7.3L V8 Godzilla now available as crate engine.

[edselford]

Well, the 6.2 SOC V8 is expensive to build and the parasitic losses are significantly greater than the 7.3 V8.  So if there is a need for a 6.2 or 6.3 liter, it would most likely be based upon the 7.3 design . Say 107.2 mm bore and 87 mm stroke, sort of like a Chevy 327 pumped up to a 383 V8. That would be an interesting high rpm high output V8!

We all could dream about this but the turbo solution has taken hold of the industry at least in SUV, car and light truck.

edselford

[akirby]

What would be the advantage of a 6.2 version that would justify building it?  Are there applicants where the 7.3 just won’t fit?  I can’t imagine it would be significantly better on fuel economy.  

[ESP08]

38 minutes ago, edselford said:

Well, the 6.2 SOC V8 is expensive to build and the parasitic losses are significantly greater than the 7.3 V8.  So if there is a need for a 6.2 or 6.3 liter, it would most likely be based upon the 7.3 design . Say 107.2 mm bore and 87 mm stroke, sort of like a Chevy 327 pumped up to a 383 V8. That would be an interesting high rpm high output V8!

We all could dream about this but the turbo solution has taken hold of the industry at least in SUV, car and light truck.

edselford

 

False.  If anything, the 6.2 has significantly less reciprocating valve-train mass. 

The 7.3 also has a timing chain running on nylon guides with a hydraulic tensioner. 

The 7.3 didn't go with pushrods for any technical benefit other than reduced physical size, less cost and the low RPM range of the engine made OHC less beneficial than in other apps.  

 

The 7.3 scaled down to 6.2 wouldn't be much to talk about.  

[7Mary3]

May not be a need for a smaller production 7.3L, there is a lower power version for the E series, which I assume will offer better fuel economy.  As far as I know the 6.2L is on the way out.

[jpd80]

1 hour ago, 7Mary3 said:

May not be a need for a smaller production 7.3L, there is a lower power version for the E series, which I assume will offer better fuel economy.  As far as I know the 6.2L is on the way out.

Exactly.

Now that the 7.3 can be produced in inree power levels, 310 HP, 350 HP and 430 HP, 

there's no actual need to have the 6.2 or even spend money  engineering a eplacement.

 

 

[akirby]

48 minutes ago, jpd80 said:

Exactly.

Now that the 7.3 can be produced in inree power levels, 310 HP, 350 HP and 430 HP, 

there's no actual need to have the 6.2 or even spend money  engineering a eplacement.

 

Given my experience with the 3.5LEB and 10 speed tranny more power does not necessarily equal worse fuel economy.

[Stray Kat]

8 hours ago, edselford said:

Well, the 6.2 SOC V8 is expensive to build and the parasitic losses are significantly greater than the 7.3 V8.  So if there is a need for a 6.2 or 6.3 liter, it would most likely be based upon the 7.3 design . Say 107.2 mm bore and 87 mm stroke, sort of like a Chevy 327 pumped up to a 383 V8. That would be an interesting high rpm high output V8!

We all could dream about this but the turbo solution has taken hold of the industry at least in SUV, car and light truck.

edselford

 

Okay it’s not that I don’t believe you but I for one wish you could expound on the statement comparing parasitic losses being greater on the 6.2 vs. the 7.3. 
 

I was under the impression that one of the greatest attributes of OHC engines is the reduction in valve train mass thus facilitating the use of far less spring pressure to control valve motion. 
 

Doesn’t that ^^^ have a net positive effect on parasitic loss?

[twintornados]

11 hours ago, edselford said:

Well, the 6.2 SOC V8 is expensive to build and the parasitic losses are significantly greater than the 7.3 V8.  So if there is a need for a 6.2 or 6.3 liter, it would most likely be based upon the 7.3 design . Say 107.2 mm bore and 87 mm stroke, sort of like a Chevy 327 pumped up to a 383 V8. That would be an interesting high rpm high output V8!

We all could dream about this but the turbo solution has taken hold of the industry at least in SUV, car and light truck.

edselford

 

Edited July 8, 2020 by twintornados

[jpd80]

7 hours ago, Stray Kat said:

 

Okay it’s not that I don’t believe you but I for one wish you could expound on the statement comparing parasitic losses being greater on the 6.2 vs. the 7.3. 
 

I was under the impression that one of the greatest attributes of OHC engines is the reduction in valve train mass thus facilitating the use of far less spring pressure to control valve motion. 
 

Doesn’t that ^^^ have a net positive effect on parasitic loss?

This side of 6,000 rpm, a pushrod valvetrain with roller lifters and long valve springs will do fine.

[edselford]

Well maybe this discussion includes what each of us would like to see, not what will actually happen.

