Can you hold the gas while downshift revmatching?

[Transvestor]

Can you hold hold gas while downshift revmatching instead of blipping? Does holding the gas instead of blipping cause more wear on the clutch and syncros when downshift revmatching?

I feel more comfortable holding the gas instead of blipping.

[potownrob]

Can you hold hold gas while downshift revmatching instead of blipping? Does holding the gas instead of blipping cause more wear on the clutch and syncros when downshift revmatching?

I feel more comfortable holding the gas instead of blipping.

do you mean you push the clutch in and then gas it while moving the stick and let off the gas while letting out the clutch in the lower gear?? that sounds alright as long as you're not having trouble moving the shifter between gears when you do this. if you're, holding down the gas before and/or after pressing in the clutch and letting it out in the lower gear, you're probably asking for problems though.

[Transvestor]

Can you hold hold gas while downshift revmatching instead of blipping? Does holding the gas instead of blipping cause more wear on the clutch and syncros when downshift revmatching?

I feel more comfortable holding the gas instead of blipping.

do you mean you push the clutch in and then gas it while moving the stick and let off the gas while letting out the clutch in the lower gear?? that sounds alright as long as you're not having trouble moving the shifter between gears when you do this. if you're, holding down the gas before and/or after pressing in the clutch and letting it out in the lower gear, you're probably asking for problems though.

Yeah that's what I mean. After raising the revs I promptly remove my foot off the throttle completely before I go to engage the clutch and add gas if needed to maintain the car speed. I just wanted to confirm that raising the engine revs by holding down the gas was just as safe to vehicle as is blipping the throttle.

After reading your response I also have another question:

Do I need to remove my foot off the throttle completely before engaging the clutch or can I slowly release the throttle and engage the clutch simultaneously(as you described)?

[potownrob]

Can you hold hold gas while downshift revmatching instead of blipping? Does holding the gas instead of blipping cause more wear on the clutch and syncros when downshift revmatching?

I feel more comfortable holding the gas instead of blipping.

do you mean you push the clutch in and then gas it while moving the stick and let off the gas while letting out the clutch in the lower gear?? that sounds alright as long as you're not having trouble moving the shifter between gears when you do this. if you're, holding down the gas before and/or after pressing in the clutch and letting it out in the lower gear, you're probably asking for problems though.

Yeah that's what I mean. After raising the revs I promptly remove my foot off the throttle completely before I go to engage the clutch and add gas if needed to maintain the car speed. I just wanted to confirm that raising the engine revs by holding down the gas was just as safe to vehicle as is blipping the throttle.

i forget the term for that, but that is a known and accepted method of rev-matching, unless i missed something.

After reading your response I also have another question:

Do I need to remove my foot off the throttle completely before engaging the clutch or can I slowly release the throttle and engage the clutch simultaneously(as you described)?

i don't think you have to, but you can cause damage if you don't let off the gas. remember that the purpose of rev-matched shifts are to match up the speeds of the engine and transmission (put very simply); the transmission can pull down the revs upon letting out the clutch, if the engine's spinning too fast, during a proper downshift; if you have your foot on the gas, the transmission will NOT be able to pull down the revs past where you have them set with your right foot...

[Transvestor]

Thanks for the help and clarification Potownrob. If anyone has *anything else to add or reconfirm please do so.

[potownrob]

Thanks for the help and clarification Potownrob. If anyone has anyone else has anything to add or reconfirm please do so.

no problem. you'll probably get better and more technical replies during the day; lots of engineers and mechanically knowledgeable people in here.

[Boston Fit]

Normally, I do not come completely off the gas when shifting. Instead, I try to keep revs in the target range for my next gear. For example, when going from 2 to 3, as I am clutching and shifting, my right foot remains on the gas pedal such that RPMs are where I will need them to be for 3rd gear. That means I am (slightly) reducing throttle pressure enough to let the the RPMs decrease a little, without completely releasing because that would cause RPMs to drop too quickly. If I were downshifting from 3 to 2, I would do the opposite and give it a bit more gas so as to increase RPMs into the 2nd gear range.

It took me a little while to get that technique down, but now it's second nature.

Hope that helps.

[daleadbull]

When the clutch is down, you can blip or hold it steady or tap dance on it or whatever else you want. But I think what your asking is if its ok to hold the gas at the correct RPM while letting off the clutch, correct?

I personally don't do this but I've read that this "steady RPM" rev match is acceptable and many people do it. I myself prefer to just blip to the right RPM then engage the clutch while giving almost no gas. This way I know I'm not burning the clutch and if the rev match is close then it should be smooth and I wouldn't have to give it gas till the clutch is fully engaged.

[Krimsalt]

Usually it's not wise to hold the gas as you let off the clutch when downshifting. It's putting to much pressure on the engine mounts/output shafts. Best to blip it to the proper RPM or a little higher depedning how quick you let out the clutch

[RITmusic2k]

Sorry, but the above is absolutely wrong.

