FFtec Examines the EcoBoost Clutch

We had our trans off last week to do a clutch upgrade so I thought I'd share some pics and info about the EcoBoost clutch system.

First, it uses a hydraulic throw out bearing like the previous Mustang. It's a nice system with light pedal pressure and minimal friction. It has a couple of quirks; 1. Since the slave cylinder is mounted in the bellhousing the line must be disconnected when you remove the trans. 2. There's no bleed fitting on the slave cylinder so it requires a vacuum fitting to purge out any bubbles after it's reconnected.

You'll also notice the input shaft on the trans is upgraded on the new Ecoboost. Older Mustangs used a coarse 10 spline shaft that was prone to twisting at high torque levels. Ford was wise and gave the EcoBoost the stronger 23 spline shaft.



The shifter mount is a nice upgrade over the older version. As you can see it uses a rigid cast aluminum truss style construction for a direct connection to the trans. The shifter has a nice, direct feel. It only takes a couple of aftermarket bushings to firm up the shifting feel even more.



The pressure plate is a little different. It has a self adjusting mechanism inside the cover which compensates for the disc thinning as it wears down. The main benefit of this feature is that the pedal pressure remains consistent over the entire life of the clutch. Here's a close look at the self adjusting mechanism in the pressure plate.








The flywheel is a heavy dual mass flywheel. It weighs 30.2 pounds! Like other dual mass flywheels it should not be resurfaced when replacing the clutch.



We installed an upgraded 6 puck friction disc on our '15 EB.




Yes that's a Borg-Warner twin scroll T4 EFR turbo in the upper right corner of that pic!

so...

about that lightweight flywheel and...
lightweight turbo... ;)

;)

wireless said:

so...

about that lightweight flywheel and...
lightweight turbo... ;)

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I'm the engine/trans guy. You'll have to check with the turbo and tuning guys for info on the turbo. I'm not allowed to say anything ;)
;) :cough:25psi@ 3krpm:cough:

We got the ball rolling on a lightweight flywheel project. I'd like to move it along faster since the stock flywheel is so heavy, I can really feel it kill the responsiveness when I'm hooning around. If you're a track junkie like me just give the shop a call. We'll see if we can work something out. :cheers:

Since you're an engine/trans guy, I take it that means you also deal with the head, etc?

My question is... and this is definitely off topic... does the car sound different with a different turbo? I haven't seen enough pictures of your swapped EB, but I'd love to see how it sounds now lol.

I'll probably be snagging some parts from you gents. You & Full Race are on my radar :x

wireless said:

Since you're an engine/trans guy, I take it that means you also deal with the head, etc?

My question is... and this is definitely off topic... does the car sound different with a different turbo? I haven't seen enough pictures of your swapped EB, but I'd love to see how it sounds now lol.

I'll probably be snagging some parts from you gents. You & Full Race are on my radar :x

Click to expand...

Yes! The car sounds awesome with the EFR turbo. I was kicking myself over the Holidays for not picking up a new phone sooner since I really wanted to catch it on vid. The turbo can be heard clearly during spoolup too.

The head is mass produced and has plenty of room for improvement.

As far as the stock EcoBoost Manual clutch. How would you rate it? My pedal is super soft and when dropping the clutch I would expect it to spin the factory summer tires. But oftentimes the clutch seems to grip well and cause the engine to bog. Which I guess means its doing its job, perhaps I should rev up higher on the launch. Would you consider it robust and grippy enough for tough launching (factory set up, which no one else may consider tough lol)? Any other pointers or facts that would be useful?

Thanks! New guy here, used to all motor manuals. The turbo thing is taking some getting used to as far as launching goes.

McCringleberry said:

As far as the stock EcoBoost Manual clutch. How would you rate it? My pedal is super soft and when dropping the clutch I would expect it to spin the factory summer tires. But oftentimes the clutch seems to grip well and cause the engine to bog. Which I guess means its doing its job, perhaps I should rev up higher on the launch. Would you consider it robust and grippy enough for tough launching (factory set up, which no one else may consider tough lol)? Any other pointers or facts that would be useful?

Thanks! New guy here, used to all motor manuals. The turbo thing is taking some getting used to as far as launching goes.

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Can't speak for how much power the clutch can take, but if you said the clutch is super soft. If you don't like the soft pedal you can take out the assist spring if you haven't done so already. Also makes it easier to modulate in daily use in my opinion.

That might help, I would guess you can feel it engage much better? I find it relatively difficult to feel the engage point currently. I will look into that. Thanks!

McCringleberry said:

That might help, I would guess you can feel it engage much better? I find it relatively difficult to feel the engage point currently. I will look into that. Thanks!

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It just feels more natural. Just be careful when you remove the spring because the top tabs break off pretty easy. I used regular vice grips and they slipped off when I was in the middle of pulling the spring out (should have used needle nose). Broken tab... But I don't plan on putting it back in so no worries.

McCringleberry said:

As far as the stock EcoBoost Manual clutch. How would you rate it? My pedal is super soft and when dropping the clutch I would expect it to spin the factory summer tires. But oftentimes the clutch seems to grip well and cause the engine to bog. Which I guess means its doing its job, perhaps I should rev up higher on the launch. Would you consider it robust and grippy enough for tough launching (factory set up, which no one else may consider tough lol)? Any other pointers or facts that would be useful?

Thanks! New guy here, used to all motor manuals. The turbo thing is taking some getting used to as far as launching goes.

Click to expand...

I like the stock clutch for stock and lightly modded power levels. The engagement could use better feel. The engagement point is somewhat obscured by the assist spring so it's hard to get a good launch. A couple guys were telling me they stalled the car on the street a few times until they got used to it. From what I've seen the assist spring isn't quite right. When the pedal is up the assist spring helps lift the pedal up. When the pedal is approx halfway down it helps push the pedal down so the pedal pressure feels lighter.
The assist spring seems to have a tipping point that doesn't exactly match the engagement point of the clutch. I haven't removed the assist spring yet but I plan to try it soon. I have time in my schedule next week to look at other assist springs, I'd like to install a spring that's lighter.

It always takes practice to get a good launch with a turbo car. Just make sure you don't slip it too much. The stock clutch can't handle too much heat, so if you slip it at full boost you'll glaze the disc and loose holding power.

That spring must be why I thought the clutch felt so weird when I did my test drives.

RubyRed15 said:

That spring must be why I thought the clutch felt so weird when I did my test drives.

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After removing the spring and turning off hill start assist it's loads better driving mine.

David@FFtec said:

We had our trans off last week to do a clutch upgrade so I thought I'd share some pics and info about the EcoBoost clutch system.


The shifter mount is a nice upgrade over the older version. As you can see it uses a rigid cast aluminum truss style construction for a direct connection to the trans. The shifter has a nice, direct feel. It only takes a couple of aftermarket bushings to firm up the shifting feel even more.

Click to expand...

This is encouraging. Does that mean changing the bushings may make an aftermarket shifter less of a necessity?

Potrillo said:

This is encouraging. Does that mean changing the bushings may make an aftermarket shifter less of a necessity?

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Yes, I'd say it's less of a necessity, but some people will want to install a better shifter anyway. There's no such thing as a shifter that's too good.