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I was able to see the new 7.3 in person. It’s a great looking engine. And best news, it measures around 25.75 inches wide and appeared to have the same transmission bolt pattern as our modulars. There are no power numbers yet, but this may be an option to finally give our cars some real cubes. What do you all think?

https://youtu.be/byfFB79S4Kk
 

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Ive been planning this to go into the SC since I heard about it
 

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I suppose I just don't see the point of a big cube engine in a modern car/truck.

Equal power and better efficiency can be had with smaller engines and forced induction.

Having owned a 455 powered 1974 Trans Am, the instant torque is nice, but it topped out around 4500rpm. I like being able to wind my modular out to 6500ish and hear it roar.

Different strokes for different folks I guess, nothing wrong with wanting a big engine, just not how I want mine i guess.
 

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I heard it is just for the three quarter + ton pickups.
Have to agree with others; it seems a little late to be bringing out a new push rod V8 when everything is going smaller these days. Ford should have done this back in the mid 2000s instead of making the V10, or the 5.4 3 valve failure.

It will be interesting to see if it gets put into anything else. Either way I am looking forward to seeing it get swapped into other cars. It must have some monster numbers behind it with having that large a displacement and new modern technology to boot.
 

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If this engine came out 20 years ago I’d be more excited about it for hot rodability, but as it is it’s only going to be installed in super duty’s and possibly in crate form for what? $10,000+? That kind of defeats any benefit to bellhousing pattern since a new trans would be a drop in the bucket anyway.

I do kind of admire the brazenness of Ford to release a 445 cubic inch iron OHV pushrod engine in a day and age that has already preemptively declared the internal combustion engine dead though. It’s also quite the about face to the unwavering commitment to OHC technology, perhaps the modular was best suited to car apps afterall...


but may this be an option to finally give our cars some real cubes.
460 swaps have been done before, and I’d wager with aluminum heads and EFI it would put out comparable power numbers to this mill, no you don’t have the variable cam(which isn’t near as effective as DOHC) and the bellhousing patternm is different but those are pretty benign negatives compared to the real negatives of a big block...

The weight distribution of a V8 MN12 is already 58/42, and putting in a massive lump of iron will do nothing positive for dynamics besides the instant half shaft snapping torque.

A 351w based stroker build can get you well into the 4xx displacement as well, but without as many downsides
 

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I'm happy with my 323.

Ya'll have fun with that there 445. :gapteeth:
 

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I suppose I just don't see the point of a big cube engine in a modern car/truck.

Equal power and better efficiency can be had with smaller engines and forced induction.
The reason the engine is as big (in displacement) as they have made it is so that it can achieve maximum efficiency with the given tune and operation range. The new 7.3 is being designed to run in the real-world, daily-drive range (well below 4k) and to run at true stoichiometric A/F mix as opposed to the industry standard of letting it get down as low as 12.5

In short, it's supposed to give you fat power/torque for workloads but also be relatively light on the fuel bill.

460 swaps have been done before, and I’d wager with aluminum heads and EFI it would put out comparable power numbers to this mill, no you don’t have the variable cam(which isn’t near as effective as DOHC) and the bellhousing patternm is different but those are pretty benign negatives compared to the real negatives of a big block...

The weight distribution of a V8 MN12 is already 58/42, and putting in a massive lump of iron will do nothing positive for dynamics besides the instant half shaft snapping torque.
Though I like the 460, it probably couldn't hold a candle to this new 7.3...

For starters the 7.3 is very well packaged, fitting 445ci and variable valve/oil tech into a space technically smaller than the 4.6/5.4/5.0 design. Head and piston tech has come a very long way since Ye Olde 385 Block, allowing for higher compression and better quench/flow/swirl, and with modern EFI ignition timing is spot-on perfect in the high-advance range (which is where this engine is being built to live).

Regarding weight, I'd wager this new engine to weigh the same or less than the factory 4.6 in our MN12.


ALL THAT BEING SAID.....

I do believe there will be a huge performance potential for this engine once folks figure out how to change the cam (and variable timing) and most importantly the ECU tuning. I can't speak for the head/runner design as it's a 2V setup and, though the ports are large, designed for low-end grunt along with the wrapped-up intake manifold runners in the valley, but I'm sure someone will figure out how to boost the snot out of it since the bottom end is being built very robust (was there any mention of the crank being forged?)
 

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All the reps at the Ford booth didn't give any info on the motor. So I'm eager to see the advertised bore/stroke, hp, weight, internals, etc sometime soon.

Even the two measurements that I made (approximately 25.75 inches wide and 27.25 inches from the rear of the block to the front of the harmonic balancer) I did using a a piece of string because I have seen zero specs given anywhere on these as of now.
 

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There is a video of a Ford rep showcasing a cutaway-model of the engine, explaining (in minor detail) some of the features of the new mill.

Also, confirmed the crank on the new 7.3 is forged.

 

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The reason the engine is as big (in displacement) as they have made it is so that it can achieve maximum efficiency with the given tune and operation range. The new 7.3 is being designed to run in the real-world, daily-drive range (well below 4k) and to run at true stoichiometric A/F mix as opposed to the industry standard of letting it get down as low as 12.5

In short, it's supposed to give you fat power/torque for workloads but also be relatively light on the fuel bill.

So like a typical big block. True stoich is the industry standard, it’s the basis of closed loop. Big blocks don’t need as much throttle to move about as opposed to a smaller displacement/boosted applications so they won’t necessarily see 12.5 on a commute as often, but they still will under high load/WOT situations. There’s no way around it.

