V-8 Power Stroke and I-6 Cummins

[cmckinney]

What are the benefits of the V8 over the I-6 and vice versa? Have a friend who has the Ford and says that he makes more HP and Torque than the Cummins so why is Cummins preferred over the Power Stroke?



-CM

 

[hammersley]

Now you did it?

This ott's be fun... ... .

 

[BV]

I-6 for pulling/v8 for racing

The I6 was build with low end torque and less moving parts so that it was dependable of longer periods of time. This is what makes them more suitable in long haul trucks and stationary power situations.



Honestly I can't think of any advantage to the v8 other than it turns up a higher rpm for racing and burns more fuel.



Even back in the oldn' days (like the 80's) I had a little 240ci I6 that would take a friends 352ci v8 and eat it for lunch in a pulling match.



I bought my I6 for all the reasons above and it's easier to service than the v8

 

[MJawsman]

Well I'm sure that you'll receive many replies to this question, but I'll tell you why I think your friend says those things. First of all, Ford is currently winning the horsepower and torque battle, but that wasn't always the case nor do I feel it will be again soon. The Ford by design has a shorter stroke. Short stroke motors have the ability to rev to a higher RPM, but why would anyone want a high reving Diesel motor? Diesels were designed to pull, and that's something the Cummins does very well. It has a much longer stroke and correspondingly more potential torque capability. Torque is what gets the load moving, horsepower maintains it. There are more reasons why the I-6 is better-not the other way around. Heck, if the Cummins was an 8 cylinder it would be 40 cubes bigger than the Ford! Tell your friend to divide the horsepower and torque numbers of each motor by the cylinder count and see who wins that war. Both are good motors, but the Cummins track record speaks for itself. It's overbuilt for our use, and it has the potential for over 1 million miles of relatively trouble free use. Check the competition, but don't be fooled by what's on the surface. Be sure to dig deep enough to see what their really made of.



Just my humble $. 02 opinon.

 

[mberry]

Originally posted by MJawsman

Well I'm sure that you'll receive many replies to this question, but I'll tell you why I think your friend says those things. First of all, Ford is currently winning the horsepower and torque battle, but that wasn't always the case nor do I feel it will be again soon. The Ford by design has a shorter stroke. Short stroke motors have the ability to rev to a higher RPM, but why would anyone want a high reving Diesel motor? Diesels were designed to pull, and that's something the Cummins does very well. It has a much longer stroke and correspondingly more potential torque capability. Torque is what gets the load moving, horsepower maintains it. There are more reasons why the I-6 is better-not the other way around. Heck, if the Cummins was an 8 cylinder it would be 40 cubes bigger than the Ford! Tell your friend to divide the horsepower and torque numbers of each motor by the cylinder count and see who wins that war. Both are good motors, but the Cummins track record speaks for itself. It's overbuilt for our use, and it has the potential for over 1 million miles of relatively trouble free use. Check the competition, but don't be fooled by what's on the surface. Be sure to dig deep enough to see what their really made of.



Just my humble $. 02 opinon.

What he said!Oo.

 

[Seed Guy]

Honestly i am not convinced that ford is winning any HP battle. Even if there factory sticker claims to have a higher HP rating. Through 2000 dollars at a Cummins and we will see who wins a drag. From a person who has had both, i would never go back to the ford V8. I have never seen a V8 diesel produce the kind of power an I diesel can. Our KP525 engine in a huge tractor is I so, my truck should be too.

 

[hammersley]

BS

Well what I mean is Bore and Stroke.



Bore Stroke DRY Weight

(inches)

Powerstroke 4. 11 4. 18 930 Lbs

ISB 4. 02 4. 72 962 Lbs



- The PS has Glow Plugs

- The PS doesn't have an injector pump but "smart injectors". They operate off the internal oil pressure of the engine. As such they are very fussy about any contaminates in the oil or foaming. Also you have 8 very complicated and I mean complicated little devices that are just waiting to screw up. They are also extremely expensive to replace and modify. You can buy a set of injectors for an ISB for the cost of abou 1. 5 of a PS.

- Count the # of Big Rigs that use V-8's if they are so good!

- If the PS is so powerful how come the little ISB dominates the Sled Pulls?

- Go to the Ford Page and look up CACKLE -

- Talk to a Ford guy and see what mileage they get...

- and more and more and more

 

[Mark_Kendrick]

What they said!!!!



I6s are naturally balanced, have 40% fewer parts, more main journals, gravity does not ovalize the bores. The list goes on.



like the GMC commercial... . for 98% of the population a V8 will do. Me, I'm a 2%er



Later,

Mark

 

[Gary - K7GLD]

#1. MOST of us buy our trucks for serious WORK - not drag racing,



#2. If V8 diesels were REALLY the superior design for serious WORK, why aren't there any in use in the 18 wheeler trucking industry?



#3. What diesel engine design IS used nearly exclusively in the trucking industry, and what maker is a MAJOR supplier of those engines? Inline sixes, MANY made by Cummins!



#4. How many of those superior, powerful International V8's do we see in those freight haulers? Zero, Nada - ZIP!



How much further need this discussion go?



