I'm not using a factory ECU, for better or worse. I'm...like...85% sure I can make it work. Might be a disaster though.

Also this is a 2018 engine, so it has dual injection, port and DI, so I don't run into HPFP limits.

 

You will make it work. I believe they still run into hpfp flow problems. I know for my next build with both injectors they still need it.
And aftermarket ecu will be sweet. I’ve been toying with syvec for a while now.
You will be able to get it tuned. I’m excited to see it done

 

Slew of design issues? The 230,000 mile stock 2.3 DISI in my daily driver Speed3 says otherwise Aside from the timing chain and the HPFP they're the same as the other MZRs. I think the big problems with the DISI are 1) not much factory oil capacity and 2) really bad factory tunes.

I do agree the 2.5 is a better motor. The timing chain is quite a bit beefier. The ring lands are just a bit on the weak side for boost.

The V6 Ecoboost swap is a cool one. I like it. Too heavy for my taste, and the 2.5 with an EFR7163 is providing more than enough power.

 

The swap is purely a vanity project. An LS would basically bolt right in if I wanted to write the check, but I've BTDT with a V8 swap and I want to try something different. The LFX seems to keep the light weight, but is just about already maxed out NA and adding more power means adding weight. A turbo 4 would be easier to fit up, lighter, and probably have the same/better powerband.

 

Snow- yeah the Speed's fuel system is very limited as well and most enthusiasts with 'big power goals' opt for AUX port fueling, meth or both. There's been some impressive numbers put down by the drag / street racing community if that's your thing but I'm in the minority of owners who track their cars.

Also, I've heard of many Focus owners experience a whole host of issues regarding the longevity of their RS engine (main joke was that they were built to grenade themselves right after the warranty expires, etc). How were these issues addressed in your built engine? Just curious


JinX- I do know that the 2nd gen Speed's had a couple minor redesigns which most people believe improved the common problems associated with the 1st gen and you're spot on that the timing chain is a very weak component. Imo, performing an EGR + balance-shaft 'delete' (with oil pan baffle) should help keep the engine healthy and have worked well on mine for years now with no issues. At one time I had planned to try and squeeze every last mile out of the original engine with all recommended services, etc but my tech said it wasn't worth the cost / labor and instead convinced me to drive the 2.3 into the ground and build a 2.5 on the side. Currently sitting at 105k and still running very strong. I'll let you know how long it lasts.


John V- 230k on the original engine??? I have never heard of such a thing and sir you have certainly earned your gold star if that is the case. From what I've seen over the years, they typically fail anywhere between 120-160k. I recently upgraded to an external oil cooler for a little extra juice; hopefully allows the engine to eek out a few more miles too.

And interesting to hear about your measurements on the 2.5. I've seen more than a few diy tubers types who've turbo'd their 2.5 with (what I'd consider) a certain level of 'success'. 'DRTuned Racing' out of BC currently offers 'custom boost tuning kits' for what appears to be nearly any mazda engine. Great option imo for people who love to tinker.

 

So the rs 2.3 engine issues seem to stem form incorrect oil.
It’s pretty heated but almost all the top builders believe that it’s not the car. Lots of guys were trying 5w50 oils that where not designed to the spec. I would be willing to bet most were caused by lspi which is a huge issues in that motor because the twin scroll was very effective in making power down low. What gets me is so many Mustang 2.3 which is basically the same engine can be tuned to higher than rs power levels and never have those same issues.
In fact many guys are running 360-380whp and have a significant amount of miles on them.
But as always nobody wants to admit they many have caused the issue by saving a few bucks on oil.
On my build they strengthened the back side of the block, and added a proper deck brace press fit then machined flat. They did they block mainly because I wanted the motor to be good for 800hp and run it at around 600. Which they have a lot doing the same with very good long term results.

Also I’m not sure the 2.7 ecoboost is all that heavy. Yes it’s turbos add weight but it’s still pretty light and for the size of the power band it’s gonna be thought to beat.

 

Oh and I think achieving 450whp using a franken 2.3 head / built 2.5 block won't be too difficult imo. There are many factors involved of course but the additional upgrades of a 3.5" (or 4" intake), large(r) TB, under pipe FMIC kit, Focus ST intake manifold adaptor kit, FullRace exhaust manifold (already using this) and appropriately sized large(r) turbo (per shop recommendation) should more than do it imo. But I suppose only time will tell

ps- I have considered storing a bunch of race gas at the shop or in my garage but I'm crazy. Def not for everyone, ha.

