Well, perhaps NOT quite but it is the best thing that has been available for standard shift cars since synchromesh, IMO. I'll first say when and why and the in a Side Bar say why I use it 99% of the time! "lol"

Although it is functional for upshifts, unless you shift slowly, you won't feel a difference (or at least in 3 years with my C7, Z51 I don't!) so I'll show where it is very effective-downshifts! The M7 has 3 overdrives, 5th, 6th, 7th. You'll find you don't need to drive it like an old 4 speed, rowing thru all the gears! I usually go thru 1st, 2nd, 3rd and often 4th but then pick the overdrive that makes sense, i.e. for example accelerate in 4th or even 3rd to 70 mph when entering an Interstate then shift directly to 7th.

For the exit ramp you'll probably want to be back to 4th, direct drive. Just shift to 4th directly. I also hate driving next to 18 wheelers so may do the same to accelerate past quickly while on an Interstate (less exposure time to rocks and radar!) . The springs in the shifter are perfect to guide that move, just pull back with moderate force and you're in 4th. Now that is going from 1500 rpm to 3000 rpm. modulating the throttle, even for a good heel toe enthusiast (which I am) is NOT as easy as "stabbing" the throttle at high rpms when racing! The computer raises the rpm to exactly 3000 rpm and hold it for ~ 1.5 seconds while you reengage the clutch. Makes a perfectly smooth transition.

I also find it very useful in town when cruising at say 45 mph in 5th and making a 90 degree turn to another street, just shift directly to 3rd, may or may not even hit the brake and let engine braking slow the car. That is going from 1400 rpm to 2800 rpm. The computer raises the rpm to exactly 2800 rpm and holds it for ~1.5 seconds. Modulating the throttle with heel toe and getting it perfect is not easy, 100% of the time!

SIDE BAR: You may read some comments like, "A good driver doesn't need it etc." They may be referring to racing where, while braking, you can stab the throttle with your heel (or in a Vette side of foot) when downshifting, i.e. the next lower gear that will put it closer to redline. Every DD I have owned in my ~57 years of driving (was 74 yesterday!) has been a standard shift- yep and old gearhead! I got quite good at "heel-toe" at higher rpm's even with cars and two trucks where the peddles were not as nicely placed as the Vette! In fact this is my 3rd 7 speed! Had a Dodge Colt turbo twin stick 7 speed and a Doug Nash '88 Vette with an electrically operate overdrive on a 4 speed trans.

However found in my C6 6 speed it was not easy, when skipping gears on downshifts to get that perfect or near perfect match. A good example is the 4 lane 65 mph divided highway that I leave when turning to the road to my home. It is a 25 mph limit twisty road. If driving in 5th or 6th at 65 mph I would shift directly to 3rd for the turn and half the time get a good match-the other half it was not. In the C7 it is perfect every time!

By the way for the Interstate 7th to 4th for passing, when you go back to 7th just do it directly and you'll see cruise control reengages automatically! First car I have owned that does not disengage overdrive when the clutch is depressed!

Try it you'll like it, IMO, if you understand where it is most useful!

 

I use rev match as a performance enhancement. It matches engine and transmission RPM allowing faster acceleration after a down shift. Wrongly used the car will leach forward when the clutch is re-engaged. I use rev match less than five percent of my shifts.

 

... RM is the best kept secret to render euro drivers in total awe and bow to LT1.

 

As you say wrongly used it can over-rev. For new C7 M7 Vette owners here is what I have found re "over-revving."

This have been a forum comment from some folks for the 3 years I have had my September 2013 built C7, Z51, M7. I conducted a test to see if I could get it to occur, as early on I did feel that one or two times. I was able to duplicate an over rev situation doing something it cleanly says NOT to do with Rev Match either intentionally or unintentionally.

I was driving in 5th at 45 mph and was making my usual shift directly to 3rd. While moving the shift level to 3rd I purposely moved to the 1st 2nd gate. I DID NOT go into either gear just moved the level a bit too far to the left in the neutral slot. The engine revved as if I was going to put it in 2nd! The Hall sensors provide info to anticipate where they "think" you're going to shift and rightfully told the computer it was 2nd! When I shifted quickly to 3rd the engine was at a higher rpm than needed for that gear!