The SAME design advantages that make inline long-stroke sixes the engine of choice in the trucking industry apply equally strongly in OUR trucks - economical operation, flexible power generation i. e. . easily upward adaptable for higher output while still maintaining economy and reliability, and a simplicity of basic design that reduces components, maintenance costs, and failure rates...

 

[MJawsman]

Originally posted by Seed Guy

Honestly i am not convinced that ford is winning any HP battle.

What I meant by HP battle was on paper. The new Ford is supposed to be 275/520 with the 6 speed. That beats our HO's 245/505. Seat of the pants is another matter entirely, and I'm afraid I don't have both vehicles in my corral for comparison. Everyone exaggerates ratings and has been doing it for years. And I think that Cummins has been much more conservative than either GM or Ford.



Again... JMHO!

 

['956Wheel]

My understanding of torque is leverage. It must be in an engines design, crank throw. So if you have 5. 9 in a six you can have less displacement and achieve more torque than a um say 7. 3 in an 8 cyl.



Kinda like a Harley vs rice rocket... if the hill is long enough the HD will get um.



H. P. is all about rpm's but TORQUE is about "duration of push".



More bang for your buck... thats why we pass um on hills. . Mom calls them downhill racers!



Mike

 

[work2muchplay2little]

How do you get a Cummins ISB in a Ford? You have to buy an F550 or above... . or do it yourself.

 

[Mallory]

A v8 engine has better balance, but an inline has greater stroke to bore ratio which means more torque (leverage) . An inline has greater crankshaft bearing surface area because of it's length(crank shaft). The numbers for torque are close with the ford at peak,but I but the average torque through the RPM range is much better with a dodge, the cummings torque curve is flatter hence higher average. So who really has more power? These are shade tree observations so don't take to seriously. brian

 

[4020Deere]

To really understand the reason why a V8 engine was ever even designed, you have to go back to 1932. Ford was the first maker of a V-configuration engine (flathead). If you do a little research, the ONLY reason for this was to be able to fit 8 cylinders where 4 used to be! The hoods on pre-1932 Ford cars & trucks were the same length as the post-1932 ones. The competition also had 8-cylinder engines, but were of an in-line configuration. Just look at the old "straight-8" Buick, Olds, etc. They were VERY long and required very long hoods. Fine for a high $ luxury car, but too much $ for an everyday car. Also, the V8 saved weight in the block, crankshaft, connecting rod, and intake manifold areas. So the concept of a V8 was NOT due performance al all. It was due to the necessity to fit a more powerful engine into a small package. Through the years, most heavy duty gas and diesel engines have remained of an in-line design. In the 1970's, V8 diesels had a brief popular period. But manufacturers went back to the in-line design for a number of reasons, including superior torque curves, engine longevity, less moving parts, etc. Now, most of the V-configuration heavy duty engines are that way due to space considerations, just like the first ones were (a 12 or 24 cylinder engine would be WAY too long if it were an in-line). If you look at the rest of the Navistar engine line, they're all in-line 6 cylinder engines also. But the Powerstroke is still a V8. I would suspect this is due to a number of reasons, but overall physical size and cost are probably the two main reasons why it has remained as Ford's diesel engine of choice. As you move up the line to the heavier Ford trucks (F650), the V8 dissappears and your back to a choice of Cat or Cummins, both being in-line 6 cylinders.

 

[Wolfgang]

A recent article in Trailer Life talks about Ford coming out with a 600ft lb motor in 2004, they asked DC about this and were told they could go beyond 600 very easily. (Course we know this is true). The diesel wars are not even close to being over. Isn't competition marvelous

 

[Gary - K7GLD]

UMMMmm - I agree heartily with all the above, except the part about Ford making the first production V8 - I'll hafta do some research on that one - I seriously doubt Ford was the first by a relatively long shot... .

 

[Gary - K7GLD]

WOLFGANG - yeah, the "claimed" power on the horizon appears to keep climbing - but what will be interesting is to see HOW MUCH of that pulling power remains available just off idle as the current Cummins does - that power that has to be obtain at relatively high RPM is pretty much counter to what many of us admire traditional diesels for... .



And THAT might just be ONE sacrifice of EPA-mandated diesel operation we might see as compared to past and currently available engines...

 

[rob10858]

if you want a cummins in a ford it's a 650 and above. i wish that our 550's had the isb option.

 

[TomGolden]

Originally posted by Gary - KJ6Q

#1. MOST of us buy our trucks for serious WORK - not drag racing,

Aw, come on Gary, the first place I met you was at the Sacramento Drag Strip :-laf Of course I believe you were just spectating that day, in your old truck...



But also, even on other diesel pickup web sites, I still haven't seen or heard of any Fords seriously drag racing. Have you all seen the various videos from May Madness drags last month



There is simply no way any PowerStroke can begin to compete with the likes of HVAC, CUMMINSTRKN, KeithLocklear (of DD) and some of the big boys. Talk about a smoke and speed show... :--) Oo. Oo. Oo.

 

[PZicha]

The Cummins 5. 9 is de-tuned a fair bit because of warranty issues or better put they are installed in our trucks on the bottom end of there power scales , I don't think there would be a power issue if we got the motorhome version 275hp 675ft/lb in our trucks from the factory... ask your friend if the powerstrokes are de-tuned also . when we Bomb our trucks we are only reclaiming what should of been there in the first place... Pete