Acceleration times Boxster S

[mattatk]

G'day All,
Been doing the 0-100km/h run in my 2001 Boxster S (manual) recently & she struggles in at 6.9seconds. The book figures (depending on the book) state 5.9 s & two years ago I managed to pull off a 5.4s.
My question is drawing a long bow, what do you think could be causing this slight lack of acceleration?
Some history:
1. Changed the clutch last year (but didn't change the flywheel, although it had a few hot spots).
2. Changed the AOS after a bit of smoking, had to clean throttle body & wipe out oil from plenum chambers.
3. Tires are getting a little old (although there was virtually no wheel spin in test takeoff).
4. Regular oil changes with Mobil1 (mix of 0W-40 & 5W-50).
5. Use Shell V Power (98 octane).
My only guess is that the problem lies in the flywheel, as on the initial takeoff, the car appears to lurch forward, pause for a millisecond & then continue with the acceleration.
Any thoughts?
Thanks in advance,
matt

[ProjectM96]

Was traction control off?
Cars actually get better 1/4 mile times if the tires do screech at take off.

Where you mention the car lurches foward, I had the same problem with the old car I drove. I just slowed the speed at which I let go of the clutch. It seemed the faster I let go of clutch, the more the car lurches foward and pauses, slowing my time. So I started to let go of the clutch a little slower and it accelerated faster, no pause.

Also, is there something in your car adding weight? That might also affect it. Maybe when you ran 5.4, your trunk was empty, and now you might have extra stuff in the trunk.

[mattatk]

No extra weight, well fuel level might've been a bit different (within 10litres).
I do traction control (PSM) on & off runs, it only equates to a marginal difference.
I'll play around with the clutch release to see if it makes any difference.
Cheers

[racer]

How old are PLUGS and COIL PACKS and Air intake? it would seem maybe you are having a HP issue, unless this is a frequent habit of yours, in which clutch/flywheel issues could be something to consider.

Are your tires different? Ambient air conditions? Road surface the same? ALL of these will effect your times.

Historically, Porsches aren't built for "drag race" scenarios. The conservative times Porsche publishes imply they expect you to try to drive the car more than once, vs the usually very aggressive Magazine test results.

[mattatk]

Racer,
The plugs are 3 years old, I'm going to replace them when they arrive from Pelican Parts (I'm in Australia which leads to 3-4wks delivery delay unfortunately).
Coil packs are original as far as I can ascertain from the previous owner's history.
The air intake is original & looks immaculate.
The road conditions are almost identical (same country stretch) albeit about 10 deg C different air temp (not sure on air pressure & humidity??).

No I'm not a drag racer or hoon, I do a 6 monthly check of acceleration as a health check.
This is the first time the car hasn't come in under 6 seconds.

Thanks all, I'll post any findings incase anyone is interested.
Cheers,
Matt

[livi]

I am more impressed by you 5.4 sec run. How did you manage that? Generally it is often tricky to reach the claimed times, let alone even faster.

On a side note, I would love to live in Australia and I am current looking to buy a Boxster S. The combination must be brilliant.

[mattatk]

Livi,
I think it was more like good luck than any good skill! I'm an amateur & all my other runs were @ 5.9secs. I've been doing the run on a deserted country road @ night (maybe the thicker cold night air helps).

As for a Boxster in Australia....well they are a bit rarer here than what I saw in the States. Unfortunately most people that recognize it as a Porsche ask me one of two questions;
1. Couldn't you afford a 911?
2. Isn't it a hairdresser's car?
Sorry, no disrespect to hairdressers, but the macho culture is alive & well in Oz.
I don't worry too much, as I know what a pleasure they are to drive. I love the 986 S for it's raw driving experience (911 guys will now be laughing at me!!). It was embarrassing at shops the other day with my 4yr old. Walking past TV shop & one of the "Clueless" movies was playing on a display TV. Reese Witherspoon playing the blond bimbo pulls up at Harvard in a blue Boxster, my son gets all excited & shouts loudly for all to hear, "look daddy, she's driving a Porsche like yours!!"

Weather is perfect for a convertible, well maybe further north, as Melbourne gets PLENTY of rain. Come down to Oz you'll love it!

[ProjectM96]

Originally Posted by livi

I am more impressed by you 5.4 sec run. How did you manage that? Generally it is often tricky to reach the claimed times, let alone even faster.

On a side note, I would love to live in Australia and I am current looking to buy a Boxster S. The combination must be brilliant.

The Road & Track Magazine Test Driver almost always beats the manufacturers claim and the results of Car & Driver and other magazines.

[ProjectM96]

Originally Posted by mattatk

Livi,
I think it was more like good luck than any good skill! I'm an amateur & all my other runs were @ 5.9secs. I've been doing the run on a deserted country road @ night (maybe the thicker cold night air helps).

As for a Boxster in Australia....well they are a bit rarer here than what I saw in the States. Unfortunately most people that recognize it as a Porsche ask me one of two questions;
1. Couldn't you afford a 911?
2. Isn't it a hairdresser's car?
Sorry, no disrespect to hairdressers, but the macho culture is alive & well in Oz.
I don't worry too much, as I know what a pleasure they are to drive. I love the 986 S for it's raw driving experience (911 guys will now be laughing at me!!). It was embarrassing at shops the other day with my 4yr old. Walking past TV shop & one of the "Clueless" movies was playing on a display TV. Reese Witherspoon playing the blond bimbo pulls up at Harvard in a blue Boxster, my son gets all excited & shouts loudly for all to hear, "look daddy, she's driving a Porsche like yours!!"

Weather is perfect for a convertible, well maybe further north, as Melbourne gets PLENTY of rain. Come down to Oz you'll love it!

I had the option to buy a 1980's 911 or a 2000 Boxster or a 944 Turbo all around $10,000 and all around 200-230HP.

I chose the Boxster. It is simply a better car. A Boxster with a 911 engine would be faster than a 911 as proven with the Cayman S.

[livi]

Originally Posted by ProjectM96

The Road & Track Magazine Test Driver almost always beats the manufacturers claim and the results of Car & Driver and other magazines.

By violently raping the poor cars drive train, I suppose..

I have had my 85 Carrera for seven years and I will keep it for ever, if possible. I really enjoy to take it out on a fine day for a good hour or two in the countryside. But thats it. For more daily driving I could not stand the quirky, agriculture mechanics. Thats where I hope the Boxster will fit like a glove during the road salt free season.