Ford 7.3L GASSER!!

BigToe wrote:

parker.rowe wrote:

BigToe wrote:
The 6.8L V10 has driven the RV industry for the last 20 years... in Class A motorhomes, Class C motorhomes, Class B vans, E Series ambulances that rush us to the doctor, and F Series trucks... from the F-250 all the way up to the F-750.

For over two continuous decades in a row, the overhead cam 6.8L Triton V10 has provided the power and proved itself... without a lot fussyness or fan fare.

Where's the love?

I don't think anyone said anything negative about the 6.8...but time marches on.

Hopefully this engine will be a worthy successor.

Carbed big blocks drove the RV industry for years before the 6.8 came around, but no one is looking to go back to those.

Yes, but the overhead cam, coil on plug ignition, sequential multiport fuel injection, long intake runner Triton V10 was a very obvious leap forward in engine technology over the carbureted big blocks in just about every engineering aspect and angle.

What's different about the push rod 7.3L is that Ford appears to be going backward technologically (presumably to save production costs), while selling the new motor as a leap forward. It isn't.

Even Ford's chief engineer for the engine, Joel Beltramo, made it clear in a variety of ways that it was a step backwards on a number of fronts. Listening to his responses in the interview, he repeated a mantra that I will paraphrase as something to the effect of "we didn't think it was needed".

So why bring up the 6.8L? Because anyone looking at Class 4 to Class 7 chassis cabs at this 2019-2020 juncture may want to consider a purchase now, in order to get the tried and true Triton V10, that has proven to be reliable despite it having more complex valve, cam, and injection technology, and has proven to be potent despite it's smaller displacement.

The new 7.3L block is a step backward from today's casting materials, being made of regular old grey iron rather than compacted graphite iron. It is a push rod motor, rather than overhead cam. It isn't direct fuel injection, like the new 6.6L gas motor from GM that it will be pitted against competitively.

And the reason for all these backwards steps was because "it wasn't needed" for the application. And I'll bet it is a cheaper to produce, especially since the Triton V10 lost it's two Triton family stablemates it shared many common components with... 5.4L and 4.6L, both shuttered by 2014... that vastly expanded the economies of scale that justified production of the V10 Triton motor.

With the volume of the smaller sized Triton motors out of the equation, the per unit cost to produce the more complex V10 had to be a motivating factor in considering an entirely new solution with a simpler valve train. Selling the concept of "simpler" as a reliability benefit to buyers is an obvious way to explain away dumbing down the engine... but the fact remains that the more complex 6.8L was already reliable.

While Andre did broach the subject of any relationship that the 7.3L has with the 6.2L, I'd have to listen again to see if Beltramo indicated whether the 7.3L is based on a stroked and poked 6.2L. I don't recall how that question was answered, of if the topic derailed on a tangent.

Anyway, with 20 years of solid commercial service track record behind the Triton V10, other than that brief period of spark plug spitting that got resolved 15 years ago, it is difficult to understand why Ford is making a change to a motor that is actually NOT bringing 20 years of engine technology advancements to the table, but instead is going backwards a few pages.

I was at the Ford manufacturer's booth at a automotive industry event back in 2001, and heard some Ford engineers way back then muttering about wanting to go back to push rod V8s. This was when the Triton family was the staple motor in many Ford products, and 5.0 of the previous era was had been retired. In particular, the Ford folks I was talking to were a small subset of performance oriented guys who were responsible for making the Mercury Marauder happen. I probably understand just as little today as I understood then why the push for push rods.

But now, Ford will have pushrods, a valve train that in theory is more likely to produce more low end torque at lower rpms, which is the more likely call of duty that a truck buyer would demand from an engine in the intended applications... at the expense of a more mechanically efficient valve train, total valve opening area, and higher rpm horsepower delivered with smaller displacement.

That the 6.8L V10 sees duty in an F-750 at 37,500 GVWR, with a V, not a C, really is a testament to a great motor. However inexpensively Ford manages to built the new 7.3L, it will have some big shoes to fill. Despite the tempting on paper combo of a 7.3L with a 10 speed transmission, I think I'd still have a tough time deciding on whether it is better to grab a 6.8L while one still can.

It is not necessarily a cost issue as to why Ford went with a push rod design since that can be easily be transferred to the customer. A grand extra is a drop in the bucket compared to how much these trucks cost especially when comparing it to a diesel.

The main reason for push rod is size. This engine will be going into other things than HD trucks where engine size combined with the size of the cooling system needed to keep this engine's temp in check at it's higher power levels needs to be as compact as possible. There is a reason why push rod LS swaps are so popular because you can fit one in just about anything due to their compact size. So if the application does not require an engine that needs to rev to the moon to get its power and it needs to fit it in small places, push rod is the way to go.

Also, one of the main reason why you have all this tech is to meet fuel economy and emissions standards. GM probably designed the 6.6L to go into various different applications below 8,500 GVWR(Camaro, Corvette) so it needs direct injection and other tech to meet the requirements of those GVWR's. Ford more than likely designed this engine only for applications with a GVWR higher than 8,500 that do not have as much fuel economy and emissions requirements so that tech is not needed since it will provide no substantial benefit.