Never. But I don't track mine. If I did, I would experiment with it.

 

Thanks for the comment. I wonder if it's easier on the engine when you down shift.

 

Actually rougher on the engine since it is revving higher all the time.

 

I used rev match constantly. It is easier on the trans and hid my occasional screw ups.

 

Thanks for the reply. I like to use rev match for the same reasons. We are not alone, I think.

 

Not be contrary but Rev Match only engages when the clutch is depressed. Is simply replicates that throttle "blip" needed to shift smoothly into the next gear. This is what the owners manual say:

Active Rev Match: Vehicles equipped with a manual transmission have Active Rev Match (ARM). ARM aids in smoother shifting by matching the engine speed to the next selected gear. By
monitoring shift lever and clutch operation, ARM adjusts engine speed to match a calibrated value based on gear selection. On upshifts and downshifts, engine speed will be increased and
decreased to match vehicle road speed and transmission gear position. ARM is maintained for a few seconds between shifts, then deactivates if the shift is not completed.

Anything that makes shifting smoother is better for engine and transmission

 

I think that makes sense because truckers had to blip the throttle to shift gears fifty years ago.

 

I agree.

 

Just some info.

The Auto rev match is an automatic way to do the same as a toe/heal shift method. If the engine speed is not matched to the rotating speed of the trany then the clutch or rear tires take a hit. If one is downshifting and allowing the car to slow down between downshift then there is no need to toe/heal or use the auto rev match feature.

In general, downshifting should not be used to slow the car, the brakes should be used. Brake replacement is much cheaper than clutch replacement. Toe/heal downshifting is to keep the rear wheels from breaking traction on rapid deacceleration and be in a position to accelerate.

I use the auto Rev Match nearly all the time. It is much better on the engine & clutch system (and sounds great). The times I don’t use it are when I am is slow moving areas like a residential area. The system will cause the engine to rev just a bit on slow shifts (up or down). This is not detrimental to the engine in any way, but can be a bit annoying.

If you are shifting slow up or down then Auto Rev Match is not doing anything for you but is doing no harm. If you are shifting quickly and not matching the engine revs to the trany then wear is being caused in the clutch as it now needs to slip to make the engine-trany revs match.

The comment on truckers blipping the throttle is true but was due to the lack of synchronizers or good ones in the trany. This was often done with a blip of gas and many times with a double clutch action. Watch the Bullitt car chase. Steve McQueen does a fantastic job of shifting. You hear his double clutch on the upshifts. Our corvettes have great synchros so double clutching is not ever really needed. But I sometimes do it because it sounds so cool.



Use Auto Rev Match or not, I am just offering some information as to what it is and why..

 

I appreciate your thoughtful reply. Using the engine to slow the car down was my next question. You answered it very well. Thank you'

 

I have the same thing happen. I think it occurs when I don't cleanly move the shift lever from 1st to 2nd. If i pull cleanly along the shift path it doesn't happen.

 

I like to blip the throttle myself on down shifts.

 

That's a skill that I have not mastered. You are to be congratulated for being able to do it.

 

Quite frequently when my wife is in the car and I want to drive hard. Reflexes ar age 73 are not as good as when I was younger.

i use it frequently when my wife is in the car. At age 76, I am not as quick as when I was younger.

 

We all slow down a little with age. Thank you for responding to me question. I appreciate your input.

 

I use it all the time . Makes for smooth shifting especially when downshifting hard. Great feature for every day driving not only tracking

 

Then you might as well drive an automatic.

 

When I was at Spring Mtn for the Corvette owners school, I asked the director how he used it. He said he used all the time, except when he was on the track and then he used the heel and toe method.

 

Thank you for your taking time to reply. That's interesting.

 

100% of time.

 

Always, even when I’m not driving. I always try to match my wife’s revs when we’re talking to avoid any breakdowns.😂

 

Very often, and I never track it. I find It has two purposes on the street. I often coast in neutral and depending on traffic and hills, so when I re-engage my transmission I use rev-match to be smooth on the drive train, choosing the gear that is highest (lowest rpm) for the speed I am at. Secondly, it allows me to be a bit dramatic with my Borla Attak and headers when I approach a corner and am slowing down. I don't really use it for its intended engine braking, but to be easy on the drive train, so I am constantly turning it on and off - making those mocked repurposed shifter pedals quite handy. It can be excessive at times as it seems to be using max throttle to quickly get the revs up - and this does ruffle feathers as well as twist panties.

 

Never use rev match but my son likes to.

 

More info. I have been a powertrain engineer for 50 yrs, so I geek out on this stuff so bear with me.
I try to just present data so here goes.
The heal/toe is generally toe on the gas and heal of the same foot on the brake. The other foot is on the clutch. The reason is to make smooth downshifts, save the clutch disk and keep the tires from breaking traction. The Auto Rev Match replaces the “toe” part of this work.

With the Auto Rev Match on.
This all works with a lot of magic going on. Down in the trany/shifter are a few sensors. These tell the computer what gear you just came out of and what gear you are going into. It senses when you come out of gear gate to neutral and when you move the shifter to the new shift gate area. If you shift slow you can hear two engine blips one for coming out of the gear and one when you start to put it into a gate/gear. This info is sent to the engine computer.

