7.3 Gas Swap...Oh Yes.

[Angelo Voltura]

Well, for the time being dad's truck is powered with 1969 spec'd 1979 357w. Currently swapping over to Atomic EFI. The end goal with this red beast is a likely a crate engine, north of 500 horsepower bringing it back to its glory days of the early 90s when it really had a high powered motor in it.

Well, we've been talking about routes to take when that inevitably comes down the line in the next few years.

Over the years, every feasible engine you can think of has been discussed with this truck. One week, its "I should have put a Cleveland in it", another week "I almost put a 390 in it", another week "should have put a 460 in it". Lot of would have, should have, could have but never dids.

The last engine we looked at is the S374W crate engine available from Ford. 540 horsepower. However, I feel that engine is too rev happy and unsuitable in a truck. This 357w that is in the truck now was put together and thrown in in a matter of days and built for grunt and snow pushing.

This all changes now that Ford has come out with the 7.3 Godzilla gas job. I'm not sure how familiar you guys are with these engines yet, but working for Ford I have been playing around with them for about 6 months, and I tell you the Chevy LS guys better be shaking in their boots. I've talked on the Ford hotline, these engines are heavily, heavily based on a combination of the FE and Windsor engines, but primarily the Windsor engines. These are 6 bolt cross bolted main cast iron block, aluminum headed engines, with completely forged bottom ends that develop in stock trim, 430 horsepower @ 5,500rpm and 475tq @ 4,000rpm. I have already seen a set of headers and VERY mild (I stress mild) cam push this engine north of 580 horsepower. There is not reason why this engine cannot support 1700+ horsepower. I'm not going to get into it too much here, but if you get a chance, check out this article. If you tell me that it's not a modernized 351 Windsor, you are blind.


Regardless, the easy of swap-ability here is the point of this post. As of now I cannot get my hands on this engine any easier than any of you can, but from a swap point of view the low down is this thing practically will bolt into our trucks (they've already put these in Fox Mustangs and the motor mounts were eerily similar), especially if you were 6 cyl or small block powered to begin with. A standalone computer (which will be available once this comes out as a crate engine) will run this engine easily and if you have a fuel injected truck should be able to use your stock fuel pump. The cool part is it uses the standard modular engine bellhousing pattern so that means adapters for older transmissions are/will be available, however it will only run with an automatic transmission as the crank is not machined for a pilot bearing. This may change as there are rumors of some cranks having it (I have yet to see it) and the possibility of bolting a ZF6 to it is running rampid. Weight wise, it's marginally heavier than a 351W, around the same as a 351M or 400 and far less than a 460.

There will be next to no real fab work to get this engine to drop right in, and in theory with everything in a row could be done in a matter of days. This would be a FAR easier swap than an Ecoboost or Coyote. I have yet to be this excited for a new Ford engine in a long time, and right now it is something we are seriously considering.

I wouldn't rule this engine out as a swap item for you guys in the next 5 years or so.

[salans7]

A lot of people have been talking about the new 7.3 gasser. It will be interesting to see what else these engines will end up in.

[Nothing Special]

I've been tossing around ideas for a different engine for my '97 crew cab (or possibly a different ~'97 crew cab due to the rust).  I'm really not thrilled with the single digit mileage the 460/E4OD/4.10 combo delivers, and I don't think a diesel is a good option based on operating cost.  A mildly built 351W stroker is near the top of my list, but the Godzilla is REALLY intriguing!  I'm not interested in staying with an auto trans, so we'll need to see what happens there.

Any ideas what kind of real-world gas mileage that thing will deliver?  Personally I'm not interested in 1700+ or even 580 horsepower.  I'm more than happy with the power from my 460.  But I'm thinking that any engine Ford is using in newer vehicle has to do better on fuel than a 460.

[Gary Lewis]

Interesting, Angelo.  I hope it is a bit smaller than a 460 'cause the 460 in Big Blue is maxing out the space available.  Smaller would sure be better!

