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Old 11-01-2011, 06:23 PM   #1
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Default Rev Matching

was just curious if the MS can be programmed to do rev-matching similar to what the 370z does.
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Old 11-01-2011, 06:24 PM   #2
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can a mod move the general MS section and not the PNP section.

Thanks.
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Old 11-01-2011, 06:27 PM   #3
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You mean auto-blip the throttle on downshifts? How would the MS go about doing this without an electronically controlled throttle body?
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Old 11-01-2011, 06:28 PM   #4
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Doubt it, seeing as Miatas don't have electronic throttle control.
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Old 11-01-2011, 06:29 PM   #5
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well i guess that was a short thread...
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Old 11-01-2011, 06:33 PM   #6
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Quote:
Originally Posted by Oscar View Post
You mean auto-blip the throttle on downshifts? How would the MS go about doing this without an electronically controlled throttle body?
A mega large and fast IAC valve (i.e. not the stock one) ?

Would require craze accurate idle control.... So scratch that.
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Old 11-01-2011, 06:39 PM   #7
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You could use a blipper solenoid.
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Old 11-01-2011, 06:40 PM   #8
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I'm guessing 370z has a sensor in the transmission to tell the ECU what gear it's in. Megasquirt can only figure out the transmission gear via combination of vehicle speed sensor, RPM and user-specified gear ratios.

Because of that, even if you could electronically blip the throttle, MS can't be programmed to determine whether you're downshifting, upshifting or just pushing in the clutch until after you release the clutch in and engine RPM rises/drops/remains same.
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Old 11-01-2011, 06:53 PM   #9
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Even harder to figure out if the loose nut behind the wheels goes from 5th to 3rd...

Sequentials are so much easier, they have a natural direction of gear change, and only one at the time.
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Old 11-01-2011, 06:55 PM   #10
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Mount a handbrake from a bike on the gear lever with a cable running to the throttle body and blip with your right hand while downshifting
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Old 11-01-2011, 07:01 PM   #11
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Or just learn to heel-toe...
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Old 11-01-2011, 07:08 PM   #12
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Quote:
Originally Posted by trickyrix View Post
Or just learn to heel-toe...
It'd be a lot less trouble to weasel out all the engineering challenges of teaching a brutally simple engine management system to know what gear it's in, what gear it's going into, what the vehicle speed is, what the corresponding rpm should be, how much throttle it needs to use to get there and stay there, and how to give it that much throttle, precisely and repeatably.

NM.
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Old 11-01-2011, 07:42 PM   #13
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Pretty soon people are going to want cars that can wipe their ***.
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Old 11-01-2011, 08:17 PM   #14
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^haha sooner than we think. We already got cars with massage crap in the seats, ones that automatically slow down when a car ahead of slows down, and a few that check blind spots for you!

But yea, heel-toe is not as difficult as it sounds really. Just make a pedal extension and bolt it into the stock pedal, voila! easy* heel-toeing while trying threshold braking.

*With practice of course.
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Old 11-02-2011, 09:11 AM   #15
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One way to figure out if downshifting or upshifting could be to analyze the delta-v during the last second.
If you are downshifting you usually have slowed down the last second, and if you are shifting up you usually have accelerated during the last second.
This could then be tagged into the flat-shift function (which doesn't care about vehicle speed as it is now I guess).
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Old 11-02-2011, 04:14 PM   #16
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Here's the device:




It is a pedal extender to allow easier heel-toe braking.
http://www.rennenmetal.com/proddetail.asp?prod=2280
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Old 11-02-2011, 04:44 PM   #17
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Put it in neutral around the turn because you can't drive.
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Old 11-02-2011, 05:17 PM   #18
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Quote:
Originally Posted by Track View Post
But yea, heel-toe is not as difficult as it sounds really.
It may have something to do with shoe size (I wear size 14 Timberlands) but I find it amazingly simple, no need for any kind of pedal extension.

The thing I find misleading about the term is that I don't really use the heel and toe to do it. I just step on the brakes with the ball of my foot, and roll my foot at the angle. I can easily hit the throttle with the side of my shoe, and honestly, it's a very natural movement. No contortion or having to think about where my feet are, just side-step the brake and feel for the throttle.

Last edited by Joe Perez; 11-02-2011 at 06:13 PM. Reason: mis-used an apostrophe.
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Old 11-02-2011, 06:00 PM   #19
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^its exactly how you do it. Heel-toe is a misnomer.

And shoe/foot size is a big factor. I tried to heel toe without an extension because every one told me it was so easy and comfortable to do it in the miata. Well, as an average sized male with a 9.5-10 shoe size, I practically drove off the track trying to heel-toe on the backstraight of RA. missing your braking at 110mph is pretty ****** scary. If you got average-small feet, go ahead and extend the pedal, but if you are big one, you might just be fine.

Heel-toe on the street is pretty silly, but I was able to do that fine. your foot lines up much more easily on the throttle pedal, because you aren't 2in deep on the brakes.
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Old 11-02-2011, 06:15 PM   #20
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Heel and toeing (or rev matching) is not silly anywhere. It is a skill, and like any skill the more you do it the better you get. You also get the benefit of keeping a neutral attitude on your car which helps your handling. This is also why I always do it when riding a motorcycle.
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