A 6.2 or 6.3 version of the 7.3 would only be built with an aluminum block for F150/Mustang if at all!  There is no need for a smaller displacement 7.3 where the 7.3 is currently offered.

For a gas V8 that runs between 650 rpm to 6000rpm, a pushrod design is hard to beat from a cost, efficiency basis.

edselford

[2005Explorer]

I have been watching the TFL Truck maximum tow tests and the 7.3 absolutely dominates the competition. Good job to the engine team on this one!

[ESP08]

On 7/8/2020 at 2:46 PM, Stray Kat said:

 

Okay it’s not that I don’t believe you but I for one wish you could expound on the statement comparing parasitic losses being greater on the 6.2 vs. the 7.3. 
 

I was under the impression that one of the greatest attributes of OHC engines is the reduction in valve train mass thus facilitating the use of far less spring pressure to control valve motion. 
 

Doesn’t that ^^^ have a net positive effect on parasitic loss?

 

Bottom line, he's wrong.  

[edselford]

If you don’t believe me, find a ford or GM engine engineer and ask them the question.

I think you will find the engine spin torque from 650 to 6000 rpm is lower on the gm 6.2 versus the ford  6.2 SOC V8.

the area under the spin torque graph is basically the energy needed to overcome all friction and approximates the energy used up by the engine just to spin ! 
edselford

[jpd80]

43 minutes ago, edselford said:

If you don’t believe me, find a ford or GM engine engineer and ask them the question.

I think you will find the engine spin torque from 650 to 6000 rpm is lower on the gm 6.2 versus the ford  6.2 SOC V8.

the area under the spin torque graph is basically the energy needed to overcome all friction and approximates the energy used up by the engine just to spin ! 
edselford

And if it was truly a significant increase in resistance, the 6.2 SOHC Boss would have never seen the light of day,

Ford would have opted for a simpler cam in block roller follower pushrod Hemi set up.....but it didn't and here we are.

The same argument could be made for the Mod motors versus the GM V8s of the same era, I'm betting that those

parasitic losses were not a serious issue to Ford.

[edselford]

When the 6.2 SOC was designed, it was an off again and on again project to counter the GM 6.2 V8 and the Chrysler 5.7/6.1 V8 Hemi.

The plan included a 5.8 liter version for theMustsng that never made it!

At about the same time Ford was coming out with the ecoboost, first on the four cylinders and later on the 3.5 gen 1.

It is possible that Mustsng drove the overhead cam design because it would be inconsistent to have a high tech 4.6/5.0 DOC V8 and then offer. A higher hp pushrod engine!

I am sure there was great debate about SOC for the 6.2 and less debate for the 7.3.

You might be right that the parasitic losses between the two designs were insignificant in fords decision making! It may have been purely marketing!

when you are limited to 100 mm bore centers, you need 4 valve and overhead cams and higher rpm to make competitive power to a larger pushrod V8.

edsel ford

[jpd80]

13 hours ago, edselford said:

When the 6.2 SOC was designed, it was an off again and on again project to counter the GM 6.2 V8 and the Chrysler 5.7/6.1 V8 Hemi.

The plan included a 5.8 liter version for theMustsng that never made it!

At about the same time Ford was coming out with the ecoboost, first on the four cylinders and later on the 3.5 gen 1.

It is possible that Mustsng drove the overhead cam design because it would be inconsistent to have a high tech 4.6/5.0 DOC V8 and then offer. A higher hp pushrod engine!

I am sure there was great debate about SOC for the 6.2 and less debate for the 7.3.

You might be right that the parasitic losses between the two designs were insignificant in fords decision making! It may have been purely marketing!

when you are limited to 100 mm bore centers, you need 4 valve and overhead cams and higher rpm to make competitive power to a larger pushrod V8.

edsel ford

The GM 6.2 didn't appear until 2007 but yes, the 6.0 Vortec was an issue but the main stay in F150 was 5.4 and 5.3 in Silverado 1500. Where the product void existed was F250, it really needed a bigger engine but not too big as Ford still had the 6.8 V10 for F350 up. There was healthy discussion within for as to whether an enlarged 5.4 to 5.8 or 5.9 lifters would do the job of whether enlargement of  the architecture was justified. Plans for the smaller 5.8 were scuttled after Ford entered it's austerity period, the chiefs even asked if a slightly larger  push rod version of the boss would be enough.....if only they had known that OHC was over sold in a truck application and that buyers would have gladly embraced a modernised Lima 460.

