Suspension, Brakes, Drivetrain discuss the wondrous effects of boost and your miata...
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Old 12-28-2015, 08:56 PM
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Old 12-29-2015, 10:36 AM
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ok, can you do the same thing with the sm clutch/flywheel?
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Old 12-29-2015, 10:48 AM
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Originally Posted by thumpetto007
ok, can you do the same thing with the sm clutch/flywheel?
If you send me one and pay labor lol.
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Old 12-29-2015, 10:59 AM
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Do you find engagement a little more touchy/stall prone?
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Old 12-29-2015, 11:02 AM
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Originally Posted by psyber_0ptix
Do you find engagement a little more touchy/stall prone?
Yes. But totally manageable. Like just takes a few times to get used to it.

See my video where I'm doing a 3 point turn in my garage with no issue.
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Old 12-29-2015, 11:03 AM
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Originally Posted by thumpetto007
ok, can you do the same thing with the sm clutch/flywheel?
Twin will free rev faster than anything except a 7.25" single or a 5.5" because MOI is a thing.
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Old 12-29-2015, 01:19 PM
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All praise mr. @emilio700. This thing is seriously amazing. Thank you so much. Its hands down the best thing I've installed on my car, turbo included.

Here's a trip to mexico to show off some more.


With included log. I have a ways to go on hand movement. Andrew says he can do 150ms shifts, and I'm moving my hand as fast as I can
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Old 12-29-2015, 02:06 PM
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Lots of <150ms shifts in this video. Probably a few sub-100ms as well. The Racepak>AEM serial cable logs TPS at only 10hz, and it wasn't picking up the throttle lift on some 5-6 shifts.

949 7.25" metal twin, Manley rods, ST pistons, stock crank.

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Old 12-29-2015, 02:11 PM
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Very cool Andrew, thanks for the visual. I can definitely tell its possible. Maybe I just need a short shifter now. According to logs i'm at like 200ms right now, just messing around.
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Old 12-29-2015, 02:59 PM
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The one thing I did do on that car is shorten the clutch pedal travel to about half the factory travel. Shifter was stock, and I had little mechanical empathy on hot laps to get the most out of the car.
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Old 12-29-2015, 03:00 PM
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Thats what I want to do. But not sure how much I can lower it. Threw an email to 949 but you might be able to answer this. How low can I adjust the release. And after I adjust it down a ways, I can just take up all the free play right?
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Old 12-29-2015, 05:51 PM
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Originally Posted by aidandj
All praise mr. @emilio700. This thing is seriously amazing. Thank you so much. Its hands down the best thing I've installed on my car, turbo included.

Here's a trip to mexico to show off some more.

Turbo Miata Twin Disc Flat Foot Shift - YouTube

With included log. I have a ways to go on hand movement. Andrew says he can do 150ms shifts, and I'm moving my hand as fast as I can
I'm surprised you let the RPMs fall as much as you do. Is that because engine accelerates so quickly after the clutch switch is made?
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Old 12-29-2015, 05:56 PM
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Its what I have flat shift set for. I haven't really toyed with it. But that seemed to be almost perfect, no jerkiness or anything.

In reality it should probably be around 5250 to take advantage of my 7000 redline and line the mph up perfectly.

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Old 12-29-2015, 08:16 PM
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Originally Posted by aidandj
Thats what I want to do. But not sure how much I can lower it. Threw an email to 949 but you might be able to answer this. How low can I adjust the release. And after I adjust it down a ways, I can just take up all the free play right?
The idea is to have zero freeplay anywhere in the stroke. i.e. no freeplay at the top and no excess travel at the bottom. You can do this by cutting the clutch rod, dropping the engagement point to the floor, and using the clutch switch to hold the clutch pedal lower all the time, or you can adjust freeplay to zero at the top, then install a clutch stop to limit downward travel. IIRC Emilio suggests/used to suggest doing the former, I did the latter. Both achieve the same goal.
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Old 12-29-2015, 08:18 PM
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Awesome. Thats what I think I did. I might switch to using a clutch stop though. Depends on if my gf can reach the clutch as is.

Having it right at the floor allows for really easy modulation with your ankle.
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Old 12-29-2015, 09:22 PM
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If you hold RPM up, you should hold more spool (EDIT: Boost), making the flat shift not only faster, but the power comes back faster as well. The lightened flywheel does do well. My stock flywheel doesn't let RPM's get down to that 5200 by the time I re-engage.
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Old 12-29-2015, 09:25 PM
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Gotcha, I don't want a ton of shock load though, so I'm ok with how it spools. It holds about 4-6psi.

So the hole for the current clutch stop can be opened up a bit. Going to stick a long m8 in there with 2 nuts, and move the clutch stop up quite a bit. This will give me the short travel, without the long reach. Its what andrew was talking about before. I'll post pictures when i do it.
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Old 12-30-2015, 05:35 PM
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I use the native switch to lower the resting point of the pedal by just threading it down further. Then adjust pushrod to achieve disengagement just above the bottom of the stroke. With practice, you don't depress the pedal as much as you stab it while snapping the shift lever. 150ms upshifts with our light B6 flywheel is possible but that's about the limit and requires healthy syncros. With practice you can click off 100ms upshifts with the twin and less than healthy syncros. If the syncros have no work to do, they don;t have to be in that great of shape. Biggest difference for me with the twin is downshifting where you need to increase revs (as opposed to decrease) to shift quickly.
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Old 12-30-2015, 06:20 PM
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Very nice, thanks for the side-by-side. Even my GF who rarely drives stick could easily notice the change and says it sounds like a very different beast. We're both excited to get my twin installed as well.

Off-topic but related to the setup, anyone know why the organic was discontinued? I can't find any information anywhere on this.
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Old 12-30-2015, 06:27 PM
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Originally Posted by emilio700
I use the native switch to lower the resting point of the pedal by just threading it down further. Then adjust pushrod to achieve disengagement just above the bottom of the stroke. With practice, you don't depress the pedal as much as you stab it while snapping the shift lever. 150ms upshifts with our light B6 flywheel is possible but that's about the limit and requires healthy syncros. With practice you can click off 100ms upshifts with the twin and less than healthy syncros. If the syncros have no work to do, they don;t have to be in that great of shape. Biggest difference for me with the twin is downshifting where you need to increase revs (as opposed to decrease) to shift quickly.
Adjustment: I did what you said and it made it awesomer. Makes for modulation with my ankle easier too. But its too low for my gf to reach, so I'm going to adjust the stop up a bit and lengthen the pushrod.

Syncros: holy **** yes. My syncros were in poor shape with my Fidanza, they didn't like shifting fast. With the twin they are totally happy.

Der_idiot: Emilio has said why elsewhere. I forget why though. I really like the organic. It drives just perfectly. Clutchnet said they could make organic discs for $250. I got mine resurfaced for $100
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