Light on the fuel bill is relative. Big block fuel consumption tends to remain pretty much consistent no matter how aggressively or miserly it’s driven or the load, but it’s not necessarily good mileage.




Though I like the 460, it probably couldn't hold a candle to this new 7.3...

For starters the 7.3 is very well packaged, fitting 445ci and variable valve/oil tech into a space technically smaller than the 4.6/5.4/5.0 design. Head and piston tech has come a very long way since Ye Olde 385 Block, allowing for higher compression and better quench/flow/swirl, and with modern EFI ignition timing is spot-on perfect in the high-advance range (which is where this engine is being built to live).

Regarding weight, I'd wager this new engine to weigh the same or less than the factory 4.6 in our MN12.

The 460 is smaller than the 4.6 too, OHC and Hemi head V8s were never the paragon of space efficiency, the block and crank contains the bulk of the weight and to achieve this displacement it simply requires more iron/steel/aluminum. There’s a 60lb difference just between 4.6 and 5.4 bare iron blocks, all in deck height.

It’ll be lighter than a 385 series because of the aluminum heads and plastic intake of course, but there are aftermarket aluminum heads and intakes for the 460 too, which simultaneously bump compression and have that better quench/flow/swirl to boot. Port EFI intakes are widely available as well.


ALL THAT BEING SAID.....

I do believe there will be a huge performance potential for this engine once folks figure out how to change the cam (and variable timing) and most importantly the ECU tuning. I can't speak for the head/runner design as it's a 2V setup and, though the ports are large, designed for low-end grunt along with the wrapped-up intake manifold runners in the valley, but I'm sure someone will figure out how to boost the snot out of it since the bottom end is being built very robust (was there any mention of the crank being forged?)
I’m not saying a 460 is *better*, as there are of course inherent advantages to a truly modern design, but as a swap candidate into a car like a MN12 the pros and cons of either one will cancel each other out. The pro for the 460 is the blocks are cheap and easy to find and have a good selection of dedicated speed parts available for it. The 7.3 isn’t even out yet, and if swapped into a car in stock form it’s not going to be a great performance motor for it until the aftermarket catches up.
 

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So like a typical big block. True stoich is the industry standard, it’s the basis of closed loop.
True stoich is what the industry would LIKE to get at, but often times you'll find engines idling/running in the high 13's or lower. From the Ford rep's discussion, the new engine will try to run around 14.5 to 14.7 at all times, revs, and loads.

I’m not saying a 460 is *better*, as there are of course inherent advantages to a truly modern design, but as a swap candidate into a car like a MN12 the pros and cons of either one will cancel each other out. The pro for the 460 is the blocks are cheap and easy to find and have a good selection of dedicated speed parts available for it. The 7.3 isn’t even out yet, and if swapped into a car in stock form it’s not going to be a great performance motor for it until the aftermarket catches up.
Agreed, bang-for-the-buck a 460 will be light-years ahead. The 445 will not only be outrageously expensive, but will have to make do with near-stock performance until somebody bold enough steps forward to figure out the ECU.
 

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Put a wideband on it, and you'll see what XR7-4.6 is trying to tell you.

I've written a lot of tunes at this point, all on my cars, and you Want to see the afr drop at higher rpms; if not, it'll be pretty quiet on the tow home.
 

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I should mention, Ford has stated that they want to slot this engine somewhere between the current 6.2 and the revised for 2020 diesel, so wouldn't be much of a stretch to assume at least 380 hp and somewhere near 500 ft-lbs of torque out of this new engine.
 

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Put a wideband on it, and you'll see what XR7-4.6 is trying to tell you.

I've written a lot of tunes at this point, all on my cars, and you Want to see the afr drop at higher rpms; if not, it'll be pretty quiet on the tow home.
Oh no I completely understand what you guys are saying, but I'm just pointing at what is being suggested by Ford with regards to the new engine's behavior.

It's no secret that AFR has to come down to not only keep the engine from burning itself a fresh hole, but to also make power, but there is now a rush to develop extreme-lean-burning engines in order to combat increasing EPA regulation as well as compete with (and stay relevant against) the ever-increasing electric market. Mazda is one such brand, with their new SkyActive-X platform that's rumored to be some 14.x:1 compression or higher and run as high as (I think) 22:1 AFR.
 

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The rep brushed on it but the main desire is to provide enough displacement where the engine doesn't see high loads despite pulling large physical loads, it's actually not new technology, Oldsmobile employed very similar engineering to their Turnpike Cruiser in the late 60s. The idea isn't about capping off enrichment at stoich, but pushing off enrichment from stoich as far off as possible for most situations, which is how they decided on this particular displacement.

Direct injection is the key ingredient to Mazda(and many others) lean running at cruise, but even they still run richer than stoich at WOT. The 7.3 is still conventional port injection system though, its big technologies, VVT and variable oil pump, are more about reducing parasitic losses and emissions.
 

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The only reason why I want this engine is because Ford hasnt made one like it in 20+ years and its a middle finger to the whole "go green" movement that made engines get smaller in the first place.
 

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Direct injection is the key ingredient to Mazda(and many others) lean running at cruise, but even they still run richer than stoich at WOT. The 7.3 is still conventional port injection system though, its big technologies, VVT and variable oil pump, are more about reducing parasitic losses and emissions.
Yeah there's no way to get around it, if you're gonna go full-hog on an engine you'll have to enrich until we can either figure a fuel or a hack that will make true stoich possible at any load and any speed... until then, we'll just keep pushing as close as we can to that limit.
 
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