[Angelo Voltura]

Nothing Special wrote

I've been tossing around ideas for a different engine for my '97 crew cab (or possibly a different ~'97 crew cab due to the rust).  I'm really not thrilled with the single digit mileage the 460/E4OD/4.10 combo delivers, and I don't think a diesel is a good option based on operating cost.  A mildly built 351W stroker is near the top of my list, but the Godzilla is REALLY intriguing!  I'm not interested in staying with an auto trans, so we'll need to see what happens there.

Any ideas what kind of real-world gas mileage that thing will deliver?  Personally I'm not interested in 1700+ or even 580 horsepower.  I'm more than happy with the power from my 460.  But I'm thinking that any engine Ford is using in newer vehicle has to do better on fuel than a 460.

In the new trucks they arent seeing anything better than a 6.2. 12-14 city, 18 highway in a heavy 3/4 ton with a 6 speed.

Gary, dimensionally they 1-2" longer and wider than a Windsor. Just about anywhere you can fit a Windsor, this will fit. I did know the actual dimensions but cant remember the top of my head now. They are smaller than a 351M.

[Angelo Voltura]

I just checked; 2.5" wider and 1 1/4" longer than a Windsor dimentionally.

[Gary Lewis]

That does put them in the M-Block range, which noticeably smaller than the 460.  Cool!

[Nothing Special]

Angelo Voltura wrote

In the new trucks they arent seeing anything better than a 6.2. 12-14 city, 18 highway in a heavy 3/4 ton with a 6 speed....

WAY better than the 9~11 highway from my 460!  That's in a range I could live with.  It will be interesting to see what comes of this!

[Gary Lewis]

It is interesting to me that certain engines have such different ranges of economy.  The 460 is notorious for bad economy.  Why?  What makes one engine good and one bad?  Why is this new engine supposedly better than the 460 although having roughly the same displacement?

Is it just the build-up of several things, like intake runner size, valve size, rod to stroke ratio, exhaust port shape, etc?

[Angelo Voltura]

I think its more based on operating RPM. With 6 gears at 55mph your basically idling.

[Nothing Special]

I think it's a lot more than that.  There's no way a 460 is going to return 18 mpg highway with a gearing change.  Like Gary says and more, heads, cam, valves, intake, exhaust....  Much of what you can do aftermarket to improve power output actually improves engine efficiency.  A more efficient engine makes more power out of the amount of air and fuel it can pull through.  If you don't use that extra power the vehicle can use less fuel to do what it used to do with more.  Some engines have more room for improvement than others!

So could a 460 be built to give similar power and efficiency to a Godzilla?  I'm sure it could be better than stock, but it wouldn't be cheap or easy, and maybe not possible to get the whole way.

But most newer engines are inherently more efficient than those of a few decades ago.  The car companies have invested a lot of R&D to make that possible.

[grumpin]

That is MPG I would love to have with that kind of HP and torque!

I assume a lot of it comes from computers used in design and testing.

[Gary Lewis]

Right, Cory.  With the ZF5 behind the engine that's now in Cal's Rusty, Dad's truck got ~14 MPG running 65 MPH.  Our calculator says that with the 30" tires and 3.50 gears it was turning 1936 RPM.

But Big Blue's 460 is supposed to be turning 1795 at the same speed.  So if it was engine speed BB should get better than 15 MPG.  And we all know that's not going to happen.

When I get the EFI on Big Blue I'm going to be able to say "You can't get better MPG than this with a 460" since I'll have a fresh Scotty-built engine, EFI, ZF5, headers, etc.  And if I get 14 MPG I'm gonna be thrilled - and incredulous.

There's just something about the design of the 460 that makes it thirsty.  I don't know what it is, but it doesn't endear me to that engine.  Maybe the Scotty-built engine will at least put a smile on my face - as I fill up with gas frequently?

[grumpin]

In my 1994 F250 I used to have with the EFI 460, the best I ever saw was right at 13 MPG.

It did have 4.10 gearing though.

Better than my 1986, but the 86 fun factor is higher.

If we had a bad winter, i.e. driving around town slow and in 4WD, I would get about 6 MPG. I haven't checked the 86 in that type of driving, didn’t want to know. My estimate is between absolutely horrible and terrible!