Broke 300 km/h!

[greenberet]

This morning just after dawn I managed to get my NSX up to 304 km/h (189 mph), measured by two separate GPS devices. The autobahn I was on runs parallel to the Isar river, so it's almost completely flat. The wind socks on the side of the road were just dangling there, not showing any wind. The last few km/h came really slowly but my Garmin Nüvi and the Cetus GPS software running on my Palm Pilot clicked off the increments pretty much in lock step.

I'm not sure why I managed to get up to 304 km/h today and only 299 km/h the last time I measured the top speed. Maybe it was the cooler temperatures, maybe it was the almost complete lack of traffic which allowed the throttle to be floored for a really long time, maybe there was a tailwind in certain places even though the wind socks didn't show any.

In any case, I was happy to see a maximum speed above 300 km/h. Yeah, baby!

 

[heySkippy]

Awesome! Color me green with envy.

 

[BioBanker]

That is just awesome. What mods do you have?

And to think that it is a remarkable accomplishment for any car these days to top 200mph, which isnt that much faster then what you went.

Great show!

EDIT: Mods below:
NSX Details:
1991 Berlina Black / Ivory; Comptech airbox, air filter, cylinder head work, camshafts, high flow oil pump, clutch, flywheel, short shifter, brake lines, rotors; Extrudehoned intake manifold; Cantrell headers with ceramic coating; HKS muffler; Autothority custom engine management chip; Bilstein shock absorbers with custom valving and snap ring grooves; NSX-R front sway bar and chassis bars; 2002+ OEM wheels; Procar front blinker covers; Homemade complete front undertray; Dali window regulator fix-it thingies; SoS billet door handles; VDO oil temp gauge; SmarTenna; Alpine MP3 changer

 

[AR]

Well done!!!

 

[TyraNSX]

I'm curious. Did you have to shut off TCS to get the last few km/h? It has been reported on here that the TCS kicks in at extreme top end & the light comes on. The only way around it is to shut it off. There's at least 1 thread on here that mentions this, I think with pictures. Looks like your avatar shows it happening.

 

[greenberet]

Yes, I did have to shut off the TCS. I forgot to do so at first and at about 280 km/h it felt like a speed limiter kicked in. I wanted to kick myself in the butt for forgetting to turn the TCS off because I had ruined my chances of getting to top speed on the straight I was on. I slowed down a little, turned off the TCS, and then the car was able to accelerate further. Instead of the speed limiter kicking in, the TCS failure light came on. I assume that happens because the TCS thinks it is unfeasible for the rear wheels to be rotating so quickly.

 

[pegi]

Wow, great speed... :smile:

 

[Greg Z]

Incredible!, and that thing is NA?

 

[PAUL M]

Wow Thats awesome. What tires are you running? Make sure they are speed rated for it.

 

[jond]

Wow Thats awesome. What tires are you running? Make sure they are speed rated for it.

That's what I was thinking. Shit, I would probably get my tires x-rayed on top of that. A blowout at 190mph is probably not a good thing.

Did you take any video by chance?

 

[Jonmarsh]

Quite impressive- - are your mods for this run as posted in your user profile?

You've gone along the same lines I've been thinking of and working towards, with NSX-R chasis updates, aero bits, and comprehensive I/H/E + chip.

Two thumbs up! Any pics of your X?

I've been thinking about a Garmin 670, didn't know you could do things like that with them. :biggrin:

~Jon

 

[Swift]

next time you are up for that speed see if you can get a flyby of it...i want to hear what an nsx sounds at warp speed!!

good job!

 

[nsxvtecvtec]

INSANE!!!!!!!!!!!!!!!!!!:biggrin: maximum speed i tried is 125 mile/hr .lol. over 300 KM must be insane.

 

[MvM]

Wow, that's incredible. Congrats at reaching that very rare speed.

And to think that you don't even have a supercharger to achieve that :smile:
Am wondering, have you dynoed your car with the mods you have?
Would very much like to know how much power your car is making. Especially at RPM's above 7300, because.
Also, would like to see you front bumper underside. What did you make your undercover from? How does the car feel at 300 km/h. Any different than from 270 kp/h?