 

Mustang was different, the 4.6 and 5.4 Mods were perfect especially when 3V 4.6 was an easy evolution and the DOHC was there as well.Thanks to the aftermarket, supercharging kits were becoming preferable over Ford needing  larger capacity engines

 

Edited July 19, 2020 by jpd80
Grammar and autocorrect errors

[edselford]

CThank You, Very good discussion on the subject. Like anything in the powertrain business, many factors affect the design of engines and transmissions!

When the 4.6 first came out on the Lincoln Town Car, it was pretty weak compared to the 302 V8 it replaced.  It took many years to make it better  from a performance perspective. I think ford actually worried about Toyota entering the full size truck business with a higher level tec engine. Also, people thought we would need front wheel drive cars with V8 engines. I’m sure this compromised bore center and that’s how we got 100 mm on the 4.6/5.4. Well we learned that high power and fwd don’t go together, but that was later on!

 

edselford

[jpd80]

2 hours ago, edselford said:

CThank You, Very good discussion on the subject. Like anything in the powertrain business, many factors affect the design of engines and transmissions!

When the 4.6 first came out on the Lincoln Town Car, it was pretty weak compared to the 302 V8 it replaced.  It took many years to make it better  from a performance perspective. I think ford actually worried about Toyota entering the full size truck business with a higher level tec engine. Also, people thought we would need front wheel drive cars with V8 engines. I’m sure this compromised bore center and that’s how we got 100 mm on the 4.6/5.4. Well we learned that high power and fwd don’t go together, but that was later on!

 

edselford

It's funny to look back and see how Ford twisted and tortured itself by locking into

engineering decisions that would later create unexpected consequences.

 

If Ford had just modernised its existing V8s, it would have achieved just as much

with a fraction of the bother. Maybe that's over simplistic but it seems that Ford

made life a lot harder for itself.

 

The reason for using the Mod V8s (FWD & lower emissions) were basically made redundant

by forced induction of smaller lighter I-4s and V6s as well as advances in emission modelling

and good three way catalytic converters.

 

Along that journey, people realised that V8s just weren't needed in most cars and light passenger

vehicles but trucks and large SUVs were another matter......

Edited July 19, 2020 by jpd80

[edselford]

You are very perceptive about what happened at ford! Sometimes it seemed like a new engine program was needed to justify the budget and engineering staff. The norm was always ten hours per day and only 5 hours on Saturday!

The money and benefits were great but 55 hours per week got old fast!

It seemed that the potential of the Lincoln Y block design was never realized and replaced by the MEL.too early,

The FE V8 were durable but except for the 427 and 428 cobra jet engines, were slow and used allot of gas. 390 always slower than the Chevy 327.

Two 351V8 engines (really 352) totally different except distributors and CID.

The 429 CJ was actually slower than the 428CJ but came too late to achieve its potential.

I think you know the story of the 4.6 family. I give the ford engineers allot of credit with the recent 5.0 V8!

The 6.2 Boss is another false start. When it first came out about ten years ago, about two years later I was trying to see if it could be punched out to 7.0 liters? I contacted someone from Rousch Engineering and was told not to spend too much time on it because it was probably going away!

People do the best they can given the parameters they have to work with. Like you said, sometimes the assumptions are wrong

edselford

[jpd80]

Ford tried to do too many things with the 6.2 and that's why I think it fell short of internal expectation,

the capacity wasn't enough to replace the 6.8 V10 and too big to survive in F150 without cylinder deactivation.

Had Ford just done the 7.3 Godzilla in 2011, a lot of other decisions like Ecoboost V6 and Coyote V8 may have

looked clearer.

 

The 6.7 Powerstroke was sold as an $8,000 cure all for owners that did a lot of heavy towing while

the gas option was relegated to a low cost part time lower load vehicle. The 6.8 was still there

but I get that the chiefs were annoyed that it was never effectively replaced. They never got that

simpler lower cost V8 that would fit in as many E and F applications as possible.

Edited July 20, 2020 by jpd80

[Bob Rosadini]

On 7/20/2020 at 9:03 AM, edselford said:

You are very perceptive about what happened at ford! Sometimes it seemed like a new engine program was needed to justify the budget and engineering staff. The norm was always ten hours per day and only 5 hours on Saturday!

The money and benefits were great but 55 hours per week got old fast!

It seemed that the potential of the Lincoln Y block design was never realized and replaced by the MEL.too early,

The FE V8 were durable but except for the 427 and 428 cobra jet engines, were slow and used allot of gas. 390 always slower than the Chevy 327.

Two 351V8 engines (really 352) totally different except distributors and CID.

The 429 CJ was actually slower than the 428CJ but came too late to achieve its potential.

I think you know the story of the 4.6 family. I give the ford engineers allot of credit with the recent 5.0 V8!

The 6.2 Boss is another false start. When it first came out about ten years ago, about two years later I was trying to see if it could be punched out to 7.0 liters? I contacted someone from Rousch Engineering and was told not to spend too much time on it because it was probably going away!

