Who will swap for the new 7.3 V8!

[engineermike]

Here’s your 2-valve port injected 6.2 for reference. If your 7.3 makes 1 hp/cid you can expect a similar curve.

2018 5.0 for comparison:

More everywhere even though it’s a “screamer” car motor.

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[Fatguy]

See if you can follow the bouncing ball....the current 6.2 in the 3/4 ton makes 1 hp/cid. If we maintain that ratio (both are 2 valve, pfi truck motors), the 7.3 would have 450-455 hp. Could it be 482? Maybe. The problem with single cam 2-valve engines like the 6.2, 7.3, sbc, bbc, bbf, etc...is that they inherently have narrow rpm ranges. Dohc with tivct has a huge advantage when it comes to breadth of rpm range, but I digress. Anyway, you can’t add top end power without sacrificing bottom end. Now, take a look at the 6.2 truck motor power curves. They, due to the inherent narrow rpm range, are surprisingly weak below 3500 rpm. In fact, the 1.2 liter smaller “screaming” 5.0 makes more torque at 2000 rpm. So you’re saying the 7.3 will make even more power/cid than the current 6.2. Possibly, but that will give it an even more exaggerated lack of performance below 3500. Sadly, if your star engine makes the same or more power than the 5.0, it will be a terd until about 3500 rpm.

We only need the low end of the rpm range as far as I’m concerned and sacrifice the high end. There are Mustangs for the track stars in the GT 350. The usual GT owner would be fine with a properly set up 2 valve big block. You guys kill me in that everyone and his mother here is buying tunes but if we swap the truck motor into the Stang we have to keep all parameters for the hauling trucks. Give the motor a chance!


There is an army of guys here that drove 2 valve V8s and loved them - me included. If I woke up next year with a big bow on the hood of my car and the 7.3 underneath I wouldn’t be crying and stomping my feet in despair. I’m betting a lot more guys like me would feel the same as well.

 

[Fatguy]

Dude, you seriously haven’t a clue what you are talking about. Gas direct injection has higher particulate emissions than port injection. The epa is currently moving to require particulate filters on gdi cars as we speak due to the high particulates. Port injection did not have this problem. Gdi was added to enable higher cylinder pressures, which allows engine downsizing and higher compression for better fuel efficiency, NOT to reduce particulates.

For stratified yes so I give that argument to you. My bad.

 

[martinjlm]

Nobody really wants cylinder deactivation in performance cars. Direct injection was added to reduce particate emissions. It’s an engine and one of the few V8s we have left.

Ford designed the engine for TRUCKS. Light Duty trucks make very good advantage of cylinder deactivation, because the amount of time they need all 8 cylinders is minimal. Heavy Duty trucks (like the ones Ford designed the 7.3L for) spend more of their operating time at load, thus no cylinder deac. Should also note that Direct Injection DOES NOT reduce particulate emissions.........it CAUSES them. This is why the next emissions tech coming to DI gas engines will be GPFs....gas particulate filters.

 

[CrashOverride]

This is just as false as, well, most everything else you’ve posted.

DI increases particle emissions just as you said. Look at any DI-only tailpipe an see all the black soot if you don't believe us. Or, look here:

http://www.engr.ucr.edu/~heejung/publications/2014-01-1451.pdf

"Aakko and Nylund [7] found that particle mass emissions for a gasoline DI vehicle were an order of magnitude higher than for a PFI vehicle for the European 70/220/EEC drive cycle."

The particulate problem is so bad, that many expect that particulate traps will soon be required for gas engines. DI is for better combustion control. You can run a rich light-off, followed by a lean flame kernal and it works. PFI would have problems completely burning the lean part, and so it would knock at the same compression ratio. Again, if you don't believe me, look at the compression ratio jump of similar engines when they convert from PFI to DFI. The high CR one can pump into a DFI turbocharged engine would simply blow up if you tried it with the same AFR in a PFI engine.

 

[engineermike]

We only need the low end of the rpm range as far as I’m concerned and sacrifice the high end.

Yep, you missed the point. You keep spouting numbers like “482 hp”, which is >1 hp/cid. You aren’t going to get >1 hp/cid out of a 2-valve pushrod motor without killing the bottom end torque. If you want your massive low-end torque off-idle, then this thing is going to only make around 0.8 hp/cid (~360 hp).

 

[Fatguy]

Yep, you missed the point. You keep spouting numbers like “482 hp”, which is >1 hp/cid. You aren’t going to get >1 hp/cid out of a 2-valve pushrod motor without killing the bottom end torque. If you want your massive low-end torque off-idle, then this thing is going to only make around 0.8 hp/cid (~360 hp).

