Rev Match!!

[AnelBHF]

How well does the Camaro manual rev match work in street situations? Specifically when going from a high gear such as 5th to 2nd when 2nd will be at high revs, such as 5K, after the shift how quickly does the engine get from very low revs up to 5K? A big engine with heavy flywheel and pressure plate has a lot of inertia.

Also, I assume that the rev matching is not a substitute for reducing syncro wear via double clutching since the system won't know the target gear until the gear is selected. By then the syncros have already done their job.

FYI Bravo I think you mean clutch "disengaged" from the engine as you row the shift lever between gears.

It's flawless on the corvette and camaro. Go test drive one and try to get it to mess up it still won't do it.
And for people that don't want to use you just don't have to turn it on.
I have seen on here that people buy aftermarket rev matching systems which never work as good as OEM systems. Not everybody can heel and toe so rev match can also be a good learning tool.

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[Bravo]

I enjoy doing it manually. wouldn’t have it any other way, what’s next auto heel and toe..... I know I’m old school.....

I totally get the purist mentality here.

For me, auto rev matching might be enough to get me behind the wheel of a 6spd.

I don't drive manual cars...never really have. I understand how the mechanics work, and I have about 2 minutes behind the wheel of one in a parking lot.

I big part of me wants to own a manual car, but having never really driven one is very intimidating - I'd be very hesitant to drop $30K+ on a car that I might not like to drive. :(

I probably wouldn't even be able to convince myself to test drive a manual, as I would make a complete fool of myself.

 

[Rocketman]

Rev matching would be especially great for us track newbs who need to focus more on our lines than shifting. And as long as it can be defeated then there really is no argument against it.

 

[5.0 435]

My 18 GT in sport mode has a very responsive throttle and it very easy to rev match by blipping the throttle. I don’t feel I need it. My corvette had rev match and was nice because the throttle response was very lazy.

 

[Epiphany]

How well does the Camaro manual rev match work in street situations?

I spent some time tracking and street driving a brand new 2017 SS 1LE. The rev match feature works flawlessly both on track or off. It is more aggressive than I would have thought an OEM would do in this day and age and exactly how I would want it. One click of a paddle and it is on or off - instantly. I discussed the feature with someone working on development of the GT500 and pushed the point hard that the next Ford simply has to have it, no excuses. That and something like GM's PDR. Both are must have items for tracking IMHO.

 

[TexasRebel]

I think the manual rev match would actually be right 100% of the time, because it isn't anticipating anything. All manual rev matching does is match the engine speed to the transmission speed depending on the gear that you select.

For instance:

You're driving 40mph in 5th gear. Your RPM is at...1700ish? (Forgive me, I am not great with gear ratios/rpms).

Now you want to pick up the pace. You push the clutch in and drop down to 4th.

With rev matching, the RPMs will increase the moment that you slide the shifter into 4th (with the clutch still depressed). The RPMs will hold and match based on 4th gear at the given speed (the RPMS will slowly fall as you coast and slow down). Lifting the clutch will result in a smooth transition into gear.

Now you could also hold the clutch while in 5th and go to 4th (RPM jump), still with the clutch engaged go to 3rd (another RPM jump), and then to 2nd (probably close to rev limiter at that point). The rev match will let you row through the gears while at speed, and the engine will attempt to match the speed at every gear to allow for a "smooth" transition into gear.

In other words, it isn't guessing. It knows what RPM to hold for that gear.

...I think I just repeated myself a bunch of times in this post.

Except these cars don't know what gear the M6 is in (other than Reverse). If they know at all, it is strictly based on engine RPM v. Speed... which would be unknown until the clutch is engaged.

At some point, for automatic rev-match for the M6 to work, you would have to tell the car you plan to up or down shift.

There are exactly zero sensors on the input side of the transmission.

 

[Bravo]

Except these cars don't know what gear the M6 is in (other than Reverse). If they know at all, it is strictly based on engine RPM v. Speed... which would be unknown until the clutch is engaged.

Doesn't it display your gear on the dash? I could swear that I saw the LCD dash with 6MT showing the current gear.

If it does, then the computer absolutely knows which gear your in. It also will know the proper RPM for all other gears at the vehicles current speed.

