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Swapping a 3.5L EcoBoost V6 into a 2012 Mustang!

60K views 103 replies 34 participants last post by  rowekmr 
#1 · (Edited)
I had a bit of a change of heart with my build (hence the new build thread), so now I'm trying to swap a 3.5L Ecoboost V6 from an F150 into my 2012 Mustang! Why? Because I can, and I want to. I don't expect it to be cost effective. I don't care about resale value. I'm not trying to build an all out race car. Needless to say, please don't post how stupid an idea this is or trying to convince me to do something else. I'll be using a Ford Racing Control Pack to simplify getting it running. My swap will likely remain very street oriented. This is (or rather will be) my daily driver, and I'm perfectly happy to make compromises to keep the car extremely streetable and comfortable. I don't care if it's loud or rides a bit harsh, I just want it to drive and feel like a typical bolt on car. This means no roll cage, seat deletes, fancy tires that can't handle hurricane season, NOS, insulation removal, or anything of that nature.

Now for a few FAQs:

How much will it cost? A lot. Truth be told I'm not really sure but I'll let you know when I know. I'm expecting to spend at least 7k. (Edit: Well 7k didn't get me too far... 10-15k is more like it)

How much power will it make? A healthy amount. Again, I can't say for sure, no vehicle with this exact powertrain has ever been up on a dyno. I'm expecting around 450+ whp after tuning when the initial project is done. (Edit: we achieved 435whp with a conservative tune on 93 octane with a 250cc water/meth spray at 8psi for safety) I plan to take it over 500whp at some point in the future, but honestly, anything more than 600 just seems excessive lol.

How fast will it go? Don't know, don't care. I have no interest in running faster than 11.5 in the 1/4 and that is probably an attainable figure with the right tires. Ideally I would like to run high 11s on street tires (but that isn't really the main goal, low 12s will be fine with me).

How hard is the swap? I would say it is around medium difficulty. Stock 3.7 trans and motor mounts will work and stock accessories will bolt up, but that's about it. It needs a new ECU, fuel system, a lot of electrical work, and a lot of custom plumbing. The most difficult part is getting all of the original features you want to retain (AC, EPAS, gauges, etc.) working.

The Car:
Around May of last year I picked up an Ingot Silver 2012 V6 with a manual trans with around 40k miles on the clock. My other car (basically a modified WRX) had turned into a less than reliable, if still pretty fun money pit. The Mustang was supposed to be a mostly stock daily ...yeah right. It didn't take long for the first mods to start and you can probably imagine where it ended up. This was my build thread before I decided on a swap:
http://www.allfordmustangs.com/foru...72361-gator3-7s-build-thread.html#post7691673






The Engine:
I picked up a 2014 3.5L EcoBoost V6 on eBay for a steal. It only has 34k miles on it and came with literally everything, from turbos to accessories. I won't need all of it obviously but it's nice to have and I can sell what I don't need.



What's done so far:
As of right now, the car has everything BMR makes for the rear suspension, a Dynotech 4" aluminum driveshaft, Blowfish shifter support/safety loop, Koni STR.Ts with BMR street springs, and a few other things.






Right now I'm working on getting the 3.7 out and putting the 3.5 in. Unfortunately I have a strong feeling this is going to be the easiest step lol. I have ordered the clutch and flywheel that will be going on the 3.5 and the 3.7 is just about ready to come out. Once everything gets here and I have a free weekend, I'll go ahead and make the switch. I'm also in the process of moving the battery to the trunk and finishing up the suspension. I'll be doing YouTube videos as I go along as well. The first one could be better, but it's not too bad at explaining what's going on with the car right now:





There's still lots to do, but I'm excited to get this swap going!
 
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#2 ·
I like it! Keep us posted. This is modification! I'm getting bored with the constant bombardment of questions about "what exhaust system I should get?"

Pete
 
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#4 ·
This is very interesting. Sub`d
 
#5 ·
Thanks guys!

I believe Ford Racing makes a control pack for every EFI crate engine they sell. The only 2 that arent V8s are the 2.0L I4 EcoBoost and the 3.5L V6 EcoBoost. I don't think they released the 3.5 EcoBoost crate engine and control pack until a bit earlier this year though, so it's still a pretty recent thing. I should be the first person to ever put this motor in an S197 using the control pack, so that's pretty cool. It should be a very unique car, and that's a big part of what attracts me to this swap.
 
#6 ·
I was just wondering if the 2.7eb or the 3.5eb will end up as the mid level Mustang engine in the future.


Good luck, I have followed a thread where a guy put a 2.7eb into a 66 F100, he has been on it for over a year. Very interesting and very expensive.
 
#7 ·
Gator, you never cease to amaze me! Sub'd...I love threads like this. I hope it comes to fruition.

What did you do with the Turbo you bought? I'm assuming you sold it to fund this?!
 
#9 ·
Thanks!

I actually still have that turbo and the kit for it but I'm trying to sell it right now. It would really help in getting the rest of the money to finish this project. So far I've just sold my old 3.7 mods and one of my bikes to pay for this but I'm out of money again lol. I won't have too much time to get it finished until May though so I'm not in a big rush.

I've actually been hoping that the 2.7EB makes it into the next Mustang lineup haha. I like the 2.3, but it just isn't quite quick enough from the factory. I don't think we'll be seeing the 3.5EB in a Mustang too soon though, unless one of them (probably the coyote) moves up market. They're just too close to each other right now for it to make business sense.
 
