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schliske

top speed

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How fast will these cars go? (on a closed course with a professional driver of course). I've got a 5-speed overdrive, Weber 45's, 292 cam, sport suspension and big brakes, 390 diff, v-rated track tires. I had it going 110 according to a speedo that wasn't matched to the diff and it felt it could go to the red line without trouble. I don't have any aerodynamic improvements yet. What will help the most? Any speed stories out there? Thanks-Michael

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depends on the track (length of straight, speed out of last corner before straight), car prep, driver, etc.

this is a touch over 120mph at T1 brake point. speed from GPS data acquisition, and you can see the buried speedo needle. first half of straight is slight uphill. no aero, 4.10, S14, race suspension, "professional driver", closed course.

lots more to be had on a longer straight...was barely in 5th gear and at bottom of power band.

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I've done an indicated 105, but I wouldn't trust the speedo. Stock other then a weber 32/36

Really no point in top speed for these cars; they are way more fun in the twisty bits. If you want to go fast buy a 1000cc super bike and knock yourself out.

I'm sure a slightly modified and well tuned 2002 can pull off 120mph with stock 4spd and diff. Gearing would be the limiting factor even on a nearly stock motor. I wouldn't try much faster than that unless if you do some aerodynamic work first (air dam to keep the front end planted). Getting to 150 would probably take an all out motor or mild turbo. Above that is really difficult, just ask anybody who's into land speed record stuff.

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Turn the question around and ask yourself, "How fast would I *want* to go in a 40-year old short-wheelbase aerodynamic brick?" One could drop in a F1 or NASCAR engine and go real fast, but even with a full cage, harnesses and containment seats (and helmet, of course), I am not sure I would want to do over 140-150 mph in a 2002. As an instructor I have been in a few cars doing 160+ mph, too fast for a 2002 IMHO.

Here's some info on things to consider:

The Physics of Racing

Part 6: Speed and Horsepower

http://phors.locost7.info/phors06.htm

HP must overcome air drag and rolling resistance

force of air resistance = 0.5 * Cd * A * rho * velocity squared

Power required to overcome air drag = F * velocity ~ Velocity cubed

So if you want to double speed, you will need 8 times more HP.

Thus, what will help is: less frontal area, lower drag coefficient, lower rolling resistance and more HP.

Speed-HP calculator

http://www.wallaceracing.com/Calculate%20HP%20For%20Speed.php

Example: Cd=.27, A=18 ft2, W=2500 lbs

41 HP to do 100 mph

283 HP to do 200 mph

Here's a tip--do NOT look down at your speedometer at the end a long straight, just before the brake zone, to see how fast you are going.....don't ask......

Fred '74tii and '69

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Fred is 120% correct. Really just about summed everything up.

If you really, REALLY want to go fast in a straight line, the first place to start after gearing will be aerodynamics. a complete belly pan and a proper splitter at the front can add a few mph to your top speed while also improving stability and downforce. Really though, for the amount of money you will spend on making you 2002 "fast" you could buy an old Hayabusa and do 200mph all day so long as you have the room.

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I've gotten my stock 76 (with a rebuilt motor, 32/36 weber and 4 speed-3.64 diff at the time) up to around 105mph with 3 other guys in the car, and that was scary; I wouldn't want to go much faster...

IMHO the cornering speed is where the fun is at!

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I've wraped the speedo around to touch the back side of the needle...on I-95 at 3am.. twas before we had GPS iPhone shenanigans though.

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Guest Anonymous

Creating the ability to feel like you are going fast is a thrill..fast is relative in these cars.......anyway a good free gps site is Ulysses speedometer......large numbers and pretty neat

ira

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depends on rear drive ratio, horse power, Euro vs USA version

16002002March1968prices.jpg

Euro versions:

1502 = 97 mph

1600 cab = 100 mph

1600 Ti = 108 mph

2002 Ti = 114 mph

2002 Tii = 118 mph

2002 Turbo = 131 mph

Ton-Up Club !

TonUp_Logo.gif

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How fast did BMW say the '74 Turbos would go with the identical "boxy" body of all 2002s? I run front and rear spoilers (similiar to Turbo's) and it helps make the car feel planted at speed.

A couple of times a month I drive the 65 miles up-and-back on the straight freeway between my home in Nogales, AZ and Tucson. Traffic is usually very light, but even driving between 90 and 95 indicated on the speedo (which is probably about 87-91 mph, in reality, since I have 185/60 x 14 tires) I still get passed by all kinds of cars.

I have an Eric Kerman built motor (w/ 12K miles) with 9.5:1 Mahle pistons, tii exhaust and dizzy, 38/38 Weber, and have Eibach springs, Bilstien HDs, 19mm anti-sway bars front and rear, Dunlop Direzza Sport Z1 tires (w/ 6K miles), fairly new rotors, calipers, and pads, and new steering linkage and front suspension within the past year, and the front end has been aligned by a shop in Tucson that specializes in BMWs. I feel comfortable and safe in my car at those speeds. Many times I've had the speedo up over 100 mph and the car feels very stable.

Bob Napier

post--1-13667669226739_thumb.jpg

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Thanks! Jeez, I wasn't trying to go for the land speed record, just curious. I agree the FEELING of speed is fun. I can go 100 and it feels like 130, and my friends' 330i goes 100 and it feels like 55. The curves are where it's at. I just thought that if I could just go 130 one time in my brick that would be that. I'm sure it's way more dangerous going 50mph through the I-70 to I-25 interchange in Denver.

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I'm sure it's way more dangerous going 50mph through the I-70 to I-25 interchange in Denver.

correct, because thats way to slow to stay alive in the mouse trap.

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