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Old 10-08-2015, 10:49 PM   #1
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Default Steering rack position, bump steer, etc

I'm researching swapping an Ecoboost 2.0 from a Focus ST into a NA Miata. I've heard everyone already say how dumb it is, so don't bother. I'm fairly committed. There was a guy on Miata.net who tried and gave up:

2.0L TGDI Ford Ecoboost engine swap - MX-5 Miata Forum

It looks like the issue of the injection pump on the rear of the head is fairly easily solved. After getting behind the dash, I should be able to build a pocket to house the pump without interfering with the HVAC system too much. That will allow me to bring the engine back what looks like approximately 3" from the position that the other guy has it sitting in. I would still need to lower it to clear the hood. This would necessitate moving the steering rack forward. This is my hangup.

Looking on the interwebs, there are folks (mostly drifting community) who use offset links on the end of the rack.

Voodoo 13 Offset Steering Rack Extenders Nissan 370z 09-14

The physics behind this concept are sound, however the implementation of it places an excessive amount of side load on the ends of the rack when you push the rack forward much at all. Another option would be a longer arm at the knuckle, but that causes issues with the ratio (it's a lever after all).


I'm just tossing some ideas out there. I might be able to gain the hood clearance I need with just the shift towards the rear with the engine. Besides, it's going to be a little while. I want the MT82 transmission from the new Ecoboost Mustang and I'm not finding any on car-part.com yet. From Ford, they're $2600 new plus $800 for the core, so new is out of the question.

I'm not looking to destroy the steering geometry and the general consensus is not to move the rack, although Boss Frog seems to do it. Has anyone here moved the rack and by how much? How much bump steer did you pick up in doing so?

Alright, done with the dumb questions for now...
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Old 10-09-2015, 12:48 AM   #2
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Is the ecoboost the same as the MZR?
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Old 10-09-2015, 03:38 AM   #3
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In some ways, yes. It's based off the Mazda "L" engine. The biggest difference is the head. It's a close cousin to the DISI engine in the Mazdaspeed 3. Because of the injection pump, packaging is a bit different. I think it would be an awesome swap though. I already have a 675 hp Coyote Mustang, so I really don't see the need to V8 swap the car. I want something with enough power to get out of its own way and still go around corners. The 1.8 is cool, but damn it, I want to be different. The engineer in me says it can be done, so I'm going to do it, even if I need to buy a Garage Vary Type 06 hood to do it. I'm just curious how far I can move the rack at this point.
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Old 10-09-2015, 01:51 PM   #4
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Don't move the rack. There are other options. BF is not where I would go to look for answers. There was a MZR powered NA at MRLS last weekend
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Old 10-09-2015, 04:50 PM   #5
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Not that it applies directly, but there are drop motor mounts for moving the MZR lower in the subframe on the NC cars for people doing the 2.5 swap because the 2.5 is taller than the 2.0. I don't know how or if that may be useful to you.

You may also look at various other oil pan configurations for that engine or look into building your own to reduce interference with the subframe and the steering.

The V8Roadsters tubular front subframe gives a lot more room around the engine than the stock subframe and may be the real easy button here. It comes in several variations for mounting different engines (V6 LFA, V8 LSX, no mounting points, or BP mounting points).
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Old 10-09-2015, 05:11 PM   #6
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Quote:
Originally Posted by sixshooter View Post
Not that it applies directly, but there are drop motor mounts for moving the MZR lower in the subframe on the NC cars for people doing the 2.5 swap because the 2.5 is taller than the 2.0. I don't know how or if that may be useful to you.

You may also look at various other oil pan configurations for that engine or look into building your own to reduce interference with the subframe and the steering.

The V8Roadsters tubular front subframe gives a lot more room around the engine than the stock subframe and may be the real easy button here. It comes in several variations for mounting different engines (V6 LFA, V8 LSX, no mounting points, or BP mounting points).
But it also lacks mounting points for an undertray/splitter so some further, albeit minor, fab is needed.
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Old 10-09-2015, 05:13 PM   #7
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Quote:
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Don't move the rack. There are other options. BF is not where I would go to look for answers. There was a MZR powered NA at MRLS last weekend
Do you know who it is? Do you know if there are pictures anywhere?
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Old 10-09-2015, 05:16 PM   #8
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Quote:
Originally Posted by sixshooter View Post
Not that it applies directly, but there are drop motor mounts for moving the MZR lower in the subframe on the NC cars for people doing the 2.5 swap because the 2.5 is taller than the 2.0. I don't know how or if that may be useful to you.

You may also look at various other oil pan configurations for that engine or look into building your own to reduce interference with the subframe and the steering.

The V8Roadsters tubular front subframe gives a lot more room around the engine than the stock subframe and may be the real easy button here. It comes in several variations for mounting different engines (V6 LFA, V8 LSX, no mounting points, or BP mounting points).
Yes, I plan on going this route or fabbing my own. It all depends on how ambitious I'm feeling. Again, the issue is getting it far enough behind the steering rack to lower it. The regular MZR seems to have less of a protrusion on the back of the head and it also doesn't have the high pressure injection pump mounted to the back.

