As I already asked in topic title - does anyone know what is manufacturers recomendation for optimal RPM for 1.4 MPI. I assume that this is between 2000-2500 RPM but I'm not sure. According to board computer, it looks like optimal fuel comsumption is when engine is runing around 2000 RPM. On the other side, I know that some benzine engines like to be driven in high RPM ratios.
So, does anyone know the right answer to this question?

Thanks,
Igor.

For fuel consumption, the lower the RPM, the better. But if it is too low, it will start to consume oil, too AFAIK 2000 rpm is quite ok (low consumption but you don't kill the engine)

taxi drivers here use to run on low RPM's; I aslo guess 2000 is quite all right;

yes but they also do a revision every half-year i think.. right? and they also tweak their cars every now and then so everything runs smooth...

I've just read this topic about optimal RPM.
First I want to mention that I haven't a Logan,
I have a Solenza but with 1.4 MPI engine (from Clio2).
I've discussed this problem with many collegues and the conclusions are:
- for cruise speed around 2500 rpm
- for "gear up" - 3000 rpm
- for "gear down" - 2000 rpm

There is no such a thing like "optimal rpm"... so, the manufacturer not recomand anything.... BUT.... if you use to drive ar rpm'a around the maximum torque (is between 2800 and 3500 rpm), you will obtain lower consumption averages...

P.S. usually when you ask for an "optimum", you should explain what is your objective/acope/aim!... what you want to minimize or maximize... in this case I assumed you want to obtain a minimum for the fuel consumption!

This question came to my mind because I saw that some other manufacturers state in car user manuals speed limits for each gear (lowest and highest). This means that driver should not drive (at least not for a longer period) above nor below recomended gear speed limit. When you translate this to RPM you get optimal RPM range. I always asumed that somewhere in the middle of that RPM range is optimal RPM where fuel consumption, oil consumption, overal engine performance and durability are best balanced. Of course, this is theory... In the real life it is impossible to drive car on constant RPM. I started this topic hoping that someone will post manufacturers recomendation regarding gear-speed-limits/rpm-ratios...

Anyway, this is not a big deal - it's just my curiosity.

OK I get your point!

The rpm optimum range described by you is for reliability purposes... and another range is arround the optimum consumption rpm values.

For Dacia it is not necessary to show the uper limit ... the rpm is electronically limited by the computer (6200 for 1,4 mpi engine) ... the lower one, hmmm... by experience I recomand you to not use frecvently < 1500-1800 rpm's (except for 1st gear and reverse, of course).

I agree with AL on this one: it makes no sense to drive under 2000 RPM (the actual value depends on road conditions like ramp...). I noticed that if you accelerate in a gear from 1500 RPM you get the same fuel consumption as in a lower gear but with a more adequate RPM (~2500) for the engine.

About the lower limit, it is dependent by the charge. If you are stopped, the engine has about 800-900 rpm and can run for hours without any problem. At lower speed in 1st or 2nd gear you can have 1000-1500 rpm.
By the other hand, going up on a slope with 2000 rpm in 5th gear is not good for the engine, is better to go in 4th gear with 3000 rpm or even with 4500 rpm in 3rd gear if you want to acccelerate.

cool down!.... he asked about what Dacia recomand!... this topic is not about how to use the rpm range when you drive!!!!

The only recommendation from Dacia related to rpm is to not exceed 3000 rpm in the first 1000 km after the new car has been bought.
And I suspect no other manufacturer specify that kind of limits, we are talking about.

I think it has 750 RPM in neutral.

Could be 750 rpm without any consumer. Using AC, lights, extra consumer plugged in the lighter socket and so on, will increase the value.

after starting a COLD engine, rpm goes around 1100 ( it is a warming-UP state (na srpskom SAUH))

after warming on a neutral speed, engine goes around 500-600 rpm. Just notice , when you get engine on neutral, EVERY larger electric consumer (lights,rear glas warmer, electric fan or even electric glas mover (on a front doors)) will put rpm down (on a 400-350) for 1-2 seconds because it uses power from alternator. after 1-2 seconds electronic in engine will automaticly raise up rpm on a 500-600.

It's more like 760 rpm. Watch carefully.

Definitly 600

Don't think so. Again:



The first line is 500

yess,my mistake, i did not pay attention on a first line. it is 500 , not 0



you have blue lights n background? which model do you have?

The colour of the lights is orange for all versions. But he modified his lights, not the manufacturer.

nice look `n`feel

Watch carefully
Staying still, one actually goes 10 kmph ( + the speed of Mother Earth )