The only lag will be in the engine getting to that RPM once the selector goes into any given gear, and the computer will input that RPM far more quickly and precisely than any human could.

 

[TexasRebel]

Doesn't it display your gear on the dash? I could swear that I saw the LCD dash with 6MT showing the current gear.

If it does, then the computer absolutely knows which gear your in. It also will know the proper RPM for all other gears at the vehicles current speed.

The only lag will be in the engine getting to that RPM once the selector goes into any given gear, and the computer will input that RPM far more quickly and precisely than any human could.

It does not.

You saw the A10 in Sport mode.

 

[TomcatDriver]

Except these cars don't know what gear the M6 is in (other than Reverse). If they know at all, it is strictly based on engine RPM v. Speed... which would be unknown until the clutch is engaged.

At some point, for automatic rev-match for the M6 to work, you would have to tell the car you plan to up or down shift.

There are exactly zero sensors on the input side of the transmission.

How about on the output side? I would be suprised if there is not an output from the transmission that tells the ECU what gear it's in, but the ECU needs to know before it's acutally in gear. I would think you need a sensor on the shifter or in the shifter linkages somewhere so the ECU knows when you are passing through the gate to 3rd (for example).

 

[Bravo]

It does not.

You saw the A10 in Sport mode.

I'm not a gambling man, but I would bet big money that the car knows the exact position of the 6MT shifter at all times, even if it's not displayed.

 

[TexasRebel]

So... Tomcat is surprised and Bravo needs to decide how much "big money" he wants to give up... addle:

How about on the output side? I would be suprised if there is not an output from the transmission that tells the ECU what gear it's in, but the ECU needs to know before it's acutally in gear. I would think you need a sensor on the shifter or in the shifter linkages somewhere so the ECU knows when you are passing through the gate to 3rd (for example).

The only gear with a sensor on it is reverse (lights, camera). Other than that, the ECU really doesn't care what gear you are in... the only reason the ECU would need to know is for rev-matching, which isn't a feature for these cars. It could also be done by sensing the rotational velocity of the input shaft (simpler electronics: 1 sensor monitoring the lay-shaft instead of 6 open/close switches). That would also come as an added expense (parts, programming, warranty).

 

[Bravo]

So... Tomcat is surprised and Bravo needs to decide how much "big money" he wants to give up... addle:



The only gear with a sensor on it is reverse (lights, camera). Other than that, the ECU really doesn't care what gear you are in... the only reason the ECU would need to know is for rev-matching, which isn't a feature for these cars. It could also be done by sensing the rotational velocity of the input shaft (simpler electronics: 1 sensor monitoring the lay-shaft instead of 6 open/close switches). That would also come as an added expense (parts, programming, warranty).

Haha - I totally understand where you're going from - I just have to believe that the ECU on these modern vehicles knows exactly what is going on with the transmission. Sensors are relatively cheap.

Do you by chance have any documentation that shows that the ECU is clueless regarding selected gear?

 

[l'Ingegnere]

It does not.

You saw the A10 in Sport mode.

There was a picture on Instagram of a pre-production Bullitt with a gear position indicator in the display. It's possible they may have added additional hardware for MY19 to support this feature.

 

[l'Ingegnere]

Just as general information, GM has actually employed 2 generations of its rev-matching system. The first was introduced on the 2014 Corvette (I believe). That generation was entirely passive in operation, using final gear selection position sensors to dictate the rev-match. This resulted in a system that could be easily beaten on vertical gate downshifts.

The second generation was introduced on the 6th Gen Camaro. This system uses a type of strain gauge sensor in the shifter mechanism (not sure if it's in the shift box or on the forks themselves) along with predictive programming strategy. A close analogy would be a motorcycle quickshifter in that the car "knows" you're going to shift before the lever has reached the destination gate, making it much more difficult to "beat the blip".

 

[TexasRebel]

Haha - I totally understand where you're going from - I just have to believe that the ECU on these modern vehicles knows exactly what is going on with the transmission. Sensors are relatively cheap.

Do you by chance have any documentation that shows that the ECU is clueless regarding selected gear?

https://parts.ford.com/shop/en/us/new-transmissions/transmission-assy-7851933-1

7H103 is the only sensor... for output shaft speed.
15520 is the only switch... for reverse.

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