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#84
09-08-06, 18:11
The 155 Q4 maximum boost is usually stated as 0.85 bar and over-boost (shorter period of time) is said to be 1.1 bar.

So are the official power/torque figures given at stationay 0.85 bar boost or at temporary 1.1 bar boost?

(I realise that those boost pressures figures has more to do with maximum torque than with maximum power)

Steve Webb
10-08-06, 12:39
I'd guess that the figures were taken whilst the overboost was operational so as to give a higher figure. Don't know this for certain, but all car manufacturers like to portray their cars in the best possible light don't they? Have you noticed that most car manufacturers make it possible to do just over 62mph/100kph in second gear, just so the 0-62(100) times look good?

Steve

#84
10-08-06, 18:19
In a way it soounds reasonable what you say. Probably the car manufactures does not follow any ISO-standard for official engine ratings.

However, I made a simpel calculation based on Evocars Hybrid chip for Evo2. If the Evo 2 also has a rated boost of 0.85 bar you get 310 Nm * (1,35+1)/(0,85+1) = 394 Nm. Rated torque with this chip is 393 Nm @ 1,35 bar. So, that speaks against your theory, but I haven't checked the linearity of bosot v.s. torque with the books.

- And yes I have noticed how the car manufacturers choose the gear ratio to get a perfect 0-100 time. I suppose that was how the orginal Scooby GT managed to do 100 km/h cöose to 6.0 s. Audi has also very good 0-100 figures, but they are not very inspiring and does not feel that fast. Saab does not match it that good and has terrible 0-100 figures despite powerful engines. I thought about swithsching the 210 hp 9-3 for a A4 Sport Quattro top get betetr acceleration and 4wd, but I was really dissapointed. Fwd Saab was much better tight bends than the 4wd Audi....

A bit off the thread :D