As for the oil pan, the pan and tube for the Ecoboost Mustang is just about as low profile as possible in the oil pump area. It brings the pickup tube around the crank and counterbalance shafts and towards the back. Another option is the counterbalance delete kit and a NC Miata pan, but you're still dealing with the physical location of the oil pump, which at the bottom right corner while facing the damper. In the link above, the guy who tried this swap basically sat the oil pump on the input flange of the rack. In his location, it looks like if it came back just a few inches, it would clear the rack, but it would still sit too high for the hood to close. If I absolutely had to, I'm sure I could build a dry sump system, but that's an awful lot of work.

Last edited by cheeseclock; 10-09-2015 at 07:03 PM.
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Old 10-09-2015, 06:54 PM   #9
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Standard MZR:

<a href="http://s924.photobucket.com/user/Christopher_Bush/media/Mobile%20Uploads/MZR_1.jpg.html" target="_blank"><img src="http://i924.photobucket.com/albums/ad83/Christopher_Bush/Mobile%20Uploads/MZR_1.jpg" border="0" alt=" photo MZR_1.jpg"/></a>

Ecoboost:

<a href="http://s924.photobucket.com/user/Christopher_Bush/media/Mobile%20Uploads/stengine.jpg.html" target="_blank"><img src="http://i924.photobucket.com/albums/ad83/Christopher_Bush/Mobile%20Uploads/stengine.jpg" border="0" alt=" photo stengine.jpg"/></a>


See how much the rear of the head overhangs the flywheel?
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Old 10-09-2015, 07:13 PM   #10
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Move the rack at your own peril. Moving the rack forward will induce all sorts of nasty issues that are completely uncorrectable. Moving the rack down will induce a ton of bumpsteer, more than we already have. You really want to move the rack up, if anything.

Look at the K-series swaps for the level of effort that you should go through in your quest to not move the rack. It's massively important to the dynamics of the car.
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Old 10-09-2015, 07:47 PM   #11
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Move the rack at your own peril. Moving the rack forward will induce all sorts of nasty issues that are completely uncorrectable. Moving the rack down will induce a ton of bumpsteer, more than we already have. You really want to move the rack up, if anything.

Look at the K-series swaps for the level of effort that you should go through in your quest to not move the rack. It's massively important to the dynamics of the car.

Thanks! They did a lot of work with the K-series. It looks like it's also a tall engine. Depending on how creative I want to get at the firewall, I may be able to move the rack up somewhat. I'm supposed to pick the engine up sometime in the next week or so, but I'm still waiting for a transmission. I'm not cutting anything until I have the entire setup. I hate reworking my own work.
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Old 10-09-2015, 07:55 PM   #12
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Dry sump.
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Old 10-09-2015, 08:47 PM   #13
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Cosworth makes an off the shelf unit, but it's spendy and doesn't change the oil pump location.

These are the Mustang parts:

<a href="http://s924.photobucket.com/user/Christopher_Bush/media/inlettube.jpg.html" target="_blank"><img src="http://i924.photobucket.com/albums/ad83/Christopher_Bush/inlettube.jpg" border="0" alt=" photo inlettube.jpg"/></a>

<a href="http://s924.photobucket.com/user/Christopher_Bush/media/mustangoilpan.jpg.html" target="_blank"><img src="http://i924.photobucket.com/albums/ad83/Christopher_Bush/mustangoilpan.jpg" border="0" alt=" photo mustangoilpan.jpg"/></a>


Oil pump position in block:

<a href="http://s924.photobucket.com/user/Christopher_Bush/media/oil%20pump.jpg.html" target="_blank"><img src="http://i924.photobucket.com/albums/ad83/Christopher_Bush/oil%20pump.jpg" border="0" alt=" photo oil pump.jpg"/></a>

Last edited by cheeseclock; 10-09-2015 at 09:16 PM.
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Old 10-09-2015, 11:10 PM   #14
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I cant find the build thread but there is (was) a guy running the mzr in a green NB for drifting. Edit: found it. https://www.miataturbo.net/engine-pe...e-65621/page2/

Last edited by ThunderKunt; 10-09-2015 at 11:22 PM.
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Old 10-09-2015, 11:21 PM   #15
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I saw a few photos of that, but only top of engine shots and apparently drift guys often move steering racks for extra range (don't know the correct term) at full lock.
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Old 10-10-2015, 01:26 AM   #16
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If you notice, he also has the engine clocked slightly. This is really a great idea and something my buddy and I were discussing. It rotates the engine off the oil pump. Since the MT82 has a divorced shifter assembly, as long as the trans could sling oil, I can rotate it a bit, although it would make draining and filling a pain in the ***.
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