Also, it only holds the proper rpm for a short time so don't left the car slow before you downshift and reengage the clutch. Downshift quickly. If you shift and reengage the clutch slowly the car will NOT be at the speed needed for the perfect match so the rpm will be higher. Since I don't shift slow, up or down, I don't find it an issue.

A habit I had to break also messed up the computers built in logic! With my C6 I often went from 5th or 6th when making a turn to another road. I would go to 3rd BUT as I have done in prior cars when skipping gearts, with the clutch still depressed I would move the shift level into the missing gears! That spools up the cluster gears. CAN'T DO THAT WITH REV MATCH! In fact it is warned about! Confuses the computer! I no longer do that, as it says, "Go directly to the lower gear you intend to use." Rev Match makes it a perfectly smooth match.

Hope that Helps some new owners.

 

Reading through the messages I thought "Gee I didn't see anything snarky" so I went back up to re-read Silver Stingray's message. Turns out I didn't see it because he's on my ignore list from a while go! I see he still hasn't changed his tune...

 

I describe rev match with 3 words - No engine braking. People with manual trannys know that if you downshift into a gear it can slow you down if the RPMs are below the RPMs needed to maintain the current speed. That's called engine braking. With RM there is no engine braking because the computer matches the RPMs needed to be traveling at this speed as you are going into the gear the computer sensed you are selecting.

I find it great for when you are going between 2nd, 3rd and 4th down windy mountain roads of which there are many here in Southern California. Another good place is where you're in traffic (yes I said traffic) but moving at a relatively decent pace and there are large "holes" in the traffic. It's great to drop to say 4th while making that lane change into that big pocket.

 

Your lack of support and friendliness is not compatible with the Corvette community. Please make your next post in the "C7s For Sale" section. Move along now.

 

Obviously he is talking about when we use the A8 in Manual mode.... I also enjoy the automatic rev matching on the A8 - it is quite noticeable when going down into 2nd and 1st. I've never found any "on/off switch", so I'm thinking it's something that is just "automatic" (no pun intended), but it is definitely doing it. I'm assuming part of the auto transmission programming...

 

Hmm, in a manual, rev-matching uses the electronic throttle to keep the engine at correct speed when it's disconnected from the wheels (eg. clutch is in), so that when going to a different gear, the engine is ready for the clutch be pulled out.

In an automatic, the wheels are always connected to the engine through the fluid torque converter. The transmission is slipped between gears by solenoids trapping or freeing planetary gearsets. So, the engine speed is naturally equalized between shifts as the solenoids slip or engage the various rings, and this is done without the use of electronic throttle control. The TCM is great at varying the speed at which these solenoids engage, which results in the quick snappy shifts under acceleration or smooth unnoticeable shifts at cruise.

So, I'd say an automatic has a sort of "rev matching" capability, but not in the same sense or functionality as in a manual, which is often disconnected from the wheels.

In an automatic, the engine is sped up as a result of the transmission solenoid engaging different gears. In a manual with rev match, the engine is sped up before the gear has even been engaged.

 

People often forget that rev match is good at keeping the revs in the upper band for up shifts too.

 

Great response and idea. I'll try to find the ignore list and place him at the top!

 

thanks for attaching the video. I fully understand it now!

thanks,
Joe

 

I tried RM and didn't like it.

1) I don't like the engine doing something on it's own, not commanded by me. If I want revs to match, I'll make em match. That's what my right foot is for.

2) Often, I don't want revs to match. When upshifting, I want lower revs. When downshifting, I want higher revs. Sometimes I want a little engine braking. (I don't abuse this.)

3) If I want smooth, no problem, I feather the clutch. (I understand this causes wear.)

I learned to drive 3-on-the-tree during high school driver ed. The instructors taught us to get off the gas momentarily while the clutch was disengaged.

My first car was 4-on-the-floor (Triumph TR4). I've driven sticks ever since. That doesn't make me any kind of expert. I never tracked a car and never learned heal-toe.

If I'm doing something wrong or not understanding something, I don't mind being told.

 

Great thread as I'm really wanting the M7 in my 2017 Z06. It's been 20 years since I drove a manual and that car certainly didn't have Rev Match.

 

I'm 66.

To me rev matching is something that a driver of a manual trans car does instinctively when shifting gears. It is a learned skill that is very important to the mechanical survival of the clutch and transmission and perhaps even more.