People do the best they can given the parameters they have to work with. Like you said, sometimes the assumptions are wrong

edselford

You seem to have a lot of good historical knowledge.  The 401-477 and 534 Super Duty engines that were first offered in '58 were offshoots of?

Lincoln?

[edselford]

The 401, 477 and 534 were mid range truck gas engines/ class 5, 6, 7. I can’t remember if they stretched into class 8. (Tandem drive axle)

They have nothing in common with any other Automotive ford/Lincoln engine family except the combustion chamber in the cylinder block like the Lincoln MEL and the Chevy 348/409/427.

(flat cylinder heads like the MEL)

I would guess the bore centers on these giant gas engines is around  5.25”

They were also used in large lake boats!

They came out about the same time as the Lincoln MEL series 4.90” bore centers replaced the Lincoln Y block, 4.63” bore center - same as the FE series bore centers! (352/390/406/410/427/428/332/360)
When I worked for the city of dearborn a teenager, most of our large trucks were 477’s.

Edselford

[Bob Rosadini]

7 hours ago, edselford said:

The 401, 477 and 534 were mid range truck gas engines/ class 5, 6, 7. I can’t remember if they stretched into class 8. (Tandem drive axle)

They have nothing in common with any other Automotive ford/Lincoln engine family except the combustion chamber in the cylinder block like the Lincoln MEL and the Chevy 348/409/427.

(flat cylinder heads like the MEL)

I would guess the bore centers on these giant gas engines is around  5.25”

They were also used in large lake boats!

They came out about the same time as the Lincoln MEL series 4.90” bore centers replaced the Lincoln Y block, 4.63” bore center - same as the FE series bore centers! (352/390/406/410/427/428/332/360)
When I worked for the city of dearborn a teenager, most of our large trucks were 477’s.

Edselford

So they were truly a unique block?  One thing I know for sure is they were not used in class 5 and 6.   (actually during that era I don't think the current weight classification system was used-I'm sure someone here can comment on that).   They lived during that time frame when big gas engines  were still a cost effective alternative to diesel but the feds killed them for sure with ever tighter emissions controls by the early/mid 70's. They were even used in the H series which was Fords first high tiltcab.  Basically a C series with an axle forward setting.

The Super Duty Tandems were T-850 and T-950 and when they first came out in '58, the highest rated  T-950 had a 15,000 lb front and a 38,000 lb. tandem.  But by '63 you could get a 950 with the full range of Rockwell tandems from 38,000 to 60,000!  Imagine a gas job with a 75,000 lb GVW!

And today, guys are arguing that the 7.3 doesn't have enough power for class 6 and 7!  By  '69, last year before Louisville I think you could get an 18,000 front with the 60,000 rer for a GVW of 78,000.  

 

[jpd80]

6 hours ago, Bob Rosadini said:

So they were truly a unique block?  One thing I know for sure is they were not used in class 5 and 6.   (actually during that era I don't think the current weight classification system was used-I'm sure someone here can comment on that).   They lived during that time frame when big gas engines  were still a cost effective alternative to diesel but the feds killed them for sure with ever tighter emissions controls by the early/mid 70's. They were even used in the H series which was Fords first high tiltcab.  Basically a C series with an axle forward setting.

The Super Duty Tandems were T-850 and T-950 and when they first came out in '58, the highest rated  T-950 had a 15,000 lb front and a 38,000 lb. tandem.  But by '63 you could get a 950 with the full range of Rockwell tandems from 38,000 to 60,000!  Imagine a gas job with a 75,000 lb GVW!

And today, guys are arguing that the 7.3 doesn't have enough power for class 6 and 7!  By  '69, last year before Louisville I think you could get an 18,000 front with the 60,000 rer for a GVW of 78,000.  

 

Deck height was 11.5" from memory and dry weight was ~1,030 lbs

She was a big horse with about 360 up and 490 lb ft but those numbers

are actually Medium Duty figures so very conservative.

 

 

 

[Bob Rosadini]

3 hours ago, jpd80 said:

Deck height was 11.5" from memory and dry weight was ~1,030 lbs

She was a big horse with about 360 up and 490 lb ft but those numbers

are actually Medium Duty figures so very conservative.

 

 

 

Well one of  my antique truck pals -"antique " pertains to "truck"-er sort of-sent me pix of  his latest White- a '51 W22.  White Mustang power-396 Cube flathead, 145 HP, 5spd/2spd rear.  This  was a very popular freight hauler  in its day.  And today we  have guys saying the 7.3 doesn't have enough for 750.  As I've posted before, I think the 7.3 has better numbers than the 401 and the 477!