Boxster, Hp And Acceleration

[HenryV]

I thought I'd share this with everyone.

I found an interesting formula at this website: http://www.cars-cars-cars.org/0-60-Times-Calculator.htm

If you convert everything into lb's, (1kg = 2.202 lbs) the formula is:

0-60 time = 0.504592 * weight of car in lbs * max bhp of car

This works very well for the boxster, various years, weight and hp ratings correlate quite well. Check http://www.autosite.com/new/ataglanceshell.asp for reported acceleration times (various magazine articles, under Research->Performance) or http://car-stats.com/stats/search/choosemodel.aspx (watch out for spyware pop-ups).

The curbweight for the '04 base and S in standard trim and manual transmission is 2811 and 2911 lbs respectively. That is a 2.7L with five speed and a 3.2L with six speed. The '04 carrera cabriolet weighs in at 3135 lbs by comparison (2959 lbs for the carerra coupe).

Here's an interesting table, I use mfg reported curbweights, not actual (typically higher)

Model      Engine        HP    Curbweight       0-60 est        0-60 act

986'97      2.5L        201      2750             6.90            6.7
986'00      2.7L        217      2811             6.54            6.5
986         2.7L        227      2811             6.25            6.2

986S'00     3.2L        250      2911             5.88            5.6
986S'04     3.2L        260      2911             5.65            5.3

987S-1      3.4L        280      2959             5.33
987S-2      3.4L        300      2959             4.98
987S-3      3.6L        320      2999             4.73
987S-4      3.6LX       345      2999             4.39

987 Coupe   3.4L        280      2811             5.07

996'00      3.4L        300      2911             4.90            4.9-5.2
996         3.6L        320      2959             4.67            4.8-5.0
996         3.6LX       345      2959             4.33 
997?        3.8L        360      2999             4.21        

996'00 Cb   3.4L        300      3095             5.21            5.2-5.5
996 Cab     3.6L        320      3135             4.95
996 Cab     3.6LX       345      3135             4.59
997? Cab    3.8L        360      3175             4.45  

If the 2005 boxster were to have a 300hp engine or larger, it would out-accelerate the '00 996! Hence the rumored 280hp 3.4L (eventhough this engine makes 300hp in the 996).

(Older models don't matter: e.g. http://home.gagme.com/greg/911/comparison.html )

I have been told that the boxster S frame, transmission and brakes can handle up to 350hp without modification. Ah well, maybe in 2006, when the boxster coupe (is lighter?) comes out . . .

And - don't ding me on the actual curb weights (= actual acceleration) - There are other variations (weight of driver, tank empty/full, etc.). But I do think the table brings out the marketing point quite well.

Also, compare these spec's:

               986          996
Wheelbase     95.1         92.6
Track         57.3/59.6    57.7/59.1   
Length        170.1        174.5
Width         70.1         69.7
Height        50.8         51.4
Wt. Dist      46/54        36/64

Porsche claims that the extra weight on the rear's (996) helps acceleration, but we all know that it makes aggressive driving more tricky. Imaging both cars with similar horsepower.

FWIW . . .

I will, seriously, consider the (300hp) 3.4L conversion versus buying an '05 or '06 boxster :jump:

[HenryV]

In case you haven't seen Trent's website:

Check Trent's website for the 3.4L conversion - http://www.trentcarter.com/3.4Boxster.asp

His cost: $10k, versus the typical $25k

[mrmickeymouse]

He also blew his motor, buy upping his S/C boost a little to much. Gotta [sic] know when to say enough...

:eek:

[Tool Pants]

From what little I know forced induction on a motor with an 11 to 1 compression ratio is like playing with a hand grenade, but it sure was fun while it lasted.

Rami's twin turbo 3.2 has 365 hp but I do not know if that figure has been bumped up for drive train loss. http://www.ramis-porsche.com/index.htm

The twin turbo 3.2 that was on the cover of Excellence last year is for sale. On the dyno the highest hp at the wheels was 318. http://cgi.ebay.com/ebaymotors/ws/eBayISAP...item=2475466489

When the 996 went from 3.4 to 3.6 in 2002 I was hoping that the 2003 face lift Boxster S would get the 3.4.

