Duratec Port Head Swap

[Troubled81]

Well i have been thinking long and hard about what to with my built bottom end speed6.

I melted an exhaust valve and damaged my ported head over a year ago trying to get the best gas mileage out of it and it has been sitting in the garage collecting dust since.

The new head i got had a damaged cam so i will be going through the PITA process of setting the valve lash now as well as porting the head. Since everything is apart and i have to lash i thought about getting cams and I also asked about upgraded injectors back then and all the people making them said sorry no.

this has got me thinking very hard about the DI setup in our cars and how limiting that can be. A switch to port injection head and stand alone ecu would raise the tuning and power ceiling pretty high.
-Injectors are cheap
-There are a lot of duratec cams
-The duratec heads are not swirl heads so they flow way better and are everywhere (well over 300cfm ported on a 2.5L which is in escape and fusion)
-intake manifold options are plentiful, some cheap, some $$$.. (ebay Cosworth anyone?)

So has anyone here looked at what would be required to swap a 2.3-2.5 head on our cars?

From what i can tell the stand alone would need an extra output to run the rear diff solenoid on speed6’s, but that should be it and then we can all a cool digital dash.

I also thought about getting the new holley DI ecu but then we are still limited by the stock injectors so in a max effort build does it make sense to carry the weight and complexity of a fuel system that needs help over 450hp and requires a head with 4 restricted ports.

What do you guys think?
Has anyone looked into it or done it?
I searched the forum and found nothing.
Thanks,

 

[Easter Bunny]

Have you priced a standalone? Most people stick with the mzr head and ECU and add port injection in the intake manifold

 

[Troubled81]

Holley is 990 for the basic setup and 1200.00 for drive by wire and they both have closed loop wot fuel.

It is not a lot more then buying a cobb, and the university to get full access or a paying a tuner. I can sell my versa tune license, my cobb and basically pay for most of it.

Moving forward we would not need to buy the hpfp upgrade, the injector seals, deal with the sensors, relief valves etc. I am just asking if anyone has looked into it? We spend so much to squeeze everything out of the DI system and maybe that money would get us further safer with a holley stand alone and an escape head with some cams and an ebay intake.

I am going to track down a head, but I don’t think that there will be an issue bolting it on. I will keep you guys in the loop.

 

[Easter Bunny]

It would be easier to get head gaskets and compare

 

[Awafrican]

Sounds like a cool project, you may be the first to try, I can't recall if @Enki looked into it or not.

 

[Troubled81]

So more digging and i have found out that it is very common for MS3/6 people to swap the 2.5L bottom end into their cars. This means the deck faces are the same.

I found out the timing covers are different, but interchangeable, so that is cool and makes for one less thing to worry about.

The cam rings are the same, and the vvt solenoid is different, but you can swap the mazda one in.

So it seems like this is more and more a viable path for people that want to make a max effort MS3/6. I will keep everyone updated.

 

[Devinthedood]

Tuning in for updates with interest. Those other guys get to have fun with their franken-engines, why not us?

 

[StreetSpeed6]

I too have wondered how amazing a speed 6 could be running regular injection and not limited by factory di. I understand guys just go pi instead but seems much more simple only tuning for 4 injectors and those injectors flowing enough fuel for our higher hp goals. Bigger itfp and big cc injectors and voila! Lol Maybe im dreaming but wish someone would just make bigger di injectors for our platform

 

[SharksInSpace]

This does not seem like a truly cost-effective alternative to me, but I'm in for the adventure and am genuinely curious how it works out. Would be really neat to see made happen if only for the sake of ingenuity and experimentation.

 

[Troubled81]

So i picked up a 2.5l head and intake at the junkyard for 185.00 canadian and have been doing more research at the same time. Attached are the stock intake manifolds and the bowl worked ms6 head vs stock 2.5l. I have to say there is no contest here on the heads. The 2.5l is a much better design for all out power. The ports bowls are way better and the cross section is larger.

The attached dyno sheet is for a nc miata whp with a 2.5l swap stock intake manifold big header and fab9 cams on a stock head. I would expect the peak power to get pushed a little higher due to the smaller displacement and loose a bit due to the turbo manifold but i am very excited for 200+ na hp as point to start adding boost. The cams are 599.00 and they come with the shims to setup the lash.

As for the ecu and awd. I have been price comparing all the ecu’s and figured out that the AEM infinity looks to be the best option for me. It has built is drive by wire and wideband control megasquirt does not do DBW and i would have to buy a wideband controller. The few hundred dolars saved would be eaten by fixing that cost. I have reached out to them about the awd solenoid control as that is the last big question mark.

 

[Tomas]

So more digging and i have found out that it is very common for MS3/6 people to swap the 2.5L bottom end into their cars. This means the deck faces are the same.

I found out the timing covers are different, but interchangeable, so that is cool and makes for one less thing to worry about.

The cam rings are the same, and the vvt solenoid is different, but you can swap the mazda one in.

So it seems like this is more and more a viable path for people that want to make a max effort MS3/6. I will keep everyone updated.

Where did you find this information that 2.5L botton ends are "very common" swaps for MS3/6 owners? I can assure you they are not. The mazdaspeedforums site is down but there was a guy there going by the name "Roadblock" who tried the conversion you are attempting and was not succesfull. IRRC the bolt patern of the cylinder head bolts did not match up or the oil channels. Something like that.

