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yup, blip on downchange to smooth not up.
Anyone else dab the gas on an upshift?
- Thread starter Ken
- Start date
Mr Jack said:
Engine speeds in diesels will drop quicker, mostly due to being much higher compression than petrol motors. That said, I can still change gear in Dad's Panda without having to dick about with the go-faster pedal, so either the OP is shifting very slowly indeed or his car maybe has an issue.
Last edited:
Soldato
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When I read "I can't stand unsmooth gear changes whether I'm the driver or passenger." I immediately thought 
, but without the hat.
, but without the hat.
If cruising along at 30, I can stick mine into 5th and it can still roll smoothly without lugging the engine. 
What I do is, after I change gear, I kind of drop the clutch to the biting point, pause it for a split second which will allow the cutch/flywheel to sync, then fully release and apply the gas. By split second, I really do mean that, and I always get smooth changes, up or down.
What I do is, after I change gear, I kind of drop the clutch to the biting point, pause it for a split second which will allow the cutch/flywheel to sync, then fully release and apply the gas. By split second, I really do mean that, and I always get smooth changes, up or down.
Soldato
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Quite a lot of the time, I usually 'power shift' in my diesel by not letting fully go of the gas pedal, not so much that it screams inbetween gears, but enough to that the revs don't die totally down. The gearing in my car is approx 1500rpm between gears, so if I change at 4K RPM in third to 4th, the revs will drop down to about 2.5 which is just nicely in the power band to accelerate. Likewise with 2nd to 3rd.
This also makes it a piece of cake to rev match on the downshift. which makes for smoother driving. I usally do it in the lazy manner mentioned above - I just don't take my foot fully of the gas.
This also makes it a piece of cake to rev match on the downshift. which makes for smoother driving. I usally do it in the lazy manner mentioned above - I just don't take my foot fully of the gas.
If I'm doing a slow lazy upshift, I'll just let off the gas about half way so the revs drop slowly, then I come off the clutch when the revs match the speed. If I'm going quicker, the engine can pull the revs down and the clutch can take the stick...
I think when he said upshift, he meant downshift..
You clearly aren't driving the most economically with how you describe. As a general guide, peak economy is at peak torque in each gear. If you're in 4th at 28mph, you'll be no where near peak torque, thus using more fuel then necessary and possibly labouring the engine.
Also, flooring it to 45mph in 3rd is pointless too - if you want to build speed, keep accelerating in 2nd or 3rd up to peak power and then change.
You clearly aren't driving the most economically with how you describe. As a general guide, peak economy is at peak torque in each gear. If you're in 4th at 28mph, you'll be no where near peak torque, thus using more fuel then necessary and possibly labouring the engine.
Also, flooring it to 45mph in 3rd is pointless too - if you want to build speed, keep accelerating in 2nd or 3rd up to peak power and then change.
Usually when I'm bored.
Soldato
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You shouldn't need to mess with the throttle when changing up. Just learn to drive, or trade in your licence for an automatic one.
I use the throttle when downshifting to overtake, or braking (heel n' toe), it's quite easy with practice.
I use the throttle when downshifting to overtake, or braking (heel n' toe), it's quite easy with practice.
How does it make it smoother? Surely it'd make it worse unless the shift took so long that the revs fell below what they would be when the next gear was engaged (in which case a quick blip of the throttle could help match the revs again for when the clutch is let out)
commited said:
If you floored it in 2nd at 45mph in the ops car you would hit the redline very quickly indeed mainly because its a diesel (VAG 2.0TDI) and will be turning 4000+rpm at 45mph in 2nd anyway. Thus sticking it in 3rd and flooring it is the best option.