 

Well, I exaggerated. It's at 223,520 miles as of my drive to work today. Yes, original engine other than a timing chain replacement at 160k miles preventively.

I don't have the numbers in front of me right now, but I had a weight of the fully-dressed 2.7L ecoboost and it was around 200lbs heavier than my 2.5 in the same state of dress. It's a heavy engine.

In terms of 2.5L internals, I've had four of them through my shop. I've ruined the ring lands on one (my first one) and measured ring gaps on the other three. They were all at the tight end of the spec in the manual, something around 0.012-0.014". Way too tight for much boost at all. Especially for a hypereutectic piston. I am on forged pistons and rods with my current engine, with 0.022" / 0.019" ring gaps and it's seen up to 22psi on an EFR7163 with no problems. 2% leakdown across the board. I would not run a stock 2.5 with more than 7psi-ish boost.

 

I think it's just not really designed for your "average" non-car people, especially considering this engine was also put in the CX-7(the teardown channel I watch does say that CX-7 ones tend to fail more than the Mazdaspeed ones). Sure you can make it last, but it's not like a Honda or Toyota V6 engine at the time where there is a lot more room for error. You basically have to treat the timing chain like a timing belt, it seems like, and timing an MZR is a bit annoying due to the lack of a crank key.

And yeah the balance cartridge doesn't help matters. I have heard a theory that #3 cylinder lubrication is a bit sketchy because of it as well.

I mean, with a turbo 4, you would have to live with some lag. There has to be compromise somewhere.

But I agree that with GM V6, if you were to add force induction to it, then the weight will get pretty close to an NA aluminum V8.

 

The 2.7 with no turbos or accessories lands at about 360lbs, same as the aluminum 3.7 Mustang V6.

Complete with accessories, lightweight flywheel, turbos, and the Mustang MT82 (127lbs) I'm expecting about 550lbs. My 302/T5 combo in similar dress was also 550lbs. An aluminum LS and T56 is right around 600lbs.

I also quote engine weights with wiring, accessories, and transmission since you have to have those when you put it in the car. Sure, a 302 is heavier than an aluminum LS, but when you realize you can put a 75lb T5 behind the 302 instead of the 130lb T56 you need for the LS, all of a sudden you're 50lbs lighter.

 

So 180lbs heavier than the 2.5. My recollection was close. The issue with the V6 is you're dealing with two of everything. It's still a rad swap.

Oh, and I fixed the lag issue...

 

Glad you posted this. I always wondered how they compared to a ls. I know power wise which one I would choose. I’ve ran a bunch of times ls engines in a variety of cars and SUV’s. And not a single one was ever able to keep with my truck in the 1/4. Now of course displacement does matter but to get a ls to the same power level you also add weight. And of course you really kinda need to boost it to get the same wide power form low rpm all the way to make it fair.

 

Having a very built 2.3 and driven some well tuned 2.7 and mine being a 3.5. I can tell you that I don’t think you will ever get the levels or trq or ho you can get out of the 2.7. Plus the cost of building a 2.5 or 2.3 would be much more than the 2.7 stock with bolt ons and a tune. I actually bought my rs hoping it would be like the 3.5 and 2.7 and juts bolt on downpipe, and tune and make great power.

 

Sure, more displacement means more power. And Mikael and I have different goals for our cars. Mine is an autocross / track car that sees some street duty, and I think his is likely the opposite. Reducing weight on the front end was critical for me. 180-200lbs off the front end compared to an Ecoboost V6 is huge.

I will say that the 2.5 already makes more power than I can use up to about 80 MPH. So for a street car, more power would just be more work for the traction control.

 

Sorry i didn’t mean to come off that way. Yes your setup is good for what you were doing. Hence why I really wanted to be able to juts drop in a 2.3 ecoboost I have into one.
I’ve never driven one but always wondered if the guys who drop in an ls into one or a miata ever gained that much on the track. Especially some of the turbo or super charger miata’s. That weight has to make a big difference.

 

Nailed it.

 

JinX- You're correct about the BSD limiting oil to cyl #3 on the MZR. Lots of documentation on engines suffering from lack of lube.

John V- I'm pretty sure I've come across a vid or 2 of your 2.5 swap. Wild ride for sure! And I couldn't agree more with you on keeping the front end light as light as possible.

 

Could be, I think I'm the only one.