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Nice :D

The gearing on that seems lower than on our B7, you have the 5 speed "dogleg" setup right.?

What are the max changing point on you beuty.

On ours it is according to a bit optimistic tacho

1 - 80 kph
2 - 140 kph
3 - 200 kph
4 - 260 kph
5 - 295-300 kph

Another thing, the turbo pressure did seem to loos a bit on high rpm. Is my obervation correct, if so why is that ?
 

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Discussion Starter #5
Eric,

Don't know what you mean by "dogleg" setup .

I did not push the car at his maximum rpm to avoid engine damage.
So I can't say for the max changing point. But with the "short" gearbox , it's rather low. I noticed that 120 km/h in 5th gear = 3000 rpm.

Regarding the loosing turbo pressure, it's my feet which slighlty releases the gaz pedal before changing the gear.

As you can see on the video, the max pressure is about 1,0 bar .
But I can go up to 1,3 bar when I turn the turbo pressure control valve .
I'm wondering if this is stock or a modification made by the previous owner, as I can read that the maximum pressure in normally 0,85 bar.

Your comment on this pressure question is well appreciated.

Sherlock .
 

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Sherlock said:
Eric,

Don't know what you mean by "dogleg" setup .

I mean 1st gear is back and to the left and the 5th as a 1 :1 ratio.


Sherlock said:
Eric,


I did not push the car at his maximum rpm to avoid engine damage.
So I can't say for the max changing point. But with the "short" gearbox , it's rather low. I noticed that 120 km/h in 5th gear = 3000 rpm.

.
OK that is much higher rpm than on our B7. We have app 145 kph at the same speed.

4000 rpm gives us cruising speed of 190 kph. :D


Sherlock said:
Eric,


Regarding the loosing turbo pressure, it's my feet which slighlty releases the gaz pedal before changing the gear.

Sherlock .
OK that explains it. :wroom:




Sherlock said:
Eric,
As you can see on the video, the max pressure is about 1,0 bar .
But I can go up to 1,3 bar when I turn the turbo pressure control valve .
I'm wondering if this is stock or a modification made by the previous owner, as I can read that the maximum pressure in normally 0,85 bar.

Your comment on this pressure question is well appreciated.

Sherlock .

That is definatly a modification. If I am not mistaken the max pressure should be in the area of 0.85 - 0.9bar as you your selves indicates.

I think the regulation area was between 0,5 and up to 0.9(0.85)
( 250 hp to 300 Hp)

1.3bar sounds very high and to me sound a bit dangerous unless you also make sure the engine get more fuel.
We have been running 1-1.1 bar for the last 10 years without any more problems than a blown head gasked, but I would never try to run at 1.3. It would be fun to try once the result should be terrifying but I do not belive the engine would last very long.
 

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Very nice :1:

What kind of result did you get on the dyno ?
 

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Discussion Starter #12
Erik said:
Very nice :1:

What kind of result did you get on the dyno ?
Erik,
here were the dyno results :

220 kw @ 4600 rpm (299 BHP :) )
474 Nm @ 4100 rpm.


Have to say that the curve was completely different than these of my B3S.
At 2500 rpm, where the B3S already produces 150 bhp, the B7 only hits 95.
At 4000, 225 bhp for the B3 and 278 for the B7.
At 6000, 320 for the b3 but only 261 for the B7, after the peak of 299 @ 4600.

For torque, it's also very unequal (torque in Nm below):

rpm/Min / B3 / B7
2500 / 355 / 255
4000 / 385 / 470
6000 / 375 / 305.

The two cars are totally different, and you can feel that at every moment on the road. For example, there is little differences in 4 and 5th gear acceleration in the B7, whereas in the B3 you 'd better down a gear to get the full power.
 

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Discussion Starter #13
Deckard said:
Is it getting the stripes?
Hi Deckard,

No I do'nt think I will put them again. I asked around me, but most of the people found them inappropriated on such a car. It's only appreciated by Alpina "connoisseurs", and there are so few of them... besides, over time they tend to deteriorate, + it make the washing and cleaning more complicated.
 

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Sherlock said:
Erik,
here were the dyno results :

220 kw @ 4600 rpm (299 BHP :) )
474 Nm @ 4100 rpm.


Have to say that the curve was completely different than these of my B3S.
At 2500 rpm, where the B3S already produces 150 bhp, the B7 only hits 95.
At 4000, 225 bhp for the B3 and 278 for the B7.
At 6000, 320 for the b3 but only 261 for the B7, after the peak of 299 @ 4600.

For torque, it's also very unequal (torque in Nm below):

rpm/Min / B3 / B7
2500 / 355 / 255
4000 / 385 / 470
6000 / 375 / 305.

The two cars are totally different, and you can feel that at every moment on the road. For example, there is little differences in 4 and 5th gear acceleration in the B7, whereas in the B3 you 'd better down a gear to get the full power.

Thanks.:)

But how come you have so strange results.

If memory serves me right the max power should be at around 6000 rpms.

The max Hp seems right, also the Nm ( I think ALPINA rated 460 Nm)

And then you only have 260 [email protected] rpms, strange.......

Can the dyno mess it up so much ?
 
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