Day dreaming about a 4.0L in a Scorpio

[brokencase]

Now.. The 4.0 Intake manifold parts..

Lower..

40_lower.jpg (272.52 KiB) Viewed 3629 times

Upper..

40_upper.jpg (234.94 KiB) Viewed 3629 times

The way the upper hooks around I think it must sit taller than the Scorpio manifold.

The 4.0 intake ports on the manifold are "inline" whereas the 2.9 has them "on each side"

I would take the 4.0 manifold and cut the top off. I would then bolt on a large rectangular square aluminum plenum tube to the 4.0L cut off bottom.

Then I would weld on to the plenum a turn and then merge to a plate to mount the Scorpio throttle body.

The result would be a manifold that looks and sits the same height as the original Scorpio manifold.
Naturally you would have to weld on whatever studs are needed to support the linkage and whatever other stuff.

[brokencase]

Another thing I am not so sure about.. There is a distributor hole for the 4.0L cam position sensor. The hole and gear are the same as for the distributor. But if I stick a 2.9L distributor in that hole - will the upper part of the distributor interfere with the 4.0 intake manifold?

[brokencase]

There is an oil pan problem as well... Don't think the 4.0 oil pan will clear the front crossmember.

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[brokencase]

You might get the 2.9L oil pan to fit the 4.0L. There are some subtle differences in the holes as I have indicated in RED.
Maybe you can drill new holes in the 2.9l pan to get it to work

However how the pan fits to the front cover could still be an issue.

2.9L

29bottompanissue.jpg (66.76 KiB) Viewed 3617 times

4.0L

40bottompanissue.jpg (64.04 KiB) Viewed 3617 times

[brokencase]

Also - be advised that the Scorpio 2.9L oil pan is different than Ranger 2.9L oil pan. You need to fit the Scorpio pan.

[DPDISXR4Ti]

There is an oil pan problem as well... Don't think the 4.0 oil pan will clear the front crossmember.

That pan looks very similar to the one used on the '91 - '94 2.3 Ranger. It look some milling, grinding, and minor re-fab of the X-member, but I've had one in my XR for years now. A side-by-side comparison of the two pans would tell the story much more definitively.

I'll address some of your other points separately, but first, a general comment/link. As you might imagine, the 2.9 to 4.0 swap is very popular with the Ranger / Bronco II crowd, given the millions of vehicles produced over a span of decades. As such, there is a lot of info on the swap. Here's one index link with multiple pages under the "Engine" heading....
https://www.therangerstation.com/tech_l ... ions.shtml

We add issues with the Scorpio and the way it varied from the Ranger 2.9, so nothing will be as easy as described there, but the challenges are not insurmountable. It does seem like in general the preference is to stay with the early (EEC-IV) 4L donors. Here's one thread where someone does exactly that...
https://www.therangerstation.com/forums ... ld.150049/

[DPDISXR4Ti]

Another thing I am not so sure about.. There is a distributor hole for the 4.0L cam position sensor. The hole and gear are the same as for the distributor. But if I stick a 2.9L distributor in that hole - will the upper part of the distributor interfere with the 4.0 intake manifold?

Here's a 10-page thread on exactly that question!
https://www.therangerstation.com/forums ... 97/page-10

But don't bother reading it - the question is still not answered as nobody has actually tried to do it! The one issue that was brought up is whether the deck-height difference between the 2.9 and 4.0 blocks could be an issue.

If there's a minor interference conflict with the intake manifold, perhaps that could be addressed during the fabrication of the hybrid Ranger 4.0 / Scorpio 2.9 intake manifold.

[brokencase]

Don't get me wrong, I'm with you on the daydreaming, just trying to provide info regarding the hurdles as I have identified them.

The difficulties of installing the 4.0L in the Scorpio are comparable to the Taurus SHO swap.

Potential paths to more Scorpio power...without changing the transmission:

4.0 OHV swap:
1) Oil pan issue - possible to use Scorpio pan on 4.0L
2) Driver side motor mount bracketry required.
3) Engine management - Must Fab New manifold
a) Adapt Scorpio Throttle body and run Scorpio ECM - Assume ECM can manage it (Scorpio has 14lb injectors but 4.0 will have 19lb injectors)
b) Adapt 4.0L throttle body and bring over entire engine harness ECM etc.. Difficult
4) Possible distributor issue if you go with Scorpio ECM.
5) Exhaust - You will probably have to use 4.0L headers and you will most likely have to modify them to fit.
6) Mounting accessories will probably not be too much of a problem.


