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auto blip - what am i missing?

Old 05-04-2019, 12:11 PM
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romandian
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Default auto blip - what am i missing?

if down shifting, you double clutch, right? well, i have done it for ages. the auto blip (ab) blips when you depress the clutch. so it speeds up the engine but does nothing for the trans, right? and you cant double clutch. why is that so, they could have done it right, no? (i only realized how it works after instaling it.)

besides, the device is not for the street at all. first when in town, everybody loooks at you as an idiot for blipping. second, the ab can blipp in certain situations when you are releasing the clutch, which makes my ls7 car jump several feet. (i almost hit a car twice because of this.) so, dont install it i a remote place, like i did, but put it somewhere you can reach, to switch it on and off between spirited driving and town. the glove box beeing the only place i can think of.

Last edited by romandian; 05-04-2019 at 12:12 PM.
Old 05-04-2019, 12:22 PM
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64drvr
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I never double clutch with or without an autoblip or active rev match. Autoblip’s purpose is to save the transmission through rev matching, among other gains.
Old 05-04-2019, 06:46 PM
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Racingswh
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I haven't double clutched since driving a Formula Ford. I am not sure why you would? Corvettes have transmissions that have synchromesh. I would think double clutching wastes time.

Regarding the auto-blip you just let it do its thing and let out the clutch immediately when you get into the lower gear. I would certainly turn it off on the street if you don't want it blipping.

I drove my Wife's car with it for the first time last week. For some reason I can't drive a C6Z without blipping myself. I had to turn it off. My Wife on the other hand loved it because she doesn't heel and toe to match revs when she down shifts. It made rev matching perfect and her down shifts seamless.
Old 05-04-2019, 10:03 PM
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phxcobra
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As others have replied, why would you need to double clutch. Plus,it's meant for the track, not the street right. I located mine in the ash tray so easy access but out of the way. Just use it on the track only.
Old 05-05-2019, 10:09 PM
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davidfarmer
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you heal/toe or rev match to keep the tires from skidding, causing a oversteer condition, not to protect you trans/engine/etc. If you downshift and release the clutch without some sort of rpm matching, good chance your back tires will pass you.
Old 05-05-2019, 10:46 PM
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Racingswh
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Originally Posted by davidfarmer
you heal/toe or rev match to keep the tires from skidding, causing a oversteer condition, not to protect you trans/engine/etc. If you downshift and release the clutch without some sort of rpm matching, good chance your back tires will pass you.
My experience has been a little different.

I've had to replace a differential prematurely in the Viper more than likely because of this and my abuse.

Very few drivers actually know how to heel and toe rev match. Even though I can and I'm quite proficient at it in the C6Z I can't do it very well in my ACR-E so in that car I feel the auto-blip works fantastic.

I remember years ago one of the very fastest drivers at a Skip Barber event at Laguna Seca used to smack the gear lever when changing down not using the clutch or matching revs. The tires would chirp with every downshift into T1.

There's another guy that I know who drives a Viper. He's one of the very fastest guys in one in the country. He does not rev match. Often times he lets the clutch out so quickly you hear the tires lock up and chirp.

So yes I would suggest that matching revs is gentler on the driveline, at least in my case when I am using very sticky slicks that shock the driveline instead of breaking traction, and I have seen with my own eyes drivers that have no clue how to do it go really quick regardless.
Old 05-06-2019, 07:36 AM
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Kubs
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Originally Posted by davidfarmer
you heal/toe or rev match to keep the tires from skidding, causing a oversteer condition, not to protect you trans/engine/etc. If you downshift and release the clutch without some sort of rpm matching, good chance your back tires will pass you.
This is exactly right.

If you think about it, when you go to down shift as soon as you push in the clutch the engine speed decreases. The tires however, are still moving at the same speed. Since you are selecting a lower gear, you need the engine speed to INCREASE to match the speed of the tires. If not the engine will try to slow the tires down as soon as you let the clutch back out and cause them to break loose, or drag like David mentioned.

If you're breaking drivetrain components then you are not shifting correctly.
Old 05-06-2019, 09:22 AM
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Racingswh
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Originally Posted by Kubs
This is exactly right.

If you think about it, when you go to down shift as soon as you push in the clutch the engine speed decreases. The tires however, are still moving at the same speed. Since you are selecting a lower gear, you need the engine speed to INCREASE to match the speed of the tires. If not the engine will try to slow the tires down as soon as you let the clutch back out and cause them to break loose, or drag like David mentioned.

If you're breaking drivetrain components then you are not shifting correctly.
Truth be told I don't shift very well so it certainly could be that. I would think that shocking the driveline could possibly cause premature wear.?

Here are my examples and they aren't great I know because I am still learning and have a long way to go.

As tedious as this is to watch it's me in my Wife's C6Z. That's just me blipping the throttle to match revs pre Auto Blip install. At no time do I stop in neutral, then blip the throttle, then change down to the next gear which is what double clutching would entail. I just blip while I am going to the lower gear.


In this example at Watkins Glen I am not rev matching effectively. After this season the differential in this car needed to be replaced.


Here I am using Auto Blip while having some fun with friends in their C6Z's. It may be coincidence but no differential issues so far since it's replacement.



As it relates to the OP it would be my preference to turn Auto Blip off if I were driving the car on the street. It doesn't work like the C7 so it's definitely intrusive in traffic and in parking lot's. With it switched on if you're braking and clutching as you're maneuvering the car slowly it's annoyingly blipping all the time.
Old 05-08-2019, 07:54 AM
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Kubs
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You are correct that the proper downshift order should be clutch in, downshift, rev, but they all kinda happen at the same time its so quick.

The term double clutching is actually clutch in, shift to neutral, clutch out, rev, clutch in, select gear, rev, clutch out. Its required to transmissions with no synchros in order to speed up the shaft the lower gear is on.

In your first and second video it sounds like you are over revving just a tad. If you let the clutch out while with the engine revving higher than needed, while you are still on the brakes, you can feel the car want to lurch forward for sec before the brakes grab again. This twists the input on the diff forward and back very quickly and can break the shaft or damage teeth on the ring and pinion.

Downshifting is hard, and takes lots of practice. If you had a blind deaf person ride in the passenger seat they shouldn't be able to feel your downshift when done properly.
Old 05-08-2019, 09:07 AM
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pjazz
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I love my Autoblip. At my age it's just one thing less to worry about while negotiating a turn and the rev sounds so sweet with my Akrapovic exhaust.
Old 05-08-2019, 09:46 AM
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fleming23
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Couple things - there is a little power button...turn it off on the street if you don't want to sound like a tool pulling up to red lights.

Regarding the blipping the throttle as you are releasing, your delay is too long. You need to adjust the dials better so that it blips the throttle more immediately when you press in the clutch. If the delay is too long, it will wait longer before it does the auto-blip, resulting in what you described.

I agree in that double-clutching simply is not necessary in the car, although could possibly save your synchros long-term (arguably).

Last edited by fleming23; 05-08-2019 at 09:47 AM.
Old 05-08-2019, 11:06 AM
  #12  
Racingswh
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Originally Posted by Kubs

Downshifting is hard, and takes lots of practice. If you had a blind deaf person ride in the passenger seat they shouldn't be able to feel your downshift when done properly.
It sure is for me. That's a definite.

I was never going to get it right in the Viper so I added the auto-blip and the car and I seem to get along much better now. I am still slow but hopefully the diff won't break again.

Jury is still out on the C6Z. I try and blip less now but it's still hard for me. I need to wait longer in the brake zone and blip less. I rush it and use a big blip for no reason.

So all I need to do now is shift better and go faster.

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