Are bad gear changes more noticeable in a tripot engine?

[fourthpedal]

Or is it just my technique?

I usually have no issues with smooth downshift, and I'm, following the Local technique for rev matching - but it can fall apart when I'm rushing myself, or I'm in the mountains (usually both at the same time). I've only done 7000 miles since my test mind you. Since I've never driven a manual with more than 3 cylinders, I'm curious whether you had an easier time shifting in older more powerful cars.

Edited by fourthpedal on Sunday 26th January 18:13

[brisel]

I've found that bigger engines with more inertia/momentum will be easier to let you know when your rev matching was wrong. My last 2 cars were a 6.2 and a 4.2 litre block.

Do you find it worse on upshifting or downshifting? I find rev matching quite slow - Great for downshifting going up a hill as you just let the revs rise with a bit of right pedal as you change. I mostly blip the throttle for downshifts. Practice makes perfect.

Edited by brisel on Monday 27th January 20:03

[ATG]

"Let you know" in a Chimaera can mean "have a go at spinning itself." It was years ago, but I still remember my foot slipping, leading to a huge dumped rev mismatch. It didn't break traction completely, but the tyres chirped and you could feel the car twist and load up around the rear wheel that was feeling the bulk of the torque. Made you fear for your life and the health of the car.

[Glosphil]

I don't have any trouble carrying out smooth gear changes in my wife's 2019 3-cyl 1.0TSi (110hp, 148lbft) Fabia.

[CanoeSniffer]

A free spinning engine will be easier to downshift with as a throttle ‘blip’ is required whereas a big heavy flywheel motor will take a moment to reach the desired rpm. After years on track in a Chimaera and racing Jags with big sixes and V8s I bought a little NA MX5 with a 1.6 and initially found myself overrevving every downshift as the revs were there so quickly! After some time adjusting I found the little engine to be a lot more satisfying to downshift in, much easier to be precise than with the big brutes where quite frequently (especially in a race where so many circumstances can adjust your line, braking and downshift approach and technique) the name of the game was just to mash any sort of inertia into the engine before giving it the gear, rather than precision rev matching and beautiful crisp changes which were easily achievable with the little sewing machine motor.

[ScoobyChris]

CanoeSniffer said:

A free spinning engine will be easier to downshift with as a throttle ‘blip’ is required whereas a big heavy flywheel motor will take a moment to reach the desired rpm.

This is true and conversely one of the challenges with a small engine/light flywheel is that the revs can fall quite quickly too so if you are not used to holding the revs as part of the change, you can find they can drop and you don’t get the smooth change. One interesting exercise is to find a quiet straight road and really slow the gear change down and see if you can still do it smoothly.

Chris

[fourthpedal]

Thanks all!

ScoobyChris said:

CanoeSniffer said:

A free spinning engine will be easier to downshift with as a throttle ‘blip’ is required whereas a big heavy flywheel motor will take a moment to reach the desired rpm.

This is true and conversely one of the challenges with a small engine/light flywheel is that the revs can fall quite quickly too so if you are not used to holding the revs as part of the change, you can find they can drop and you don’t get the smooth change. One interesting exercise is to find a quiet straight road and really slow the gear change down and see if you can still do it smoothly.

Chris

My issues are primarily on downshift - going by all the replies that clearly means that I'm doing something very wrong with my right foot. In my defence it _does_ feel like there's some lag in the throttle, and the engine is relatively quiet (it's hard to be sure what it's doing without looking at the tacho - and maybe my winter tyres are making the problem worse), but it might be as simple as my lack of patience.

Nothing for it but to get practicing - fortunately we have a lot of straight roads along the bottom of the mountain valleys round here, the only trouble is that they're rarely quiet.

[_Neal_]

fourthpedal said:

My issues are primarily on downshift - going by all the replies that clearly means that I'm doing something very wrong with my right foot. In my defence it _does_ feel like there's some lag in the throttle, and the engine is relatively quiet (it's hard to be sure what it's doing without looking at the tacho - and maybe my winter tyres are making the problem worse), but it might be as simple as my lack of patience.

Nothing for it but to get practicing - fortunately we have a lot of straight roads along the bottom of the mountain valleys round here, the only trouble is that they're rarely quiet.

Even if the roads are busy, changing from (say) 4th to 3rd, or 3rd to 2nd at a constant speed (say 30mph) is a decent test for rev matching, you'll be able to tell very easily if you've got it right. Can also try "blip" and sustained rev changes.

PS - ex-Chimaera owner here too, that car taught me a lot about rev matching!

[MikeM6]

I have found rev matching harder, but not impossible, in newer cars due to their laggy throttle mapping and rev hang. Lots of cars feel unnatural, so it takes a bit of time to figure out what is happening.

For many cars, smooth upshifts are night on impossible to do quickly as the revs do not drop for what feels like an age. Of course, some are better than others at this.

[bergclimber34]

Rev hang is such an awful thing in modern cars, especially cheaper stuff that I drive

[MikeM6]

bergclimber34 said:

Rev hang is such an awful thing in modern cars, especially cheaper stuff that I drive

Yep, I drive a lot of rental cars through work and I have to pick the small manual option. They are often both great and terrible at the same time, but the gearbox is always a weakness.