SHO swap..
1) Oil pan issue - Must cut/weld SHO pan
2) Flip intake manifold 180 degrees.
2) Both motor mounts must be engineered.
3) Engine management - Must get ECM and engine harness from donor SHO. ECM wire diagrams available for both vehicles. Some pin swapping on Scorpio ECM plug and wire in SHO injector harness - Difficult
4) Must acquire Vulcan A4LD bellhousing and must get an automatic flexplate for SHO - re-drill for Scorpio torque converter.
5) Exhaust - CNC header flanges available for SHO but you have to weld up the rest. You might be able to cut the flanges off of 4.0L headers then bend/adapt/splice to SHO flanges.
6) SHO a/c compressor same as Scorpio's and is in about the same position.

The 3.5L stroker option..
1) Buy 4.0L crankshaft from RockAuto.
2) Grind crank and block to make crank swing. Send crank and rods out to get balanced. (BTW - who around you does that these days?)
3) Purchase Chrysler 3.7L pistons. A little bit of honing of wrist pins may be needed.
4) cc the heads and check piston clearances, etc.. Figure our compression ratio, should end up around 10 : 1
5) Install 16lb injectors.
6) Install headers..
7) You are running premium now.. Horse power? Somewhere around 165 but torque slightly less the 4.0L.

The 4.0L swap and the 3.5L stroker have the advantage that the State inspection mechanic will give you no problems. He won't know any better.
But in my state they will not like it if I put an SHO motor in my Scorpio. Unless I first convert it to classic or antique tags - and I have to do that before I do the swap...and even then it is not entirely kosher.

[brokencase]

Here is a shot of the Scorpio oil pan BTW.. See how it is flat and close to block for the front half?

scorpiopan.jpg (22.65 KiB) Viewed 3605 times

[brokencase]

It is a little bit of a disappointment that for all the vehicles that the 4.0L OHV went into that there were no variations in the intake manifolds.
I am pretty certain the Aerostar is the same as the rest because my brother had one.

[DPDISXR4Ti]

Here is a shot of the Scorpio oil pan BTW.. See how it is flat and close to block for the front half?
scorpiopan.jpg

The front portion does seem even shallower than the 2.3 pan. I wonder if that's because the Cologne V6 sits a bit lower than the 2.3?

For reference, here's a shot of the early-90's Ranger/Mustang 2.3 oil pan which I currently run. You can see how it's got a profile similar to the 4.0 pan.

ALumPan-2.JPG (986.05 KiB) Viewed 3593 times

[DPDISXR4Ti]

It is a little bit of a disappointment that for all the vehicles that the 4.0L OHV went into that there were no variations in the intake manifolds.
I am pretty certain the Aerostar is the same as the rest because my brother had one.

Yes, unlike the 5.0 where there's a large pool of different configurations to draw from with a variety of intakes, brackets, etc.

[DPDISXR4Ti]

So here's a Cologne 4.0 OHV out of an Explorer fitted with a couple turbos and dropped into a Mk2 Granada...
https://engineswapdepot.com/?p=65461

A bunch more pics on their Facebook page here...
https://www.facebook.com/media/set/?van ... 2562490441

Lots of good pics including this one of the re-profiled oil pan...

[brokencase]

More details regarding the stroked 3.5L option...

https://passionford.com/forum/technical ... roker.html

"I had to deck my block approx 0.032-0.035" to have the pistons flush with top of block." <---not sure this is the case with the 2.9L, he is talking about the 2.8L

and..

"I used Jeep 4.7 V8 pistons in mine. They are the same as the 3.7 V6 piston but for some reason they are cheaper, plus the extra 2 pistons are good for using for dummy builds when clearancing the block, and believe me you'll be doing plenty of that."

and..

"The crank needs counterweights machining down, I think it is about 0.500", can't remember exactly as it was done quite some time ago. "

and...

"The biggest problem is getting the compression ratio down to an acceptable level, there's not a lot of meat on the crown of these pistons. So I had a small bowl machined into mine, plus I opened up the combustion chamber."


Little more info here..
http://www.capripower.co.uk/forum/index ... ost-370430

"Also looks like they have internally balanced the crank, I externally balanced mine which was a cheaper option.
Looks like it's going to be a real beast of a motor alright.
The torque these stroker motors make over a standard 2.8 or 2.9 truly makes it worth the effort."'

[DPDISXR4Ti]

More details regarding the stroked 3.5L option...
https://passionford.com/forum/technical ... roker.html

I don't think I'd want to go that route. My preference would be something that stays close to stock, just stock 4L in this case, and thus gets the roller cam and followers that come along for "free".

One thing I did see mentioned in that thread was the 6 vs. 8-bolt crank. Did all the 4L motors get the 8-bolt crank?

Raised the 4L swap on Facebook and Guy commented, who is friends with Phil and Noel and aware of the 4L swap done to Noel's Scorpio ~15 years ago.

It will fit , the intake is too tall, needs custom Intake and custom motor mounts and wiring help. Not just a bolt-in job.

I'm going to give Phil a call to discuss.