The only thing -- the ONLY thing -- that causes wear on the clutch is if it is spinning at a different rate than the flywheel when the two come together. It makes no difference whether the difference in RPMs comes from too much throttle, too little throttle, or too much change in vehicular speed, or anything else.

Remember that when the car is fully in gear and moving forward, that everything in the system is mechanically locked. That means that for a specific gear and a specific vehicle speed, there is only one possible engine speed to observe. The act of rev-matching is designed to get the engine to whatever RPMs it will be turning at when the clutch is released and the system is coupled back together.

Imagine that your car is cruising in top gear at a steady 65mph. The engine speed is 2,500rpms. Let's say you press the clutch in and take your foot off the gas pedal just as the car comes to a slight decline. You're now effectively in neutral (hell, you could shift into neutral and take your foot back off the clutch), and the car is continuing to coast at 65mph. You eventually decide that you want to get back into top gear. The car is still moving at 65mph. You press the clutch pedal back in, move the gearshift to top gear, and:

(1) blip the throttle up to 2,500rpms and then immediately release the clutch pedal

(2) blip the throttle up to 3,000rpms and then 'catch' the engine by releasing the clutch pedal as the revs descend down to 2,500

(3) gradually raise the throttle up to 2,500rpms, hold it there with partial throttle and make sure you're definitely at 2,500rpms, and release the clutch as quickly or as slowly as you like

(4) use any of the above methods, but over- or undershoot wildly... recognize your mistake, let the engine speed drop back to idle with the clutch still held in, try again and again until you get it right, and then release the clutch pedal


As long as the car was still traveling at 65mph, and the engine revs were exactly at 2,500rpms at the time the clutch re-engaged, then in each of the above scenarios you've incurred the exact same amount of clutch wear, which is essentially zero. The only difference between blipping and catching revs and holding revs steady is that you need better timing and awareness of your clutch pedal's friction point when catching changing engine revs. Timing isn't important if vehicle speed and engine speed are steady when releasing the clutch.

So in practice, as long as you're aware of the correct engine speed for your current vehicle speed and gear choice, holding revs steady is actually the easiest way to minimize clutch wear while shifting into gear.

[Shadow]

Normally, I do not come completely off the gas when shifting. Instead, I try to keep revs in the target range for my next gear. For example, when going from 2 to 3, as I am clutching and shifting, my right foot remains on the gas pedal such that RPMs are where I will need them to be for 3rd gear. That means I am (slightly) reducing throttle pressure enough to let the the RPMs decrease a little, without completely releasing because that would cause RPMs to drop too quickly. If I were downshifting from 3 to 2, I would do the opposite and give it a bit more gas so as to increase RPMs into the 2nd gear range.

It took me a little while to get that technique down, but now it's second nature.

Hope that helps.

If your RPMs drop too fast while upshifting, you're shifting too slow. You really shouldn't have to use any throttle at all when shifting into the next higher gear. And if you have a car with rev hang (and a lot of new cars have it!), then you should have even less of a problem with the RPM falling too fast. Try speeding your shifting up a bit and you'll probably find it much more enjoyable.

[Boston Fit]

The "steady RPM" rev match technique as daleadbull describes it (and further explained in RITmusic2k's post) is what I must be doing, though I did not know it by that name.

[daleadbull]

If your RPMs drop too fast while upshifting, you're shifting too slow. You really shouldn't have to use any throttle at all when shifting into the next higher gear. And if you have a car with rev hang (and a lot of new cars have it!), then you should have even less of a problem with the RPM falling too fast. Try speeding your shifting up a bit and you'll probably find it much more enjoyable.

I don't think that's always the case. I believe that sometimes the revs can drop extremely quickly. For example, when my engine is cold my revs drop like a ton of bricks. So in order to shift smoothly at lower rpms I need to be really quick with engaging the next gear with the clutch while give a tiny amount of gas during the shift. In my case, this only happens for the first few minutes after a cold start. So who knows, maybe in his car the revs drop that fast all the time.

[Squint]

Back to OP's question - yes. You can do a "steady" rev match and be just fine.

I tried the blipping method when I was learning - just giving the gas a quick tap when changing gears - and I never did very well with it. So I switched to the "steady" method which just means that I'm putting my foot down and giving it some RPM while I'm getting into x gear. It goes something like...

- push clutch in, foot off gas pedal for a brief moment
- shift to appropriate gear
- as I'm putting the car into gear, I increase RPM to approximate levels required by the gear
- clutch out, usually fairly well matched shift

That was a single clutch shift, you can do the same thing with a double clutch if that is more of your thing.

[rml605]

I always do the blip. Just less room for error at least in my case. I would always rev the heck out of my car if I held it steady. I guess if you're quick and nail the rev match, you should be fine. I've never been in a situation like this, but if I was ever on the highway in a desperate need to get over to an exit and need to DS as quick as possible from let's say, 6-4, i'd probably just hold the gas and go.