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Was doing some reading on the Giulietta QV and realized that the same engine in the QV has 235PS @ 5500rpm and 340Nm @ 1900rpm vs the 159's 200PS @ 5000 rpm and 320Nm @ 1400 rpm. This equates to a 6.8s time vs 7.7s for 0-60 mph times.

I can appreciate the fact that the 159 is abt 100 kg heavier but why didn't Alfa plant the QV engine into the final production run of the 159 or Brera? Would've been a real cracker!

Sadly, marketing gone wrong as usual :rolleyes:
 

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I think the numbers aren't as different as they appear..

reportedly, 159/Brera's dyno'd have come in at ~205bhp as standard, and the Guilietta at ~222bhp

The camshafts are different I think, hence the G's power and torque being a little higher up the rev range.
 
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They probably wanted a drop in replacement engine without
really updating anything else.

It was an end-of-life move.

Pity the 1750 wasn't around at launch, it could have made
the 159 a better seller in the EU market.
 

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I wonder if the ECU of the G has a different map or not. If its only hardware, I'd certainly be interested in modding a 159 1750 Tbi to have the same output as the GQV
 

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just read this quote on the AHM website!

" * - many standard cars, when first tested on our rolling road, produce more power than that quoted by the manufacturer. The Alfa Romeo Giulietta 1750 TBi Cloverleaf has a quoted standard BHP figure of 235. When tested by us we have seen figures of 260 BHP for unmodified cars. Following this we re-checked our rolling road and are confident that these results are accurate. "
 

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The camshafts are different I think, hence the G's power and torque being a little higher up the rev range.
The engines run at different boost levels. By the time the 159 engine has reached 5000rpm, the boost is depleted and cannot sustain sufficient air for more combustion and it therefore makes 200ps. The same turbo in the QV boosts 0.3 bar higher so it can supply boost to a higher rpm level and therefore the power output of 235bhp at 5500rpm.

Similarly, the QV boosts to 340Nm @ 1900rpm where the 159 engine does 320Nm between 1400 and 1750rpm. All that this means is that the extra 0.3 bar makes a difference in torque as well. I'm sure if you checked the QV engine, it would also have 320Nm at 1400rpm, but it would increase to 340 @ 1900 simply because of higher boost.

:thumbs::D
 

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The engines run at different boost levels. By the time the 159 engine has reached 5000rpm, the boost is depleted and cannot sustain sufficient air for more combustion and it therefore makes 200ps. The same turbo in the QV boosts 0.3 bar higher so it can supply boost to a higher rpm level and therefore the power output of 235bhp at 5500rpm.

Similarly, the QV boosts to 340Nm @ 1900rpm where the 159 engine does 320Nm between 1400 and 1750rpm. All that this means is that the extra 0.3 bar makes a difference in torque as well. I'm sure if you checked the QV engine, it would also have 320Nm at 1400rpm, but it would increase to 340 @ 1900 simply because of higher boost.

:thumbs::D
not sure, I think that the 159 can only achieve that torque figure at 1400rpm through having a higher compression ratio (and also a smaller turbo?) - otherwise they would just use the same internals:confused:
 

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"The engine of the Giulietta QV has been known for some time from the Alfa 159 TBi. In the 159 it delivers 200 horsepower. By applying a slightly larger KKK 03 turbo and a somewhat lower compression (9.2 instead of 9.5) the QV would have to deliver 235 hp. Honestly, we had our doubts about this with the knowledge we have gained with the 159 TBi. With a slightly lower compression ratio one can load some more boost pressure, which means that more power should come out under the line.

Unfortunately, we have not been able to measure the 235 promised horsepower.
We have tested a total of 3 cars which delivered on average 222 horsepower.


On average, we measured 344 Nm in the Dynamic mode which nicely corresponds to the promise of 340 Nm"


To compare my 159 TBi with Novitec Powerjet 3 lvl 7 and Novitec backboxes delivered 230 hp / 375 Nm


Squadra Tuning seems to know what they are talking about. They have lots of information and research done on most Alfa Romeo engines regarding tuning.
They are using a far more reliable Dyno, than most "chip tuning garages" do.

According to them max safe map for 159 Tbi is 232 hp / 382 Nm.



However, lots of chip tuners offers a 250 hp /400 Nm map for this engine.
Who knows if that is safe nor correct.


Squadra Tuning offers a 250 hp / 389 Nm map for the same engine in the Giulietta QV 235 hp version.
This engine however use a "modified" turbo and have different compression ratio (pistons)




Based on Squadra Tunings measurements, I made a rough torque comparing chart:
 

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