Friday, December 19, 2008

GTR high speed acceleration

Essentially the GTR is a fast car not only because it has a wide spread of torque, dual clutch transmission, great aero, AWD etc, the gear ratios are really close and biased for low-speed i.e. under 100 mph, which is where almost all driving is done. Makes perfect, logical sense since practically everyone will be driving under 100 mph anyway.

Been looking at some accel figures and the car really starts off strong but beyond 100 mph it starts to slow down quite a bit as compared to its contemporaries.

Acceleration of various cars going 60-130 mph

Second to last graph, the Stage 1 GTR takes 7.8-4.5 = 3.3 seconds to get from 100 to 120 mph. By way of comparison a Z06 tested by C&D takes 11.0-8.3 = 2.7 seconds to get there. A ZR1 takes 2.4(!) secs. From 120 to 130 mph, GTR takes 10-7.8 = 2.2 secs, Z06 takes 1.7 secs and ZR1 takes 1.9 secs. Slightly longer, most likely due to gearshift.

So taken in totality 100 to 130 mph, GTR takes 5.5 secs, Z06 requires 4.4 secs and ZR1 needs 4.3 secs. In a short sprint, choose the GTR. In an all-out pedal to the metal autobahn stormer, stick with American muscle.

Thursday, December 11, 2008

Leno reviews his Corvette ZR1

This is the car I would like to own if I'm still living in the US. I really like the C6 shape.

Thursday, December 04, 2008

Disgustingly quick and fast Evos

APC's Evo 2 lays down 7.97 @ 176.96 mph in Australia. Full frame and AFAIK no nitrous. Respect.

Here's their website. And old time slips in the 8.0x range.

Based on my regression analysis of 1/4 ET from 1000' times from 3 years ago, here is the outcome.

Run 1Run 2Run 3
Actual 1000 ft (s)6.7996.8256.862
Predicted ET (s)8.0780568.10788.150128
Actual ET (s)8.0778.1088.162
Residual error (s)0.001056-0.0002-0.011872


And here's the prediction for 1/8 mile vs 1/4 mile trap speeds.

Run 1Run 2Run 3
1/8 mile trap speed (mph)137.95137.45134.73
Predicted 1/4 mi trap speed (mph)176.7176782176.0575569172.4664974
Actual 1/4 trap speed (mph)176.26175.51173.14
Residual error (mph)0.4576781790.547556946-0.673502563






Here's another Evo 2, piloted by Mike Reichen going 221 mph in the standing mile. In 2005 Road and Track ran a standing mile test and their fastest car, a Hennessy Viper, did 210.2 mph.



Wednesday, December 03, 2008

Did Nissan supply GTR ringers to American motoring press?

One thing that always bugged me is the inconsistency between what the press publishes and what the public sees and experiences. In my own testing on our local dyno the GTR lays down about 390 whp, time and time again. Yet the American press keeps insisting that it was higher than that. I was skeptical and preferred to stick with my own experiences until I came across this article on Car and Driver.

According to the article and their supplied test sheet, their car went 11.5 @ 124 mph. This is not unexpected. The fine print is that their test facility's elevation was 4200ft!

Now the question is, how was their test car obtained? Was it through Nissan USA or purchased off a dealer lot?

Update: Thanks to MT who supplied a link to Car and Driver's position.

What I'm not happy with is that they didn't have the journalistic integrity and balls to grill Nissan on why they were supplied with what is undoubtedly a ringer. Basically the rest of the article just white-washes away this fact, spin control.





web statistic