I hope you are successful. Simply because it would be cool if you are. But as Easter Bunny said going PI as a piggy back to the OEM ECU set up with DI is not only simpler but a proven solution. You will not be limited by fueling this way either. Simply use larger PI injectors as you would on a PI engine and leave the DI system to cool the top of the pistons and increase the knock resistance of the motor. The limiting factor once you hit about 800 lbs of torque will be 4th gear will spread apart from the layshaft and cause your tranny to kaboom if you really want to go that far. on the MS6 you will also probably experience transfer case failures at that torque level.

 

[SharksInSpace]

2.5 bottom end swap is getting more common for the Facebook Poors who blow their shit up being stupid and then can't afford an MZR block.

 

[Tomas]

Aha. So the 2.5L bottom ends match up exactly to the DI head? Guess I need to spend more time on facebook and less on gay porn.
Do they have piston cooling jets? Are the cranks the same? forged or cast?

 

[Troubled81]

Thomas,

as SharksInSpace wrote there are a number of guys pushing 350-400hp on the stock bottom end. There is a video on youtube comparing a disi to a 2.5l. I really don’t care about stock parts here.

This experiment is not for helping people that are chasing 400whp (although that is all my turbo is good for). This is about helping the people going for 700+whp. I have the talent and skills to build this, I have been part of this group for 8 years, i love my 11sec ms6 and would like to see more then a handful of 10sec ms6 out there, maybe even an 8sec one!

This 2.5l head flows way better then ours and a rip off of the Cosworth intake can be bought for 250.00 on ebay! Cams are 600.00 vs 900 and there are way more options because the nc miata people are all swapping this engine into their cars.

As for the comment about a port injection split second setup that piggy backs off your cobb tuned/versa tuned disi system that you try to get them to all dance together being easier then an aem with a single system with auto tune, i am not so sure about that.

The AEM also has far better logging system, ability to control and tune the awd, built in meth control, anti-lag, 2step, wot box, traction control, the list goes on and on. Any shop will be able to tune the car now if you get stuck!

Esslinger engineering sells a 2.7l stroker kit for the duratec and if we can run port injection they have base maps for it already. Imagine if someone took that motor dropped the compression and put a big turbo on it! It makes over 320hp na!

I also priced compared it out and it would be about 6000.00-6500.00 for a fully built ported head (HPFP, injector seals, cleaned injectors, valve springs), port secondary injection intake with 1000cc injectors with controller and fuel system on a disi setup.

The same thing with an AEM with a built 2.5l head (inconel exhaust valves, ti valve springs, ebay intake manifold, regulator, hoses and fitting) and 1650cc injectors harness will be about 4000.00 and the AEM has all other befits listed above to sweeten the deal. The 2.5l head does not need porting as stock it flows 260+cfm but there are ported ones flowing way over 325cfm!

so if anyone wants my disi stuff it will all be going up for sale, as will my v2 cobb and i guess I can’t sell my versatune.... I need to get this car together and to some no-prep races next year to prove this out and get people talking about the ms3 and ms6 again

 

[Troubled81]

Oh, AEM got back to me and if the awd solenoid is controlled by a solid state relay (what is in our awd module) it is not a problem at all. I will have to make the tables from scratch so there will be a learning curve there but i will happily share that with everyone and now we will be able to tune it to suit our needs!

 

[Tomas]

I hope you can finalize your project but I think you are underestimating the amount of work involved.

 

[Troubled81]

If you think this is a big project the other car i am building is a 51 hudson i am converting to electric. This is a lot easier.

 

[alexwlwsn]

I'm hoping this pans out! A PI-only MS6 could be pretty unique and cool in this world of cookie-cutter Mazdaspeed builds.

 

[JohnnyTightlips]

Excited to see how this progresses. How do you plan to control the HVAC , Wipers, Gauges etc? Will the OEM ECU still be handling some of that? Are you planning to use the 2.5 bottom end? I don't know if that has been proven to support the same amount of power as the MZR. With the power you are looking at you will likely need to go with sleeves in the block so that could negate the need for the MZR bottom end. Good Luck with this always nice to see something new and some experimentation.

 

[Troubled81]

Excited to see how this progresses. How do you plan to control the HVAC , Wipers, Gauges etc? Will the OEM ECU still be handling some of that? Are you planning to use the 2.5 bottom end? I don't know if that has been proven to support the same amount of power as the MZR. With the power you are looking at you will likely need to go with sleeves in the block so that could negate the need for the MZR bottom end. Good Luck with this always nice to see something new and some experimentation.

Thank you, I have a build 2.3l bottom end already (that i built 8 years ago maybe) that this head will go on. The factory engine ecu doesn’t control the inside of the car so i am not overly worried about that. If the body control module fights me I will leave the factory ecu will there just to shut it up (i am not smart enough to make a canbus emulation). For me i am not looking to get more then the corksport 18g can do (should be deep 11’s). This experiment is really just a because I can and want more fast builds and less part outs.

After i make it public want it take to do this I hope a company starts to make pnp harness. I will post the baseline tune files wiring diagrams and this build thread to help.