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NSXGB
03-02-2010, 02:21 PM
http://www.youtube.com/watch?v=W5EmrML3p1U

Senninha
17-02-2010, 11:34 PM
Long may the derestricted autobahns exist!!

I had a few runs into the high 160's nudging 170 when out on the 'Ringfest. Getting above these numbers takes a lot of concentration and tarmac! Cant wait to go back for more of the same :D

Thanx for sharing

NoelWatson
18-02-2010, 09:24 AM
Long may the derestricted autobahns exist!!

I had a few runs into the high 160's nudging 170 when out on the 'Ringfest. Getting above these numbers takes a lot of concentration and tarmac! Cant wait to go back for more of the same :D

Thanx for sharing

Paul and I have an indicated (real 164) ~175 when at VMax. Braking from those speeds down to ~60 is interesting

greenberet
18-02-2010, 05:01 PM
Nearly 300kph...? Only nearly? That hurts. 301 kph heading east into the rising sun and then 299 kph a few minutes later heading west on the same stretch of Autobahn. And if that anthracite Opel Zafira hadn't pulled into the fast lane heading west I would have stayed on the throttle longer and perhaps touched 300 kph in that direction as well. Perhaps.

In any case, I'm glad my engine didn't self-destruct because my crankshaft pulley/harmonic balancer failed while that video was being shot.

NSXGB
18-02-2010, 08:04 PM
Nearly 300kph...? Only nearly? That hurts. 301 kph heading east into the rising sun and then 299 kph a few minutes later heading west on the same stretch of Autobahn. And if that anthracite Opel Zafira hadn't pulled into the fast lane heading west I would have stayed on the throttle longer and perhaps touched 300 kph in that direction as well. Perhaps.

In any case, I'm glad my engine didn't self-destruct because my crankshaft pulley/harmonic balancer failed while that video was being shot.

My apologies, hard to see on the video!
Is your car standard or has it any mods?

WhyOne?
18-02-2010, 10:00 PM
Comment in YouTube:


....it's not stock. It has a foam air filter, polished intake manifold, ported heads, high lift camshafts, headers, and a sports muffler. But it is still a naturally aspirated 3.0 with a stock bottom end and a stock 5-speed transmission. And yes, that was 299 km/h in one direction and 301 in the other.

Senninha
18-02-2010, 10:29 PM
I'm pretty sure that GreenBeret has invested a lot of time on the aero package for his NSX. IIRC he has an almost completely covered underside to the NSX.

Dotn forget our very own Kowalski has camera and GPS records for his own 180+ mph runs in Europe. His is 3.0 with H/I/E and is decatted and pushes out over 290hp ... :)

regards, Paul

NSXGB
18-02-2010, 10:59 PM
Comment in YouTube:
Thanks Ian and Paul :)
I never read the captions on You Tube....maybe I should start!

greenberet
19-02-2010, 06:21 AM
I'm pretty sure that GreenBeret has invested a lot of time on the aero package for his NSX.

My wife would probably say that I spent a bit too much time on my NSX, period. Both WhyOne? and Senninha are right.

My NSX is a 1991 USDM Acura with the following horsepower modifications: Comptech airbox, Unifilter foam air filter, Extrudehoned intake manifold, Comptech ported and polished cylinder heads, Comptech high-lift camshafts, Cantrell ceramic coated headers, HKS muffler, and the stock engine management computer but with a chip custom-programmed by Autothority while the car was on a dyno. Amongst other things, the following are stock 1991: throttle body, VVIS plate, fuel injectors, intake and exhaust valves, pistons, cylinders, crankshaft, catalytic converters, and 5-speed transmission.

Regarding aerodynamics, I built complete front and rear undertrays for the car. It is also lowered a touch with Bilstein dampers set to their lower perch and for the top speed runs, I temporarily plugged the a/c condenser openings in the nose with pieces of Styrofoam and duct taped Procar front signal covers over the blinkers. From below, it looks like this:

http://www.nsxcb.co.uk/testvb/attachment.php?attachmentid=6605&stc=1&d=1266559949

From above, on the other hand, it looks stock except for the rear diffuser peeking out beneath the muffler:

http://www.nsxcb.co.uk/testvb/attachment.php?attachmentid=6606&stc=1&d=1266559949

I’m not sure how much the undertrays really impacted the top speed, though. In 1999, my car ran to an indicated 8000 rpm in fifth gear in one direction on the Autobahn and 8050 in the other on 245/40 17 rear tires without any undertrays.

http://www.nsxcb.co.uk/testvb/attachment.php?attachmentid=6607&stc=1&d=1266559949

One thing I found, though, is that you have to do a two-way run to determine the car’s top speed. Otherwise, wind or a slight hill could impact the measured speed. With a slight tailwind or on a slight slope, my car hits the rev limiter in top gear. However, since that’s just a one-way measurement, it doesn’t count.

http://www.nsxcb.co.uk/testvb/attachment.php?attachmentid=6608&stc=1&d=1266559949

NoelWatson
13-03-2010, 08:46 PM
I'm having doubts about the accuracy of GPS/speedos at higher speeds.

gumball
13-03-2010, 10:15 PM
Beautiful car there Greenberet, nice to see one perform so well without being reduced to bolting on blowers. These cars punch waay above their weight. :)

greenberet
13-03-2010, 11:59 PM
I'm having doubts about the accuracy of GPS/speedos at higher speeds.During another run, I had two GPS speedos in the car in order to double-check the results. A Palm TX fed with a GPS signal from an external Navilock BT-359 Sirf III receiver plus a completely separate Garmin Nüvi Sat Nav. The equipment was positioned at the base of the windshield for best reception and both clicked off the speed in lock step. In the picture you can see the same current, average, and maximum speeds on both devices.

http://www.nsxcb.co.uk/testvb/attachment.php?attachmentid=6667&stc=1&d=1268524537

Since GPS devices work by determining your position at regular intervals and then calculate how fast you must have been travelling to get from one position to the next in the given amount of time, they get more accurate the faster you drive. If your position is determined accurately to within 5 meters, when you’re driving slowly, the GPS device may think you’re driving a zig-zag course. If you’re driving zig-zag, you’re putting more distance behind you in a given amount of time than if you were driving in a straight line, so the GPS may overstate your speed. The faster you drive, the further the distance between the two measurement points, so the smaller the angle of the zig-zag and therefore the less your speed will be overstated.

What I’ve found makes a difference is if the GPS antenna is good and whether it’s positioned to get a clear signal. The GPS antenna in my Apple iPhone 3GS, for example, is miserable. Even when it’s positioned at the base of the windshield, it still has bad reception and loses satellites. I hope some future OS release will allow it to pair with an external GPS receiver. My Navilock is much bigger than the GPS receiver in my iPhone, but also much better.


Beautiful car there Greenberet, nice to see one perform so well without being reduced to bolting on blowers. These cars punch waay above their weight. Thanks and I fully agree. Still, it would be interesting to see what an NSX could do with a blower and a six speed transmission!

gumball
14-03-2010, 09:10 AM
A bit of a school kid question but... what does it do 0-60? :)

greenberet
14-03-2010, 09:30 AM
I don’t know. I’ve never done a timed acceleration run or even dropped the clutch. Since I have USDM 5-speed gearing, the 0-60 time probably wouldn’t be all too stellar, though.