Briefly put when shifting the engine rpm must be adjusted to be what it will need to be in the new gear for a smooth transition. Growing up I/we learned to do this matching as a reflex based upon our experience. The faster the shifts are performed and higher the power output the more important the rev matching becomes.

The computations required to be successful at rev matching are, for my generation and prior generations ( and perhaps some younger drivers ) , done between the ears in an area otherwise known as the brain.

I was totally incredulous upon learning that GM had automated this. I must assume that they did this as a result of market research that indicated that younger potential buyers had never learned to properly drive a manual transmission car.

My opinion is and will remain that anyone who needs this automated rev matching does not understand shifting a manual trans car, probably never learned, and is allowing the software to provide a crutch.

It would be the first nanny that I would unplug. If I were to use the automated rev matching serious loss of self esteem would result. Not only that my enjoyment of driving a manual would just about evaporate if a computer did for me what I have always done myself.

Anyone who uses this nanny should shut it off now and learn to drive a manual trans himself. You're not really capable of driving a manual trans if you must use rev matching software. I apologize in advance if these opinions upset people. However, I have a huge amount of experience driving all manner of manual trans muscle cars and, at this point in my life, would have to say I know what I am talking about.

 

I too learned to drive a 3 in the tree in high school drivers ed. I also have had many stick shift cars and I can heal and toe well. At first, and for some time, I did not like ARM. But after seeing some of these videos etc. I decided to give it another try. I'll admit I had to use it for a while, learn how to use it, and learn to 'let go' of old (good-bad-different) habits. Now, I find it a lot of fun! You only need it when you are using your Corvette as a sports car.

 

It doesn't bump the rpms that much. Besides you won't be pushing the engine that hard until it warms up. I engage it as soon as I start the engine. Nannies that work properly are great and this is one that works fantastically.

Bill

 

I'm not an expert but I do own an A8 and believe it does work with an auto. Try using the paddles to downshift from say 4th to 2nd quickly, you will hear and feel the car revmatch. But be prepared to be surprised and jolted as the gears kick in. I could be wrong about this and what I have experienced could very well be called something else in the A8 toolbox!

also, on an M7 car it is my understanding that the car can determine from where you are moving the shifter, up or down, it will determine the correct Rev Match to apply.

 

Try Rev Match again when you're just cruising and when making slow speed turns, try skipping gears like 5th to 3rd when making a turn or on an Interstate when in 7th go directly to 4th when exiting. You may like it. Your car your choice, there is nothing wrong or right!

 

Hmm, I'm 74 and have only had standard shifts in my DD's including two trucks. I heel-toed in all including those trucks (and some others) where the peddle position did not make it easy!

The C7 is my 3rd 7 speed! The first was my Dodge Colt Turbo with it's twin stick shifters (like an 18 wheeler) and the second the Doug Nash 4 speed that came in my '88 Vette that had an electrically activated overdrive in 2nd, 3rd, and 4th-hence 7 speeds if properly selected with the button on top of the gear shift.

However the C7 has 3 overdrives and unlike my other cars (except my C6) I shift it differently. I usually row thru 1st to 4th, then pick the overdrive that fits where I am driving. On an Interstate, for example 4th directly to 7th. Or often for fun I accelerate to 70 mph in 3rd (that is only ~4400 rpm) then shift directly to 7th.

When leaving the Interstate and going from ~1500 rpm I downshift directly to direct drive, 4th ~3000 rpm. Where my rev match skills are good when driving aggressively and downshifting where the rpm will be in the 5000 + rpm range, quickly calculating the required rpm at lower speeds skipping two gears is not that accurate or fast (and I'm very good at math! )

An even better case is when cruising in my most common gear 5th (the first overdrive) and making a turn to another road where I often don't even have to use the brake (as with my normal heel-toe,) I just shift to 3rd where I want to be after the turn to the other road. Again that is going from ~1200 rpm to ~3000 rpm. Rev match makes those calculations perfectly, better than I can especially when not driving aggressively!!

I'd suggest that even Juan Fangio or Phil Hill could not get those lower speed heel-toe matches as good as the computer can with Rev Match!

Your comments don't upset me at all, I think you just don't understand how and where to use Rev Match. Or perhaps you don't skip gears and row through every one up to 7th and downshift from 7th, to 6th, to 5th, to 4th when existing and Interstate. Or perhaps you think you're better than Fangio or Hill! Both of them could also double clutch a non syncromesh trans when shifting as well!