Actually that is fine by me. I never was one to chase horsepower. The fox body motors were some of the fastest on the street and the horsepower number was lower than reality and nobody cared. Same with my 1995 LT1 in that I was happy with the torque (until it started to leak oil from every orifice and the opti and the misfire - but I digress). It is nice to say it has all this horsepower but it is the torque that mattered to us ordinary folk. I still like the 7.3 engine as most of it is straight out of the 1980s which is fine with me. I only care about how it drives and feels under my low rpm driving lifestyle. In fact every car I ever owned till this V6 Mustang - was a 2 valve pushrod V8 motor with or without roller rockers. As most here know, if I want modern I’ll buy a Tesla.


But thanks to you and the others for the lesson on DI and particulate emissions as I totally got that wrong. So wrong it’s actually embarrassing...

 

[engineermike]

The fox body motors were some of the fastest on the street and the horsepower number was lower than reality ....

The fox body 5.0 horsepower numbers were not lower than reality. 225 crank and about 190 rwhp. It adds up.

Same with my 1995 LT1 in that I was happy with the torque .

Funny thing here....the LT1 ran circles around the TPI 350 it replaced. However, it actually had 20 ftlb of torque LESS.

 

[engineermike]

Actually that is fine by me. ...

Just to be clear, you were spouting numbers like 482 hp. However, that kind of power would result in crappy low-end. To get low-end, the power would be limited to under 400, which you'd be "fine with". I don't think Ford is designing this engine based on your wants, though, so you'll probably be stuck with whatever they give you.

 

[Hack]

The theory is as follows.

Most people spend the life of their driving at low rpms - let’s say between 1200 and 2000 rpm. That is the reality. Just check it out yourself on your daily commute.

Truck motors put out most of their power at low rpms so you would probably enjoy the power of a truck motor more in typical day/to-day driving. You’re paying for it so you may as well enjoy it.

I sure as heck don't want to drive a performance vehicle daily on the road if that vehicle is set up so that I'm right in the power band all the time.

If would be like driving the GT350 around at 6,000 rpm all the time. Can you imagine how touchy it would be? Just breathe on the throttle and you'll spin out, especially if the roads are a little cold and wet.

I want to daily a performance vehicle that's EXACTLY like the GT350. Low torque and HP at low RPMs so that in low traction situations I can run at lower RPM and the vehicle behaves in a super calm manner - extremely streetable.

Then when I get to the track, wind the RPM up into the power band and it's a beast!

Your idea might work for a "performance" vehicle that is 80's fast, but not for a vehicle that can run like the modern V8s do.

 

[nastang87xx]

I'm not going to read all of this but you guys...you SERIOUSLY need to read up on why and how Ford got to the 7.3L displacement and what the math and data says about the application behind the fuel consumption and power strategy. This is NOT an engine that would be suitable for a 3800lb street car and it is not because the power isn't there. Why, you ask? Again, do some reading.

 

[Fatguy]

If would be like driving the GT350 around at 6,000 rpm all the time. Can you imagine how touchy it would be? Just breathe on the throttle and you'll spin out, especially if the roads are a little cold and wet.

As soon as I read that I wanted to shout that that’s what a lot of people want. If it gets cold or wet turn on the traction control. Some people are simple that way...

 

[Fatguy]

I'm not going to read all of this but you guys...you SERIOUSLY need to read up on why and how Ford got to the 7.3L displacement and what the math and data says about the application behind the fuel consumption and power strategy. This is NOT an engine that would be suitable for a 3800lb street car and it is not because the power isn't there. Why, you ask? Again, do some reading.

Yah it’s not like we couldn’t change things like a tune, intake, headers, heads, injectors, valves, rear gears, exhaust and anything else you could think of that everyone does all the time. How about a supercharger on this motor? I guess these mods are only for “approved engines” as stated by anonymous Mustang members in a Mustang message board. Making an engine is the hard part and Ford has given us a very simple engine to play with. Think of the possibilities instead of discounting it and then lamenting that the V8 is near extinction...

 

[engineermike]

Since supercharging is on the table, you know what would be awesome? A supercharged 32-valve dohc engine with direct injection, and 12/1 compression. Great torque at any rpm!

 

[Fatguy]

Since supercharging is on the table, you know what would be awesome? A supercharged 32-valve dohc engine with direct injection, and 12/1 compression. Great torque at any rpm!

The funny thing is if it can fit reasonably well in the Mustang, the aftermarket will get to work in all
manner of ways to change the engine for a Mustang friendly application. This isn’t an econo car project by any stretch of the imagination.


And I get it - 5.0 quip...

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