Closed Course Top Speed - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Idaho Red Rocket 3 · 11-26-2011, 11:06 AM

What top speed have you been able to get your Boxster up to on a closed course ? Both of my Boxsters are factory stock. I find getting to top speed takes a little time and distance. My wife I were in the car together both times. The '98 had 130K miles on it at the time and the '00 S had 60K miles on it at the time. We have been able to do it twice so far. Once in the '98 Base at 153 mph and once in the '00 S at 166 mph. Both times the cars had a more to give but due to getting close to the end of the course, we had to get out of it. I think the Base could have hit 155+ and the S 170+ if we had more distance to work it. What can these cars actually do flat out on an open road like the Autobahn ? We need an American Autobahn.

BYprodriver · 11-26-2011, 12:30 PM

I Porsche quoted top speed for 2000 Boxster S 6-speed is 165-167mph?? & my speedo seems to read 2 mph fast with 265/35/18 tire, do you recall what rpm you hit in what gear?

Idaho Red Rocket 3 · 11-26-2011, 12:48 PM

On the '00 S run I was not monitoring the RPM as closely as the MPH. I believe it was above 6K but under 6.5K. Condition were 55 degrees, sunny/clear, light tail wind at about 3,000 feet elevation.

landrovered · 11-26-2011, 06:47 PM

That is really fast with no roof, that is the only thing that bothers me is the fact that German canvas will not stand up to pavement if one was to get light and flip. I feel a bit more secure with the Zeintop but that is only psychological. If I am going to be closer to 200 mph than 100 I want a metal roof.

Pat · 11-26-2011, 08:39 PM

I'd be very surprised if anyone has surpassed your 166. I think I hit about 155, but wasn't very comfortable doing so. I felt like the car started to get light around 140.

Idaho Red Rocket 3 · 11-26-2011, 08:44 PM

I have a matching color hard top. I put it it on for the runs. Realistically I don't think it would do much after a few seconds in a flip over at those speeds.

thstone · 11-26-2011, 10:55 PM

Wow! 153mph in a base! The best that I've done is 137mph on a racetrack.

In a rollover, all of the protection is provided by the roll bars (hoops), the top (hard or soft) is pretty much irrelevant to crash safety.

Idaho Red Rocket 3 · 11-27-2011, 12:45 PM

I have felt that light feeling a couple of times when driving alone. I usually do these runs with my wife in the car along with our protective gear (helmets, leather motorcycle coats and gloves) and I put about 50 lbs of ballast in the front trunk because the back truck has our luggage in it. The extra weight really smooths out the car. So with the top, wife, gear , luggage and ballast, I probably add 350 lbs to the car. I know it seems odd, but it works for us.

The Radium King · 11-27-2011, 12:59 PM

it's a known issue with the boxster that the speedo can read up to 10% higher than actual.

ProjectM96 · 11-28-2011, 08:10 AM

I recently took out 25 lbs of junk out of my rear trunk and about 30lbs of junk out of my front trunk. I went out on the highway last night and got up to 80mph. The car felt very unstable. I felt more tire vibration in the front than usual. First time feeling it. Tires are still in good condition. Alignment seems good to me.

I have been up to 129 and it also felt very unstable with the wind and the feel of the front of the car lifting off the ground. I am looking for a longer straightaway to try to reach my top speed. Maybe Pocono Raceway. Summit Point's straightaway is too short in my opinion.

stephen wilson · 11-28-2011, 08:43 AM

I'd leave the ballast at home. 50# will only increase the weight on the front end by 4% (more like 3% with 2 people), and will be a detriment to handling and braking.

As far as unstability @ 80, 55# is only 2% of the cars empty weight, not nearly enough to notice.

BYprodriver · 11-28-2011, 09:43 AM

Quote:

Originally Posted by stephen wilson

I'd leave the ballast at home. 50# will only increase the weight on the front end by 4% (more like 3% with 2 people), and will be a detriment to handling and braking.

As far as unstability @ 80, 55# is only 2% of the cars empty weight, not nearly enough to notice.

Always think twice before circumventing Porsche engineering that we have paid so dearly for.

Overdrive · 11-28-2011, 10:38 AM

Been up to an indicated 137 (according to the readout when I dared to glance at it), and wouldn't think of trying to turn the wheel at that speed...in any car, really. You definitely have to run through every gear, though, and I'd love to find an abandoned/closed runway of a couple of miles to try to see what it can really do...and maybe after putting on an AeroKit.

The Radium King · 11-28-2011, 12:28 PM

i've had my car to 150 (so said the speedo) on the highway (i know, i know ...) and the front end does get really light. i think it's (a) the third rad venting down, and (b) high presure in the wheel wells. unfortunately, no way to fix either of those easily.

Cartel · 11-28-2011, 12:50 PM

ProjectM96 · 11-28-2011, 12:54 PM

Risky taking a picture at that speed.

Cartel · 11-28-2011, 01:21 PM

At the time the photograph was taken, my vehicle was only mildly modified (Lacking KW V3's, AASCO LWFW, FVD Brombacher ECU Tune, RSS UDP, IPD Intake Plenum/75mm 997 TB, etc.). In my vehicle, I have reached speeds ranging from 147 MPH (as indicated via the odometer) with the top down to 172 MPH with the top up to 166 MPH with the top up and another passenger in the vehicle. 2 weeks ago I was surpassing 165 + MPH in a high speed run w/ a 996 TT and a V10 R8 on the interstates. Fun times.

Overdrive · 11-28-2011, 01:32 PM

Quote:

Originally Posted by The Radium King

i've had my car to 150 (so said the speedo) on the highway (i know, i know ...) and the front end does get really light. i think it's (a) the third rad venting down, and (b) high presure in the wheel wells. unfortunately, no way to fix either of those easily.

I dunno TRK, I figure an AeroKit/GT3 nose and spoiler would be an easy fix...just not cheap...so if by easy you also mean cheap, then yea, still not an easy fix.

landrovered · 11-29-2011, 05:55 AM

Just a word to the wise...it is becoming a frequent phenomenon to have people cited for speeding and or reckless driving because they confessed to breaking the law through internet braggadocio.

This thread is specifically geared towards top speed in a legal closed course setting and not on public roads. I would hope that persons participating in this thread would both understand the importance of and only condone the strict adherence to speed limits and safe driving while on public highways.

Don't be that guy ... like the two idiots in the silver corvettes that had a drag race, a wreck, a short Youtube career and then got arrested for endangering the public.

and now back to our regularly scheduled discussion...

The Radium King · 11-29-2011, 06:25 AM

aerokits are certainly an improvement and would increase downforce - it would stop a lot of air from getting under the car. i was thinking more to the fact that the centre rad on the box is angled so as to vent the air down; even an aerokit can't fix that. from what i could see it is difficult to angle it up as the bumper gets in the way. you could remove the bumper, drill the bumper or space the centre rad forward, but that's all work. the only easy soln i could was was that, if you deleted your front a/c condensers and plugged the vents on the bottom of your bumper cover, then the third rad would be forced to vent out the side with the two side rads.

it's also interesting to do some reading about wheel well pressure zones; it makes sense why porsche didn't vent the side rads onto the front brakes and sent the air out to the side instead. some vents at the top of the wheel wells would do good things for the boxster.