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Difference between Bluehdi 100 and 120

15K views 13 replies 6 participants last post by  Softrider 
#1 ·
Hello everyone! As mentioned on theme my question is whether there is a difference between bluehdi 100 and bluehdi 120 engines or not. Besides of course of the engine programm. Do they share exactly the same mechanical parts such turbo?
 
#2 ·
The first difference is the HDi 120 models are all 6-speed to cope with the increased torque which the 5-speed in the HDi 100 isn't rated for. The next difference is the HDi 100 has a fixed-vane turbo where as the 120 has a variable geometry turbo, plus there are other less important changes. A variable vane turbo allows the angle of the blades to change to shallow (which means a better reaction at low revs) to steep (which means more 'push' at higher revs)
 
#3 ·
Thank you for the reply. This was very analytic information about the differences of the two engines.
As an owner of a Cactus feel edition bluehdi 100 I have some thoughts for engine reprogramming. Winning about 30% of power as I feel as a car and as a chasis it deserves a little more power.

I would love to hear experiences and opinions!
 
#4 ·
We drove a Peugeot 308 SW HDi 120 in our summer holiday.
WAY more powerfull engine combined with the six speed.
 
#5 ·
The highways is not the best for my cactus as if you want to move fast the consumption is higher even from the city use... It's because of the five gears and of the lack of power. Though when I am on countryside it's like a fish in the water! No matter of the bad road surface and the consumption is about 3.6 to 4. It's something incredible! The point is that we can't have it all... In general terms I am very pleased so far by the car accounting it's price too!
 
#6 ·
Don't get too caught up on the 6-speed v 5-speed gearbox; 6th gear in the 6-speed 'box is very close to 5th in the 5-speed 'box, it is the intermediate ratios that are closer rather than 6th being an overdrive. For example, 4th in the Cactus is too tall to drive around at 30mph unless on the complete flat, with the 6-speed 'box 4th is perfect for town driving.

You can remap a 100, the gains are there.
 
#8 ·
geokaps2005 said:
Do we know how much torque can the 5 gear box can handle?
A torque characteristic I have seen for the Bluehdi 100 engine is max torque of about 255 Nm at engine speed of 1750 rpm, falling to 175 Nm close to 4000rpm.

For the 120 engine the torque figure rises to 300 Nm at 1750 rpm, falling to 210 Nm at 4000 rpm.
 
#10 ·
I was thinking as I mentioned above of having a reprogramming of the ECU order to gain more power. About 30%. Though I am considering it, as I don't know how much torque my gear box can tolerate. If it can handle about 30 kgm it would be perfect!
Here is an example:
 

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#12 ·
The PSA 5-speed gearbox in the Cactus BlueHDi 100 is not a sophisticated gearbox, but it's significantly better when the car has run 50-60000 Km (about 35000 Miles). The PSA 6-speed gearbox in, for example, the C5 with the 2.0-liter HDI engine is very good and, in my opinion, better than the BMW's equivalent 6-speed gearbox in the F30 320d (and it says quite a bit)

I do not know how much torque the current PSA 5-speed gearbox can withstand without knowing what it's called internally at PSA, but it's not the gear ratios or the final drive ratio that is the challenge if you want more horsepower. The car has an extremely high gear ratio and, for example, the engine has no more than aprox 1700 rpm at 100 Km/h (62 mph) in fifth gear. The engine's maximum torque of 254 Nm (187 ft-lb) is developed at 1750 rpm. Maximum power of 100 horsepower is developed at 3750 rpm.
 
#14 ·
You can calculate engine rpm vs. gear ratio by using the following formula (metric units - except for the size of the tires that are still stated in inches for some reason): rpm = (km/h x gearbox ratio x rear axle ratio x 5305) / ((25.4 x tire size) + (2 x tire width x tire profile))

For my Cactus BlueHDi 100 that has 195/65-15 wheels, the formula becomes at 100 Km/h in fifth gear:
rpm = (100 x 0.58 x 3.47 x 5305) / ((25.4 x 15) + (2 x 195 x 0.65))
rpm ≈ 1683
 
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