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I got a friend who has an XR6 Turbo. It's an automatic (with kind of tiptronic mode) and has around 12,000km on it. So I met up with him tonight and not only did I take it for a good spin, we also did some comprehensive acceleration 'comparisions' ... but more on that later.

I was impressed with the car. It does not feel like a turbo at all, and no matter how hard I tried to trick it, it never showed any signs of turbo-lag. It just felt like a decent high-capacity engine and pulled well from idle. The steering really imressed me as it is very direct and the car is very responsive to it. Also it's not bad size/feel. It's certainly a lot better than what I have grown to expect rom cars like that. The car has a bit of roll ... maybe about as much as a CV8-R Monaro, so it's not too bad, but nothing as flat/stiff like the Zed, S2000 or even a top of the line HSV. The car does not feel like its 1685kg ... it feels good 150kg lighrter. Also it does not feel as big as it is ... it felt reasonably tossable and nimble around round-abouts, and was very willing to turn into corners. In corners it was very balanced where you felt like the car relies on it's front and back pretty much equally. On the limit it had understeer ... but it was predictable and also reasonably mild (that is I'm sureunless you're entring corners at way above what the car is capable of). Same with the rear - it was very well tied down and had very good power down. You had to really provoke it with the throttle to get some oversteer and then it was very controllable and predictable ... and this is around 40 - 60kph corners.

OK, onto the acceleration comparisons. Let me start by saying that the Zed (mine with the hi-tech exhaust) totally blew it away. It was never even close ... here are the details. We did about 20 different runs and some fair few times to get some pattern/consistancy. We both had only the driver on board. Also the XR6-T was manually shifted.

- Test #1: 0-120kph, agressive launch for the Zed and 'normal' launch for the XR6-T:
I launched with a clutch-drop (ie. ~2500rpm) and the XR6-T was just floored off idle. As soon as we went, I flew alway good 2 car-lengths before 40kph. It felt like the XR6-T missed the start, but the driver said that the car just took a 'moment' to respond. From then on I pulled away at a very noticable rate and by the time we shut down at 120kph, I was good 5 - 6 car-lengths ahead.

- Test #2: 0-130kph, agressive launch for both cars:
I launched with a clutch-drop (ie. ~2500rpm) again, and the XT6-T was power-braked to 2500 - 3000rpm and launched from there (with a bit of wheel-spin). This time things were very even off the line. Until my rear tyres hooked up we were side by side. If I got the launch a bit wrong, the XR6-T would get about 1/2 a car-length ahead of me. If he got it wrong, then I'd get about 1/2 a car-length ahead. Though, after 30kph (ie. once my tyres hooked up) I flew away in 1st gear, and by the end of 1st I'd always have good 1.5 - 2 car-lengths lead. Then in 2nd I'd pull away another 2 or so car-lengths and by the time we shut down at ~130kph, I was good 4 - 5 car-lengths ahead.

- Test #3: 10-130kph, rolling start in 1sr gear:
After that we decide to take the launch out of it, and did some rolling start tests. We did this a couple of times and the results were always the same. At the start we'd either stay even until around 30kph, or I'd be pulling away a little bit (ie. at most 1/2 a car-lengths lead by 30kph). After that I'd again fly away like a rocket and I'd have 1 - 2 car-lengths lead by the end of 1st. Then I'd pull out another 2 or so car-lengths in 2nd, and by ~130kph I'd be good 5 car-lengths ahead.

- Test #4: 10-130kph, rolling start in 2nd gear:
So we decided to see how it perfroms in higher gear. We started form 10kph again, but this time both in 2nd gear ie. the XR6-T stayed in 2nd for the whole run, and I only had to make the 2nd-to-3rd change. The XR6-T fared worse here than in the 1st gear rolling start and I would start pulling away straigh-away. I was pulling away at all times, and I'd even have a lead by around 30kph (ie. 1/2 way through 1st gear), I'd be good 1/2 - 3/4 car-length ahead. Then things went as in the other tests and I flew away to good 6 car-lengths lead by 130kph.

Afterwards we hopped in the XR6-T and tried to hand-time the 0-100kph runs. Of course, this is not very reliable or accurate, but still, this is what we got at best. We went by the revs to determine when the XR6-T reached 100kph in order to get some accuracy. We tried it with him driving and me timing and vice versa. btw, at this stage the XR6-T was pretty 'hot' and that does not favour the turbo at all (as the numbers show), but here are the best numbers we managed (with 2 on board):
- normal (ie. everyday) launch = 7.7sec
- Agressive, left-foot-braked launch = 7.2sec

So not too spectacular, but it agrees with the European magazines that tested the XR6-T recently. They managed 6.4sec when the car was 'cold', but could not do better than 7.3sec for 0-100kph when the car heated up. So obviously the XR6-T does not perform that great once it's heated up. Also I'm sure that the heat had some effect on the results I saw when lined up with the 350Z. Though, when we started the car could not have been that hot (ie. just normal driving) and I was still blowing it away ... maybe just not by as much. As it was I'd say that the '99 WRX (Auto) would beat it by a few car-lengths and the Astra Turbo would have been close. The HSV R8 (260kW) would annihilate it just as bad as the Zed.