Next the real work starts. The engine knows eng speed, vehicle speed, gear out and gear in rotation. It also controls TB position, valve timing, fuel. It has a number of look up tables it goes to for a number of other parameters, torque and misc others. So when down-shifted quickly it takes the engine speed to the proper rpm for that gear/vehicle condition. It does that using these other measured and controlled eng parameters. So the eng rev is not just a blip but a very well calculated eng condition to make the best match for all the parameters. If shifting slow then it may sound like just a blip.
I pulled up my Z06 gear charts. A typical downshift I do is a 4th to 3rd gear shift with hard braking. I target about 3000RPM . This is no more than a 500 rpm mis match in engine speed. My downshifts take about .2 sec or less. This is about 10 engine revolutions. So with the use of Auto Rev Match the engine might see as many as 10 revolutions during the shift and likely fewer. And the speed of the engine is in the band where it is meant to produce the correct power (timing& fuel are all adjusted properly). These calculations happen between 50 and 400 times a second. The engine is not over revving or over working it is controlled to the speed it needs to be. It is in its happy spot for that shift.

Now if one does not use rev matching or a toe blip, the clutch & synchro must take the hit for these engine rotations until the 500rpm mis match in speed becomes close enough to stop clutch slipping. This generates heat in the clutch, extra wear on the synchronizers, and sometimes a bit of gear clunk. One way or the other the engine speed must match the vehicle speed conditions.
If shifting slowly the computer can not predict just how slow or fast you push the gear selector into the final position so it may have the eng revs drop off slower than desired- sometimes called engine hang. This is what many don’t like about the Auto Rev Match.

I hope this might shed a bit of light on the matter.

Ok and now double clutching: For up shifting or down shifting. There are a few different names for this and a few methods but in general the following is the general idea.

This method is used with older manual tranys that did not have synchros or the synchros were not very good. So what a synchro does is synchronize the speed of the input gear to the speed of the output gear it needs to engage with. Gear teeth have to match or they grind very badly. So, if you just pushed in the clutch and shifted up a gear, one of the gears was not turning the proper number of revs. So, an angled ring is placed on the gear shaft to slip into the gear to help bring it up to speed so as not to grind the gears this piece is the synchro. If this was not present or not working good enough when you shifted then you needed to do something to get the speed of the two gears turning the correct speed to mesh. After pushing in the clutch and moving the shifter, you let the clutch out so the gears had a chance to spin the other gear up a bit then push the clutch back in a bit and then let it out again to bring the gear speeds together. Between the two clutch engagements you blipped the gas as necessary to help match the gear speeds. So, you used the clutch twice to make a shift. Watch the Bullitt chase. Bullitt does some downshifting in the hills and upshifting in the final chase.
I hope this helps.

 

More info. I have been a powertrain engineer for 50 yrs, so I geek out on this stuff so bear with me.
I try to just present data so here goes.
The heal/toe is generally toe on the gas and heal of the same foot on the brake. The other foot is on the clutch. The reason is to make smooth downshifts, save the clutch disk and keep the tires from breaking traction. The Auto Rev Match replaces the “toe” part of this work.

With the Auto Rev Match on.
This all works with a lot of magic going on. Down in the trany/shifter are a few sensors. These tell the computer what gear you just came out of and what gear you are going into. It senses when you come out of gear gate to neutral and when you move the shifter to the new shift gate area. If you shift slow you can hear two engine blips one for coming out of the gear and one when you start to put it into a gate/gear. This info is sent to the engine computer.

Next the real work starts. The engine knows eng speed, vehicle speed, gear out and gear in rotation. It also controls TB position, valve timing, fuel. It has a number of look up tables it goes to for a number of other parameters, torque and misc others. So when down-shifted quickly it takes the engine speed to the proper rpm for that gear/vehicle condition. It does that using these other measured and controlled eng parameters. So the eng rev is not just a blip but a very well calculated eng condition to make the best match for all the parameters. If shifting slow then it may sound like just a blip.
I pulled up my Z06 gear charts. A typical downshift I do is a 4th to 3rd gear shift with hard braking. I target about 3000RPM . This is no more than a 500 rpm mis match in engine speed. My downshifts take about .2 sec or less. This is about 10 engine revolutions. So with the use of Auto Rev Match the engine might see as many as 10 revolutions during the shift and likely fewer. And the speed of the engine is in the band where it is meant to produce the correct power (timing& fuel are all adjusted properly). These calculations happen between 50 and 400 times a second. The engine is not over revving or over working it is controlled to the speed it needs to be. It is in its happy spot for that shift.

Now if one does not use rev matching or a toe blip, the clutch & synchro must take the hit for these engine rotations until the 500rpm mis match in speed becomes close enough to stop clutch slipping. This generates heat in the clutch, extra wear on the synchronizers, and sometimes a bit of gear clunk. One way or the other the engine speed must match the vehicle speed conditions.
If shifting slowly the computer can not predict just how slow or fast you push the gear selector into the final position so it may have the eng revs drop off slower than desired- sometimes called engine hang. This is what many don’t like about the Auto Rev Match.

