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Turbo MZR RX7

I've disposed of essentially all of my 2.3 Lima/Folvo parts.  My RX7 now has an empty engine bay.  I'm not going into why I've chosen to do this just accept this is what I've done.

I told Paul that the plan is to take a Duratec/MZR (Mazda name) 2.5 from a 2016 Fusion, turbocharge it, mate it with an NC Miata transmission and stuff that into the RX7.  We'll see if the plan comes to fruition.  Paul suggested I start a build thread here as members might find it of interest.

So, I've acquired the following:
1. 9000 mile 2.5 engine from a 2016 Fusion  (175 hp @6000 rpm NA)
2. NC Miata inner and outer intake manifolds
3. NC Miata engine mounts
4. NC Miata flywheel and clutch
5. NC Miata 5 speed transmission (I like the gear ratios better than the ones in the 6 speed although internet lore says the 6 speed is stronger)
6. After market T3 cast iron turbo manifold
7. 2006 Ranger 2.3 oil pan
8. 2006 Ranger 2.3 water outlet
9. 1996 3.8 Mustang throttle body (Miata uses drive by wire)

And last, but not least, I have my 1989 RX7 GTUs.  This car has a large intercooler in the nose, factory 4.3 ratio LSD, 4 pot brake calipers, and the large (for an RX7) factory basket weave 16" wheels which have been freshly powder coated.

I've done a test fit and it looks like it will all go together after a significant amount of massaging of parts.

Here are the challenges:
1. The 2.5 is VVT.  I need an ECU that supports that.  Probably going to be a Stinger Pimp XS
2. The 2.5 block has to be drilled for oil supply and return from turbo
3. Mazdaspeed people are using the bottom end of the 2.5 as a bolt in replacement for the Speed short blocks.  It seems to work but there seems to be a top limit of about 375 hp before "bad" things happen.  I'm going to be shooting for about 300 hp on this.
4. I have severe reservations the Miata clutch will take this.
5. I'll have to have a driveshaft custom built.
6. Driving the water pump without an AC compressor on the engine will be a difficult due to direction of rotation.
7. The 2.5 is a returnless system where the ECU conrols fuel pressure.  I'll have to modify that to a return system.  Aftermarket parts are available to do this.
8. The water return from the back of the head causes significant packaging issues
9. Both the Ranger and the MIata did not use the balance shaft weights that are present in the 2.5 (and 2.3 Mazdaspeeds).  I want to retain the balance weight but I'm not sure they will clear the Ranger pan
10. The transmission crossmember looks to be difficult
11. The Miata engine mounts work extremely well. The driver side bolts in.  The passenger side had to be shortened and a spacer made,
12. The RX7 is limited on hood clearance.  I dropped the engine crossmember 1/2" on the Folvo build to help with that.  I think that will give enough room for the MZR (I'm a Mazda guy- I can't call this by the Ford name) also.

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Sounds like fun, Don......I'm jealous!! Is the acquired Duratec/Fusion 2.5 essentially the same as the Ranger 2.3 that reportedly weighs less than 300lbs soaking wet?? I've "heard" in the past that either the crank &/or main caps/webbing on those motors have a tendency to disassemble itself/themselves at boost levels past, say, 8-15psi ~ OR......have they since strengthened 'em? [Image: confused0024.gif]
Placerville, California
(former)  2.3T '78 Courier ~ (current)  2.3T '87 Ranger & '82 Mazda B2200 (smog-exempt diseasel truck)

I can supply you with a Miata clutch that can handle up to 500 lb/ft. street versions can hold 320-400 lb/ft. Stock one only supports 225 lb/ft or so.
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Wicked project!

I am not sure if this would apply, but, when I worked at Mazda a boat load of Speed 3s, 6s, and turbos CX- SUVs, all starting coming in with stretched timing chains smacking the timing cover. I would definitely look into getting the beefed up chain!

I worked at Mazda between 2011 and '14, if they didn't have it figured out then, I would bet it is safe to assume you should do the chain, especially if you're blowing on it!


and the lawsuit:
88 TC in Canyon Red
Walbro 255, AEM wideband, CP Pistons, FMIC, PIMP, SVO T3, Ranger roller, 3" Stinger exhaust, AFPR, RFL BOV, Gutted upper, Ported lower

I've owned a Speed6 since 2007 and am aware of the timing chain issues.  I've replaced several.  This is one reason why I'm doing a 2016 engine.  Ford did do a beefed up timing chain on the later 2.5's.

And here is a view of the turbo side.  Disregard the junk T3.

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A few more pictures

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Time for a bit of an update:
Drive Shaft- 29.5" is too long. I had a 28" Fast Shaft from an MGB project that is the correct length.

Engine Location- The Ranger water tube is about 1/4" from the firewall. That's as far back as it will go without modifying the firewall. It's not as far back as I'd like. The front cover is essentially directly over the center of the steering rack. That sets engine height.

Engine height- I'm glad I lowered the crossmember by 1/2". It's tight. The VVT actuator is about 1/8" below some crossribs in the hood. The oil fill and the dipstick handle prevent the hood from closing though. Both of these can be shortened with a bit of work though.

Engine mounts- While the mounts go into the holes in the chassis they don't line up well and are about 1.5" short. I'll be welding some square tubing on the steel portion of the mount to correct that.

Shifter location- The center of the shifter is at the forward edge of the opening. It has to move back roughly 2.5" to be in the center of the opening. I cut the shifter handle about an inch above the ball and tapped both the ball end and the handle end for an M8 screw. I then made a plate to move the handle back to center of the opening. I'll probably weld this up later.

The turbo clears the firewall. I have room to run an internal 2.5" V-band wastegate. I'm welding a 2.5" 90 degree elbow to the V-band flange to point straight down. Then a 2.5" to 3" bell to a 3" down pipe.

Intake- The Miata intake with the Mustang 3.8 throttle body look like they will work well. The throttle cable reaches but I need to fabricate a bracket for the cable

Transmission mount- This going to be tough. The PPF adds a lot of depth to the tailshaft. I'm not sure what I will do here.

Cooling- It looks like I will need to add in-line ECT and probably tap a boss on the Ranger coolant outlet for the temperature gage. There will be a mess of coolant lines. I think I can use a factory NC Miata lower radiator hose.

I'll add some pictures over the course of the day. This is going to be a bit ugly as I'm using various couplers in different colors I happen to have on the shelf. Once I get everything located I'll buy some matching silicone couplers.

More Pics

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Looks like wastegate/dump tube clearance is going to be tricky with that large coolant (?) port near the firewall. Does the exhaust pattern allow the manifold to be flipped over?
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