The Boxster is a heavy car. Wish there was some way to remove 1,000 pounds and still have a street car

[Viktor]

The formula should read:

0-60 time = 0.504592 * weight of car in lbs / max bhp of car :oops:

[adsach]

re:>>From what little I know forced induction on a motor with an 11 to 1 compression ratio is like playing with a hand grenade, but it sure was fun while it lasted.<<

My best friend had an engine from a 62 olds Jetfire. The Jetfire's 10.25:1 compression gave 215 HP @ 4800 and 300 lb/ft @ 3200. This was a 215 cu alumimum V8 using 1962 technology! He ran it successfully with 15-16 lbs boost.

The secret of the Jetfire engine was to build it strong - torquing the head required a trip to the manual, since it is not an intuitive pattern for a cylinder bank with 18 main bolts.

The Boxster engine isn't built with 6-bolt mains - so one has to be a quite a bit gentler.

[rxbox]

lets face it guys....porsche doesnt want to draw away from its 996 buying crowd

seems like they take baby steps with the upgrades

have you guys ever read the reviews in road and track?

986 s lateral acceleration (200ft diameter circle) is .95g's on the skid pad:...

-only the corvette c5-r, viper srt-10, the enzo, ford gt 40, saleen s7, ruf rturbo, and our own gt-1 and gt-2 beat us

and slalom (8 cones spaced at 100ft intervals) is 71.6mph:...

-only cars that beat the 986 s were the enzo and viper srt-10 comp coupe...we even beat our own family to king of the hill....

so if you want to feel power...take on an autocross...check out local pca or other driving clubs and unleash the adrenaline!

i tried last year and now i'm an autox junkie (all you need to start is a helmet)

look here:

http://www.scca.org/Inside/Index.asp?IdS=0...egionalSites&~=

Edited April 29, 2004 by rxbox

[adsach]

That 71.6mph is an S with M030 - If you don't have the 030 Factory tuned suspension, expect your speeds to be down a little bit (towards the Carrera numbers)

[rxbox]

how to check if my 2002 has mo30 tuned vs other?

ive read some of the posts on the carrera side and just starting to understand the x74 vs m030 controversy..

looked up r&t but they didnt state if the test car was special order or not...

i'm curious as to what i have in mine....

i cant outdrive my car yet but if changing struts and shocks will make it that much easier for a novice to handle a curve....i'll do it.

the feel of the road with just the h&rs was tremendous compared to stock.....but with my gt2 nose i am currently always on the look out for driveway angles

any input greatly appreciated

ric

[adsach]

re >how to check if my 2002 has mo30 ?<

read the sticker inside the hood. probably less than 20% of Boxsters were delivered with M030. Some folks went aftermarket on 030 because the rest of the world(ROW) 030 is about 1/2 inch lower on the springs. Other than that, you can try reading the paint colors on the springs.

ooops - Since your signature file shows you have H&R springs and front and rear stabilizer bars, whatever setup you have is not factory (M030 or otherwise.) The only way to tell how good you have is to test it out and see how she drives! Until the new PSS9 suspension, H&Rs were the most talked about aftermarket choice.

enjoy!

[rxbox]

still have the springs in the garage...will take a look

made a nasty mistake at an autocross yesterday

had my front tire psi at 40 and rears at 40....understeer'd like crazy

loosened up the front strut bar

took it down to 38 then 36 to front with no change, went to 42 then 44 on the rears...which did help a little....finally 46

when i deflated the tires on the ride home..checked the gas cover and was surprised to see fronts supposed to be 29!

no wonder my sidewall chalk marks never scuffed off

well...i love this car and can wait to get that "riding on rails" feel

[adsach]

40PSI is a lot for a Boxster with it's relatively fat tires. I consider this the maximum HOT temperature.

40/40 usually produces lots of Oversteer(ie rear end comes around).

On street tires:

32/26 COLD produces mild understeer.

34/36 COLD produces mild oversteer.

29/36 FACTORY recommended produces the kind of massive understeer I used to experience driving my high school sweetheart's '75 Toyota Celica. IMO opinion a Boxster should not corner like a Celica.