wanted a lower cost diesel, it should be an I6 or even an I4 not a smaller displacement V8.  GM was able to justify a 3.0L I6 diesel…and refine it.  I would think Ford could get at least as many takers for an I6 diesel in the super duty.  Maybe they are afraid it will take too many sales away from the 6.7L.

The point being that the 4.4 already exists, an inline six diesel would have to be designed and developed…

The existing 6.7 diesel give a good increase  fuel economy in heavy trucks (about 30% better)

Ram when through the proposed smaller 5.0 diesel and really found little if any improvement over a gas V8.

 

 

Quote

 

As for the 6.8L, I’m not seeing the need for it unless it brings something new to the table that dramatically increases efficiency over the 7.3L.  I get discontinuing the 6.2L to close an under utilized plant, but a 6.8L Godzilla seems redundant.

If Ford is still proceeding with the 6.8, it would be to replace the 6.2 while providing better fuel efficiency that’s probably needed to stay in front of coming EPA increases in fuel efficiency……it might be more critical in things like F250 as they sell roughly twice as many of them as F350, drops again for F450 and then comes back for F550

Edited by jpd80
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21 hours ago, Rick73 said:
 

The “all-new” Mustang EcoBoost has a higher stroke-to-bore ratio than previous 2.3L engine, now exceeding 1.2 (102/84), and a current Hyundai Atkinson engine has ratio of 1.35 , so  could 6.8L V8 follow this trend and be based on 100 mm Modular bore spacing by using diesel-like long stroke?  While it would require a taller deck height than 5.4L V8 and 6.8L V10, a new V8 with a stroke/bore ratio of 1.3 could displace up to 6.8L; provided objective is fuel efficiency (and lower emissions) rather than maximum power. 

 

If not too wide, such a large displacement naturally aspirated engine with Atkinson potential could also power future hybrid Super Duty.

 

I would bet a lot of money that Ford won't deviate from Godzilla's 4.53 inch bore spacing.   

 

Though if fuel economy and emissions are the driving force for the 6.8 I could see the reduced displacement coming from bore diameter.    

That will generally improve BSFC figures -- and combined with cylinder deactivation may offer some tangible fuel economy benefits.   

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2 hours ago, ESP08 said:

 

I would bet a lot of money that Ford won't deviate from Godzilla's 4.53 inch bore spacing.   

 

Though if fuel economy and emissions are the driving force for the 6.8 I could see the reduced displacement coming from bore diameter.    

That will generally improve BSFC figures -- and combined with cylinder deactivation may offer some tangible fuel economy benefits.   

 

That seems most likely to me also based on Ford 3.3L, 3.5L, and 3.7L V6s sharing same stroke length; hence reducing Godzilla bore to +/- 103.5 mm is a real possibility.  Also, based on size and weight, an aluminum 6.8L Godzilla could have additional applications including HD Transit Cutaway and E-Series.  Higher GVWR Transit Cutaway in particular do not offer a naturally aspirated engine option as far as I know.

 

When Jerry Dias first mentioned 6.8L engine, he stated it was for Mustang and F-150, so information accuracy is questionable now that it is for Super Duty.  Other sources have mentioned 6.X L engine, so perhaps 6.8L size may not be that accurate either.  If it turns out to be smaller, in range of 6.4L (390 cubic inches) or smaller, then the possibility of new engine having bore spacing below 115 mm becomes more likely in my opinion.

 

A taller-deck Coyote Werewolf iron-block-based engine with 94 mm bore could reach 6+ liter displacement, and at +/- 80 lb-ft of torque per liter, 500 lb-ft would not require 6.8L.  I know cost would be higher than Godzilla, but an iron-block long-stroke Coyote with higher torque rating and improved fuel economy may be a possibility.  Cost and weight would be a little higher than Godzilla, but much lower than diesel option.

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10 hours ago, akirby said:

So in summary the only thing we really know about the new 6.8L is that it’s 6.8L and will appear in a Superduty.  ?

And I’d laugh my ass off if it wasn’t 6.8, Ford is fluid with a lot of its plans and the engine option talked about years ago may have changed  to something else. I often thought that a 7.3 offered with different power levels would achieve most things that commercial customers were seeking.

 

If Ford is making a smaller capacity Gozdzilla, then it’s because it sees a need, if not then it business as usual. The whole suggestion was blabbed by Jerry Dias two or three years ago as part of a UNIFOR agreement with Ford, clearly to guarantee more production from the 7.3 plant. It is possible that Ford simply produce more of the popular 7.3 and achieve that agreement.