 

[enkrypt3d]

Damn dude thats impressive... my all time personal top speed is 155MPH and I ran out of road.

Has any NSX ever topped 200mph? Is it possible with the proper mods to the engine and transmission?

 

[RON98]

sick

fastest i went was 165. 180+ is a real acheavement.

CONGRAts!

:biggrin:

 

[BD]

What was the RPM when you hit that speed?

 

[RON98]

VIDEO PLEASE!

:biggrin: :biggrin: :biggrin: :biggrin: :biggrin: :biggrin:

 

[greenberet]

Thanks for the complements! To answer the questions:

Mods: Yes, the mods are as BioBanker listed in post #3 above. My engine is a naturally aspirated 3.0 with a stock bottom end and a stock 5-speed transmission. In addition to the mods listed, I closed off the a/c openings in nose because I hope that reduces the wind resistance.

Tires: I'm running OEM 2002 sizes, Y speed rated to 300 km/h. Since the NSX is light and doesn't get close to the tires' load rating, it should be safe to go a bit over the speed rating. I hope.

Video: Unfortunately, I don't have one. I have neither a video camera nor a video camera mount and I didn't want put my little digital picture camera into video mode and hold it in one hand at top speed. And my wife didn't want to come along.

Pics of NSX: Attached is a picture I like that I took back in 1999 in my garage. The other cars belong to my neighbor. Those cars are only part of his collection.:smile:

Dyno: A dyno graph can be found here and I can't see how to re-post it in this thread. "Prad" is the measured power at the wheels and 195.5 kW equals about 265 rwhp, as measured on a Bosch FLA 203 chassis dyno. The "Pmax" figure is the calculated maximum power at the crankshaft which includes "Pverl", the assumed drivetrain loss.

Undercover: Pictures and a description can be found here.

Feel at 300 km/h: To be honest, it didn't feel that much different at 300 than it does at 270. The biggest difference is seeing a 3 as the first digit in the current speed display instead of a 2. But it's nice to see that! The car still felt completely stable at 300 when it was floored but it felt slightly less stable when I got on the brakes to slow before reaching a turn. Maybe the aerodynamics changed as the nose went down a bit. Maybe I was just chicken and imagined it.

RPM: the needle was covering the lowest of the three horizontal sections of the 8. I don't have any independent measurement of what rpm the engine was actually at. Also, the speedometer looked like it was pretty much at the last of the little dashes after 180 mph, but I could be wrong because those are hard to see.

I also think it would be interesting whether an NSX with a 3.5 or 3.8 liter engine or with forced induction could pull to 8000 rpm in top gear if it had a 6-speed transmission. goldNSX, are you listening? Get rid of those short gears!

 

[goldNSX]

goldNSX, are you listening?

Yes, I'm here and shocked by your 300+ result that I'm not able to comment it. Simply sick. j/k

Congrats on your numbers! You must have a very, very strong engine, even with the mods.

Get rid of those short gears!

The FD 4.23 and the now smaller tires limit my top speed to about 270/280. As you also live in the alps you know where I like my setup. :wink:

 

[Big_D]

Incredible achievement. I can't imagine going that fast. I start getting nervous at 140 mph.:redface:

I hope that road is fenced off so no little critters can jump out in front of you.

 

[Arshad]

DAMN!!!!

Particularly impressive since it's NA! Anyone with FI go beyond this speed?

 

[TURBO2GO]

wow... NA angine and 5 speed. Does someone know for fact what the 6 speed will redline at? I think someone said earlier it was 202?I would thibk with forced induction and a 6 speed high 190's is easily acheived..

 

[NSXGMS]

wow... NA angine and 5 speed. Does someone know for fact what the 6 speed will redline at? I think someone said earlier it was 202?I would thibk with forced induction and a 6 speed high 190's is easily acheived..

Yes, redline in 6th will result in 202 mph. I believe the hp needed to get there would be north of 450 whp. This has been discussed before but I can't remember where. Most certainly a high-boost application would get you very close to 200.

 

[NeoNSX]

That is extremely impressive!
Did it take long to hit the last 20mph?