In summary I'd say that:
- My exhaust accounts for good 2 car-lengths to 130kph.
- The XR6-T is pretty strong through the 1st gear (in particular bellow 35kph). Bellow 35kph it's very close to the 350Z, but above that the 350Z is noticably quicker.
- In 2nd gear the 350Z feels (and seems) a lot quicker.
- Over 100kph the XR6-T did not feel anywhere as strong as bellow 80kph.
- I'm sure a manual XR6-T would do better because it has more agressive gearing. Still, the magazines list the Auto only about 0.3 - 0.5sec slower to 100kph. And to 160kph they list them closer (ie. 0 - 0.3sec difference) ... so I would not expect any major improvement.

So the straight-line speed was not that impressive, but the car did feel great for a big family sedan. And the Auto bow was awesome ... not unlike the one in the Zed, but not as quick shifting and responsive.


Last edited by DavidM on 04-22-2004 at 01:07 AM
 

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Discussion Starter #2
here are the best numbers we managed (with 2 on board):
- normal (ie. everyday) launch = 7.7sec
- Agressive, left-foot-braked launch = 7.2sec

Hey, I just did some reaserch, and I had my gearing info wrong for the XR6-T when we did the 0-100kph tests. I thought the 2nd gear goes to 130kph, but it turns out that it goes to 140kph ... here's the XR6-T's gearing (at redline/6000rpm):
- 1st gear = 84kph
- 2nd gear = 140kph
- 3rd gear = 209kph
- 4th gear = 308kph

So with that in mind, we did not clock the XR6-T to 100kph, but 107kph instead. That very much invalidates the numbers that I listed in my 1st post (ie. the ones we measured).

Still, we can interpolate those numbers as it take about 1sec to go from 100 - 110kph. Therefore, it takes about 0.7sec to go from 100 - 107kph. Take 0.7sec from the times we clocked and you get a rough 0-100kph time:
- normal (ie. everyday) launch = 7.0sec
- Agressive, left-foot-braked launch = 6.5sec

If those numbers are accurate, then those are pretty good numbers in particluar if the car was running hot then. When I get the chance, we'll put a stop-watch to the XR6-T (again), but we'll time me accodring to the listed gearing.
 

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Good write up Zuffy - I've got a mate with an XR6 T and I'd agree with your findings that the Zed is quicker - but in my case, not by much
 

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I have not managed to run my friend again, but after spending more time in the car (and reading about them), I think that my runs were were not under perfect conditions for the XR6-T, as it was not performing at its best. Must have have suffered from overheating as I'm sure that an XR6-T runnning at it's optimal performance would make it a much closer comparision.
 

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Last night I drove another XR6 Turbo. This one is relatively new, and it's also an automatic with ~6,500km on it. To drive, it felt awesome. Car of that size has not right to feel that good. I'm not sure if the German cars of similar size feel this good. Excellent handling balance, great ride, and the steering feel is great. The car feels good 200kg lighter than it is and around roundabouts it's very chuckable (for a car of this size), quick to change direction, and also has very good powerdown.

The auto gearbox is awesome as I remember from when I drove the last one. Very responsive, and easy to drive even in manual mode. In manual mode the shifts are relatively responsive, and quick, and also the car holds the gear that you've selected and does not try to outsmart you. Loved it.

The interioir is 1st class in terms of layout and even build (bar Audi standard). The instrumets and controls are all very clear, visible and in the right place. Very quiet on the inside so the car is very solidly built.

The engine felt awesome as well ... you can't feel any negative effects of the turbo at all. Plenty of grunt at low revs, and smooth, linear power rise through the rev-range. Not a hint of turbo lag no matter what I tried. I have strapped a G'tech Pro SS on this XR6-T and returned the following (best) numbers ... the car felt quicker than the last one I drove, but should not too much of a problem for a reasonably driven Zed.

XR6 Turbo (auto), me driving:
- 0-10kph = 0.25 sec
- 0-20kph = 0.78 sec
- 0-30kph = 1.41 sec
- 0-40kph = 2.03 sec
- 0-50kph = 2.67 sec
- 0-60kph = 3.33 sec
- 0-70kph = 4.00 sec
- 0-80kph = 4.73 sec
- 0-90kph = 5.60 sec
- 0-100kph = 6.63 sec
- 0-110kph = 7.64 sec
- 0-120kph = 8.70 sec
- 0-130kph = 9.90 sec

Comparing this data to the data I got from my Zed, this is what I would expect to happen if the 2 lined up:

1. For the first 20m the cars would be very much side-by-side with the Zed battling wheel-spin and figting for traction off the line. My data actually has the XR6-T ahead by 10cm at the 20m mark ... which is by ~50kph.

2. After that, when the Zed would is able to put the full power down, it would start pulling away very quickly. By the time the Zed would reach 100kph it would be 11.2m ahead ... which is almost 2 car-lengths. This gap would be pulled in a matter of 3.5sec so the acceleration difference between the two cars would be very noticable.

3. Then the Zed would just keep pulling away in 3rd gear (while the XR6-T auto is still in the 2nd gear). By 130kph (ie. the 200m mark) the Zed would be 16.6m ahead ... so at this stage the Zed should be over 4 car-lengths ahead, and at this stage would be pulling away at the rate of ~7kph (ie. ~2m/sec).
 
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