I hope this might shed a bit of light on the matter.

Ok and now double clutching: For up shifting or down shifting. There are a few different names for this and a few methods but in general the following is the general idea.

This method is used with older manual tranys that did not have synchros or the synchros were not very good. So what a synchro does is synchronize the speed of the input gear to the speed of the output gear it needs to engage with. Gear teeth have to match or they grind very badly. So, if you just pushed in the clutch and shifted up a gear, one of the gears was not turning the proper number of revs. So, an angled ring is placed on the gear shaft to slip into the gear to help bring it up to speed so as not to grind the gears this piece is the synchro. If this was not present or not working good enough when you shifted then you needed to do something to get the speed of the two gears turning the correct speed to mesh. After pushing in the clutch and moving the shifter, you let the clutch out so the gears had a chance to spin the other gear up a bit then push the clutch back in a bit and then let it out again to bring the gear speeds together. Between the two clutch engagements you blipped the gas as necessary to help match the gear speeds. So, you used the clutch twice to make a shift. Watch the Bullitt chase. Bullitt does some downshifting in the hills and upshifting in the final chase.
I hope this helps.

Thank you! I really appreciate your input.

 

I rev match 100% of the time, AND I track my car several times a year as well. BG888 provides a great explanation and OMG provides science behind it instead of fiction. It saves on my clutch during high speed downshifts and doesn’t jolt or shock the drivetrain.

 

its annoying alot of the times!!!....I doo not believe it helps the clutch at all...in a Laguna seca style like race..probably wood help.

 

I always use Rev Match - it makes up and down shifts so much better.

 

RevMatch doesn't affect upshifts

 

Not true. See page 195 of the owners manual where it specifically says it affects both. Plus, driving it in that mode is a noticable difference in both up and down shifts.

 

Trust me, unless you are tracking your car at 100+ MPH, RevMAtch has no noticeable affect on up shifts.

 

Uh huh. I've only owned and driven my M7 for 9.5 years. It makes a difference. If you don't want to use it, don't.

 

Set it every drive. Best sound when it down shift.

 

I've also had mine for over 9.5 years. You can't tell me you drive it hard enough on the streets to notice a difference when up shifting. It simply doesn't affect it. Now, downshifting is a whole different story. It will blip 100% of the time. But never on up shifting.

 

It doesn't blip on up-shifts, it's not how the system works. First you said the system only works on downshifts, then when I corrected you with the manual you changed to it only works in high performance track type driving... You're wrong and have exposed yourself as not knowing what you're taking about.

 

Trust me, it does not work on up shifts. There is no need to match revs on up shifts. No need at all. As far as changing my stance, it was just poor choice of words on my part. I know 100% what I am taking about. As I have tracked my Z06 many times, and tested specifically to see if it Rev matched on upshifts, and it does NOT. So, keep telling yourself you notice an upshift difference in your Stingray, and keep enjoying it.

 

Just a bit more info.
When upshifting there is a mismatch in speed in each gear shift. For example, revving out to 6500rpm and then shifting up requires a drop in engine speed of aprox. 1500rpm at the completion of the shift depending on trany and gear set. The clutch will take most of the hit in slip as it is let out. The engine speed needs to drop fast enough to help, or the clutch will take the burden of slip to match the speed. In some cases, the tires slip but this is after the clutch has connected to pass the torque or while it is slipping and passing torque. Regardless of where it happens because it is a mechanically connected system (no torque converter to slip) the system must match speed. On road racing tracks the shifts are typically not as fast as at a dragstrip. For drag racing generally the clutch is going to be slipped and the driver will deliberately let the clutch take abuse to get the fastest times. In extreme cases this is called a no lift shift (the throttle is not let up for the shift). For road racing and for normal driving, shifting is not done this way. So, it is imperative that the engine speed drops to the new required rpm before or as the shift is completed. Some engines drop rpm faster than others and some hang and don’t drop very fast. For fastest acceleration you may want the engine speed higher than the match speed to use some of the rotational energy as well as the engine producing more power at the higher rpm, but when the clutch is engaged something needs to give so that all the proper speeds are obtained. In the lower gears the tires spin, in higher gears the clutch slips. On a drag strip this occurs maybe 4 times on a normal pass but on a road track this could happen many multiple times each lap, so to take care of the clutch a matched shift is better.
My understanding is that the ARM sets the TB position to help get the engine to the proper rpm. In many cases during an upshift the difference in speed is not that much and the shift speed is such that the engine may drop enough in rpm as well as a bit of rpm difference is absorbed during the shift to use the kinetic energy, so you may not notice much action. So, the ARM is working but you may not notice because your shift did not require intervention. I do feel a difference at intermediate rpms, not so much on low rpm shifts, but using the ARM reduces the torque bump I get from the rotational inertia due to a rotational speed mismatch.
Hope this helps

 

Thank you for your input.

 

I dont know what the technical details are on the Rev Match system but up-shifts are noticeably smoother with the system engaged.

 

I have noticed that shifts are smoother with the system engaged too.