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#11 ·
There actually is a 3.5EB swapped Fox out there now, I think he just finished it up a few weeks ago.

The block itself is basically the same (smaller bore) but that's basically it. The heads are completely different (mostly to allow for direct injection), and the rotating assembly is stronger. The stock internals in the 3.7 are good for roughly 500whp, while the stock internals in the 3.5 really haven't been pushed far enough by enough people to know what the limit really is. One of the most reputable tuners for this motor guesses the limit is around 750hp with a good tune, and there are a few currently out there with over 600whp, so far very reliably.

In theory you could kind of "Frankenstein" together a 3.5EB/3.7 hybrid but it's really not worth the trouble and cost. It would be better to either A) get a custom turbo setup for the 3.7 and a built motor (which are very cheap by the way) or B) swap out the whole motor if you're a bit crazy like I am lol
 
#14 ·
I've been pretty happy with the blowfish shifter support in keeping my shifter aligned so far, but I actually just pulled the trigger on some BMR engine mounts last night. Not only should this help with the shifting as you mention, but it will also give me some adjustment in engine height that will be very helpful in getting the turbos and exhaust pipes to fit just right with the steering shaft and firewall.
 
#17 ·
motor mounts....mine were also adjustable, but with the 3.7 the oil pan would come close to the K member so I didn't drop mine.

apples/oranges I know but easy to look at before something bad happens. I was amazed at how it improved my shifting. I ended up with an older MGW but this was the biggest improvement for "blocking" that I did.
 
#19 ·
I think the 3.5EB oil pan is nearly identical in dimensions to the 3.7 oil pan so I may still have this issue. Hopefully I'll find out this weekend. But that's why I got adjustable ones, worst case scenario, I just have to go back to stock height.
 
#20 ·
How much power will it make? A healthy amount. Again, I can't say for sure, no vehicle with this exact powertrain has ever been up on a dyno. I'm expecting around 450+ whp when the initial project is done. I plan to take it well over 500whp in the future, but honestly, anything more than 600 just seems excessive lol.


!
How are you getting that much power out of that engine? Bigger turbo? Are you worried about long term engine life if you have a bigger turbo?
I don't know much about engine swaps or the 3.5L ecoboost so I'm hoping you can educate me
 
#21 ·
I know nothing about the EB engines either Are the internals forged or cast?


305hp out of 3.7 / 226ci engine is 1.35hp per ci.


380hp out of 3.5 / 213ci engine is 1.78hp per ci.


I don't see any more out of cast internals.
 
#22 ·
I too am very interested in this project but wonder how you expect to get 450+ HP at the wheels when the engine is rated 365 HP at the crank. Are you adding additional engine mods during the initial install phase? If so, what do you have in mind?

Very innovative project... I hope it goes smoothly. :cheers
 
#23 ·
Thanks guys!

One of the biggest reasons I'm swapping is because the 3.5 EcoBoost is an extremely strong motor. I believe the crank is actually identical to the one in the Ford GT race car, and it has forged rods. It does have hypereutectic pistons, but it's been proven reliable at extremely high power levels. MPT is getting well over 600whp in their F150 with upgraded stock location turbos and a small shot of nitrous, but nobody has actually been able to find the limit of the F150 EcoBoost yet. Some very well respected tuners have estimated that it should hold 750hp reliably with a good tune. The direct injection works wonders at preventing predetonation, which is how they were able to squeeze 365hp out of a high compression, boosted motor on 87 octane. As a result though, they are extremely responsive to tuning, especially using higher octane fuels and added boost, without loosing much of the reliability.

Being a turbocharged motor, adding more power is a very easy process. The boost pressure is controlled by the PCM through a boost control solenoid, so raising the boost level is as simple as a remap. A tune *alone* can add around 100hp to this motor. Assuming a roughly 12% drivetrain loss in the Mustang, that would put me over 400whp with just a tune. But the F150 has several restrictions that I won't have. The F150 has 2.5" downpipes that lead into a single exit 2.5" exhaust. My setup will likely have 3" dual exhaust all the way back, and lets just say I don't have to worry about emissions checks in FL... In addition I'll be using an upgraded intercooler. I'm going to try to do as much as I can to it during the install process, but I won't be able to do too much until I can afford new turbos (well over 2k) and new injectors (also 2k). That said, those two upgrades should get me 600whp on stock bottom end and I don't think I need any more than that. The 450+ whp estimate is actually not mine, there's one other guy in Colorado that just finished this swap (not dynoed yet, but I'll let you know) and he's the one who made the estimate. I was skeptical at first, but he really knows his stuff and after doing a bit of research, 450whp does seem possible.
 
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#24 ·
From the MPT website:

"So you could imagine how excited we were when our Stage 1 93 Performance Race tune laid down a consistent 382 horsepower and 463 ft-lbs of torque at the wheels while heat soaked. The boost curve was solid with 19-20 psi peak and a slow taper down to our redline boost target. We gained a solid 100 horsepower and almost 140 ft-lbs of torque with consistent gains throughout the entire RPM range."

This is on an otherwise bone stock truck with about 20% drivetrain loss. The manual transmission Mustang should be closer to the 12-14% range (hopefully closer to 12). Stock boost is about 12psi, so 20 is a healthy increase. Add in a full "off-road" exhaust and an upgraded intercooler and it should be a potent combo!

Possibly even more exciting than this is that they ran a 13.8 with that truck! Considering the fact that the truck weighs nearly 2000 pounds more than my Mustang, I'm excited to see what this thing can do!
 
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#25 ·
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