Is my car this fast???

[strosekmega]

I'm just asking becasue I had a great experience today...

Well, on my way down on 280 today (from San Jose to San Francsico) A black Audi A6 4.2 comes along to see what my car was about, he signs and we go for it... I got totally run over in the acceleration to about 130 Mph or so, but I was catching up and i passed him when my speedo showed 165 Mph or very close to 170. I was shocked to say the least, is this possible for my car? I'm asking because I might have to have my speedo re calibrated...

My car:

20k mile 2.7 liter engine, with some updates, no mods.

I have shaved the body from alot of weight though (No spare tire, no tools, fiberglass body, fenders flares, bumpers, wing and decklid)... and more is to happen in a few days. (deleting the AC unit approx 230-250 lbs more to save)

Is the 911s this fast? It really felt like 170! I have reached speeds up to 200 Mph in a Alpina B10 Biturbo before. Driven many fast cars, bikes etc. and had alot of "speed" experience. I guess I just never thought it would be that fast.... and I think I still had a few RPM's to give still.

so I wonder, what you guys have to say?

Picture on page 2!

[yelcab1]

Don't know about you, but my SC is 15% off in the speedo department. On the high side, that is. Shaving off weight helps acceleration, but technically does not affect top speed. According to Newton third law of motion, F=ma, top speed is when acceleration is equal to zero. At that point, Force is also equal to zero. That means engine horsepower is equal to drag. m (mass) is immaterial at top speed.

[Kroggers]

Hi Edward, I can not help with your q, but do you have some more pics on that nice car???

[Svensson911T]

It sound possible...

[on-ramp]

that pic rocks!

[IROC]

A basically stock 2.7? You need to get your speedometer checked. A basically stock 2.7 just doesn't have the horsepower to get you going much more than 140 or so (and that's on a good day). Top speed is all about the relationship between aerodynamic drag and hp. It takes alot of horsepower to get a car like yours above 150, let alone to 170 or so.

Mike

[Jim Smolka]

Also, depending on the gears in tranny, one can simpy hit the red line and not be able to go any faster. I don't think a stock 915 gear box can reach 170 MPH at ~7000 RPM's

[IROC]

Originally posted by Jim Smolka
Also, depending on the gears in tranny, one can simpy hit the red line and not be able to go any faster. I don't think a stock 915 gear box can reach 170 MPH at ~7000 RPM's

Good point. Assuming a 25" dia tire, a .83 5th and 8:31 R&P, it would take 7350rpm to hit 170.

Mike

[JackMan]

You went 160+ mph indicated on a public road?

Get your speedo and your head calibrated. If you run over a small cat at that speed you have some serious problems and I bet you don't have a fuel cell, cage, ambulance standing by, blah blah. Hey, I don't want to start a flame here, but .....

[David E. Clark]

Originally posted by JackMan
You went 160+ mph indicated on a public road?

... and posted a picture of your license plate on a public website!

[petevb]

>Get your speedo and your head calibrated. If you run over a small cat at that speed you have some serious problems and I bet you don't have a fuel cell, cage, ambulance standing by, blah blah. Hey, I don't want to start a flame here, but .....

...Don't want to start a flame war here, but on the right road, in the right conditions this is very safe. 280 is such a road- in the right places, 4 lanes wide and very straight. It is bumpier in some places than the autobahn, but in others it is actually better, with less traffic. 160 on the autobahn is totally normal if you have the right car. Sure, if you hit a cat you could have problems... how many cats have you hit on the highway? Under the wrong conditions or with the wrong car it's totally lethal, but I see the far side of 160 many times a week these days, and it doesn't even get the heart racing any more. And I'm not Joe racer around here- everyone else with a car capable is doing the same thing.

Besides, he was really doing about 130, and badly needs a speedo check.

[DougM]

Audi 4.2 has a speed limiter and I know it is definitely less than 160.

[slow&rusty]

Sorry I don't buy it....yor car I am sure is quick but you would have a rough time getting to 150mp/h

A 15% error (which is common) will bring your speed back down to a more believeable144 or so mp/h.

Still quick...and nice pic....I figure your license plate is to confuse the cops or someone trying to call it in....

Yasin

[JeremyD]

a wide body 2.7 - I would think frontal area will kill ya - I bet you weren't much past 130...

Find a handheld gps - that will tell you how far off your speedo is...

[SC-targa]

A wide body, mechanically injected, high compression 1974 3.0 RS will go 149 mph. Call it 150.

A stock, US 77 2.7 narrow body will run in the low 130's while a more powerful 1974 911S/Carrera will run in the low 140s. I'm going to bet you didn't even make 130 mph, but I'm sure it felt fast.

The Audi would have a 155 mph speed limiter.

You have a 230-250 pound AC unit? Wow, that thing must get cold.

Jerry

[masraum]

Your car will probably top out between 125 and 135 if you have a stock 2.7. Is the car in the pic you posted yours? It's a widebody, figure your top speed will be 5mph less than it would if you had a narrow body.

[Svensson911T]

How fast do the magazin say it can drive???

[ted]

165mph, maybe down a mine shaft with a tail wind.

[MichiganMat]

settle down boys, he's driving 280, 100mph is the speed limit out there.

[masraum]

maybe it wasn't 170mph, but was 170kph. That makes more sense.