when to shift the gears?

[elaasi]

Hi guys, 

 

Not long ago I've purchased my first car, it's a 2004 (2005) Skoda Fabia with a 1.9 TDI ATD (74 kW, 99 HP) engine with 400k km. And I am not that much of a driver, one of my friends, recommended that I **** the gears at around 2k no more than 2.5k RPM, cause as he said if I go more than 2.5k RPM it will start (include) the turbo, and he said that I don't really want that. Now...I mostly drive in the city, I am not a speeder or smth, as it is my first car and I don't have that much experience in driving, I try to drive as safe and by the rules as I can. And for 3-4 months, I was doing so everything good, and I was reading some posts on how to improve my driving skills, from the shifting gear point of view, and some people with the same 1.9 TDI engine, were saying that I must never shift under 2.5k RPM and that the most recommended would be 3k - 3.5k RPM. For me, at 3.5k the engine sounds a little too loud, and kind of struggles, but as I am a newbie I don't really trust myself. But I kind of trust this forum as it helped me with all the issues that I have had until now. So guys what are your recommendations, how do you do? 

[valvedoctor46]

Hi elaasi, If your car has a turbo fitted, I cant understand for a minute why your friend wants you to drive it without the turbo kicking in. Seems bizarre!!!

[JWvrs25]

Depends very much on the road conditions and required acceleration. In a diesel you can use the low end torque for normal driving, but don't keep it in too high of a gear when maintaining or accelerating as youll be labouring the engine which isn't good.

You'll eventually get used to driving it and find out what works best, there is no set rules for when to change, but certainly shifting at 3.5k for normal driving is not necessary.

 

In a diesel you are using the turbo almost all the time unless very low revs (>1400rpm)

[elaasi]

4 minutes ago, valvedoctor46 said:

Hi elaasi, If your car has a turbo fitted, I cant understand for a minute why your friend wants you to drive it without the turbo kicking in. Seems bizarre!!!

hi, I don't know, didn't ask at that time, but yeah, even though he has more experience he is still a fellow student, so not that much, but I don't know why he recommended so )) 

[elaasi]

4 minutes ago, JWvrs25 said:

Depends very much on the road conditions and required acceleration. In a diesel you can use the low end torque for normal driving, but don't keep it in too high of a gear when maintaining or accelerating as youll be labouring the engine which isn't good.

You'll eventually get used to driving it and find out what works best, there is no set rules for when to change, but certainly shifting at 3.5k for normal driving is not necessary.

 

In a diesel you are using the turbo almost all the time unless very low revs (>1400rpm)

Well, the road conditions are fine, there is no snow or ice, the traffic is rather lite, but as I said I do not overaccelerate, just normal driving, maybe sometimes when it is necessary (that's when I would go over 2.5k) but as I said, as I feel the engine and sound I kind of think that at 3k it's overstressing... 

 

About the Turbo, I guess that friend was wrong :)) 

 

But thanks for the reply, I am going to drive the same way as I was driving until now :)) 

[JWvrs25]

1 minute ago, elaasi said:

Well, the road conditions are fine, there is no snow or ice, the traffic is rather lite, but as I said I do not overaccelerate, just normal driving, maybe sometimes when it is necessary (that's when I would go over 2.5k) but as I said, as I feel the engine and sound I kind of think that at 3k it's overstressing... 

 

About the Turbo, I guess that friend was wrong :)) 

 

But thanks for the reply, I am going to drive the same way as I was driving until now :)) 

By road conditions i mean what speeds would be required i.e fast highway type road or quiet housing estate.

You wont be over-stressing anything by hitting 3k, just wasting fuel. 

Driving at low revs all the time will eventually cause issues somewhere due to the soot build up in the engine and turbo being an old diesel, so good to give it a quick run up past 3.5k every now and again to keep it clear.

[elaasi]

1 minute ago, JWvrs25 said:

By road conditions i mean what speeds would be required i.e fast highway type road or quiet housing estate.

You wont be over-stressing anything by hitting 3k, just wasting fuel. 

Driving at low revs all the time will eventually cause issues somewhere due to the soot build up in the engine and turbo being an old diesel, so good to give it a quick run up past 3.5k every now and again to keep it clear.

oh ok, so when you say low rev you mean 2k-2.5k shifting RPM? as I said I mostly drive in the city, so city driving condition under 60-70 km/h, and from now and there I do run it up to 3.5k when it is needed but not on normal basis 

[JWvrs25]

Low revs being 1000-1500 which is not a particularly good range to be driving in all the time

[elaasi]

ok, I understand, I do usually go to 1.5k when I am normally driving and up shifting....will try to rev it up a little, thanks...aaand sorry that it was needed to extraexplain, as I said I am still a newbie

 

Edited 24 January, 2018 by elaasi

[KenONeill]

@elaasi - Your friend is talking nonsense. The 1.9TDi starts boosting at about 1_200rpm, reaches full boost pressure at about 1_500, peak torque at about 1_850, and peak power at 4_000. You can't over-rev it because it has a soft governor that will stop it revving higher at about 4_600.

 

If you are desperate to "save fuel" change up at about 1_500, but it's much more brisk to drive without using much more fuel if you rev to about 2_100, when a change up drops back to 1_600, so you're using peak torque as much as possible.

[elaasi]

1 minute ago, KenONeill said:

@elaasi - Your friend is talking nonsense. The 1.9TDi starts boosting at about 1_200rpm, reaches full boost pressure at about 1_500, peak torque at about 1_850, and peak power at 4_000. You can't over-rev it because it has a soft governor that will stop it revving higher at about 4_600.

 

If you are desperate to "save fuel" change up at about 1_500, but it's much more brisk to drive without using much more fuel if you rev to about 2_100, when a change up drops back to 1_600, so you're using peak torque as much as possible.

Hi mate, 

 

I am not looking necessarily to save fuel, I am just trying to be a better driver, and do what is best for me, for the car and for the road (other drivers). Thanks for the advice,  it's very nice to get this in-depth information as it is much easier to understand the car. 

[JWvrs25]

When you say 'better driver', what do you mean?

Surely in this case it would be to use least amount of fuel possible whilst maintaining good progress as above stated.

 

I think the answer has to be drive it more and you will gain the experience how to get the most from the car and what works in different situations. Same logic that applies when you replace the car and have to get used to a different one all over again.

 

 

[elaasi]

On 24/01/2018 at 15:23, JWvrs25 said:

When you say 'better driver', what do you mean?

Surely in this case it would be to use least amount of fuel possible whilst maintaining good progress as above stated.

 

I think the answer has to be drive it more and you will gain the experience how to get the most from the car and what works in different situations. Same logic that applies when you replace the car and have to get used to a different one all over again.

 

 

As I have been driving it for a while, I can say that your answer makes sense now, and my question seems kind of stupid :)) but we all have to learn. In any case thanks a lot!

[VWD]

I find it depends on mood. A lot of time, I just pooter around old man fashion, but I find that low rev changing and letting the torque talk can get a spritely performance way above that which the figurs suggest. Personally after a lot ( 50)of years on the road and driving almost all my licence allowed me to drive , I've found that engines will talk to you( ifyou are prepared to listen) and tell you when they are happy.