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22 hours ago, jpd80 said:

The point being that the 4.4 already exists, an inline six diesel would have to be designed and developed…

The existing 6.7 diesel give a good increase  fuel economy in heavy trucks (about 30% better)

Ram when through the proposed smaller 5.0 diesel and really found little if any improvement over a gas V8.

 

The 4.4L was a premium v8 for Land Rover.  I doubt it was any cheaper to produce than the 6.7L scorpion.  My point was about reducing the cost of a diesel option.  The volume would need to be great enough to offset the development cost and remain cheaper than the 6.7L v8.  An I6 would almost certainly be less expensive to produce.  Whether or not the development cost spread out over the production run still keeps it cheaper is another question.  Considering how many engine options are available in the F150, I would bet Ford has considered additional options for the Super Duty and dismissed them.

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1 hour ago, slemke said:

The 4.4L was a premium v8 for Land Rover.  I doubt it was any cheaper to produce than the 6.7L scorpion.  My point was about reducing the cost of a diesel option.  The volume would need to be great enough to offset the development cost and remain cheaper than the 6.7L v8.  An I6 would almost certainly be less expensive to produce.  Whether or not the development cost spread out over the production run still keeps it cheaper is another question.  Considering how many engine options are available in the F150, I would bet Ford has considered additional options for the Super Duty and dismissed them.

The $10,000 option for the 6.7 is something made up by Ford and bears no resemblance to actual cost of the diesel, it is an assumed premium that diesel buyers will pay because they see long term advantage on fuel savings and better resale. Conversely, the 7.3 gas engine in comparison  is dirt cheap, so up front savings are there for those buyers. Maybe adding a hybrid battery is a better option…


The 4.4 diesel is now missing from the new 2023 Land Rover in a few markets that I checked (replaced by PHEV) I think it might have already been ended, there was talk of that in 2020. In any case, it was a long shot and I don’t think Ford is looking that direction, maybe Hybrid is a better way to fly with some of the Super Duty.

Edited by jpd80
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9 hours ago, jpd80 said:

And I’d laugh my ass off if it wasn’t 6.8, Ford is fluid with a lot of its plans and the engine option talked about years ago may have changed  to something else. I often thought that a 7.3 offered with different power levels would achieve most things that commercial customers were seeking.

 

If Ford is making a smaller capacity Gozdzilla, then it’s because it sees a need, if not then it business as usual. The whole suggestion was blabbed by Jerry Dias two or three years ago as part of a UNIFOR agreement with Ford, clearly to guarantee more production from the 7.3 plant. It is possible that Ford simply produce more of the popular 7.3 and achieve that agreement.

 

I had been thinking the same about the 7.3L V8 with few power levels. I mentioned this couple days ago in previous post here that's quoted below. In addition to my previous post, Ford does the same with the diesel for the Medium Duty with few power levels. I have wondered if this is what Ford has planned for the Super Duty, whether it's pickups, Chassis Cab, or both. I think the 6.8L V8 may have been cancelled as part of my own speculation. But I don't see why Ford Performance couldn't use the 7.3L V8 for the performance if they wanted to versus the 6.8L V8. We will see in a few days what Ford's actual engine plans are for the Super Duty.

 

On 9/22/2022 at 9:38 AM, pffan1990 said:

I'm not sure if this has been mentioned here in this thread, but there are already two separate tunings for the 7.3L gas V8 in the Econoline E-Series Cutaway and E-Series Stripped Chassis. There's the Premium tuning for those needing more power and towing and the Economy tuning for those seeking fuel efficiency and longevity. The Economy is derated/detuned version of the 7.3L V8 Premium and likely has other changes to it as well to improve fuel efficiency. There could be a possibility that something like this could be done to the upcoming Super Duty F-250 and F-350 refresh. Have the 7.3L Economy be standard on F-250 to replace the current 6.2L SOHC V8 and offer 7.3L Premium as option. The 7.3L Premium be standard gas V8 on the F-350 and F-450 or they may offer the 7.3L Economy on the F-350 as well. Perhaps they are planning this route for the upcoming Super Duty F-250 - F-450 pickups (I'm not talking about the Super Duty Chassis Cab) instead of the 6.8L that they had previously planned. That is if the 6.8L V8 has indeed been canceled like some rumored.

 

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