"BMW 3 Series Coupe gets new engine"

BMW 3 Series Coupe gets new engine at

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Reply to
Mike
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Road test of it in this week's Autocar. Reckon it's as fast as an M3 in day to day conditions - you don't have to wring its neck to get some performance.

Reply to
Dave Plowman (News)

Also I have a question here: why is it that BMWs and Mercedes have this electronic speed limiter? Porsche AFAIK does not have one, is that correct - although there is a 'top track speed' in its specifications....Not sure if this is right... does it have to do with the tires, or is it an agreement between the BMW-MB to prevent people racing down the autobahn at insane speeds?

Reply to
RichAsianKid

Pretty much.

My understanding it, and I don't have an authoritative source for this, but I understand it's a gentlemens agreement to limit top speed for the reason stated above.

Reply to
Richard Sexton

I'm not sure I understand the premise of your question. The speedometer has no bearing on the Top Speed. The speedo simply reads what you are telling the car to be doing. The speed limiter kicks in with or without an electronic speedometer.

Why spin a speedo needle with a cable when you can pick up the data electronically from the main computer and display it? Speed is needed by the computer for many different functions, collecting speed data electronically makes it easier to distribute the data to the places where it is used. I don't know about Porsches, but I would be surprised if they do not use an electronic speedo.

And, if one bothers to actually work the numbers, one would find that top speed and red line arrive at pretty close to the same time. Limiting engine speed to below red line seems to make lots of sense to me, doesn't it make sense to you?

Reply to
Jeff Strickland

Well, there is an interest at the factory to not blow the motor into tiny bits. The motor is protected at red line, and top speed in 5th gear is pretty close to red line. I think it's about 250 rpm below red line.

Reply to
Jeff Strickland

The sensible mass market German manufacturers have sort of agreed not to compete on this, and if the cars are limited their government does not bring in an overall speed limit...

Reply to
R. Mark Clayton

However, the agreed Euro 'limit' is 155 mph.

Reply to
Dave Plowman (News)

Maybe I missed something, but where is "speedometer" mentioned in this thread?

For some (but not all) the current BMW cars limited to 155, this is close to redline in 5th, not the OD 6th.

Tom K.

Reply to
Tom K.

Sorry, I read Electronic Speed Limiter as electronic speedometer. My bad ...

Reply to
Jeff Strickland

What I don't understand is this from the article quoted:

"The acceleration from 0-60 mph takes 5.3 seconds with the 335i and 6.2 seconds with the 328i. The limited top speed of both the 328i and the

335i is 130 mph. With the optional Sport Package on the 335i, it is 150 mph. "

Very respectable # btw.

Sports package - used to be sports seats, more 8-way adjustable, M-tires, or M-suspension (depends on sports pkg or M-pkg), so how is this related to limited top speed? Maybe the tires or something.....

Jeff Strickland wrote:

Reply to
RichAsianKid

What I don't understand is this from the article quoted:

"The acceleration from 0-60 mph takes 5.3 seconds with the 335i and 6.2 seconds with the 328i. The limited top speed of both the 328i and the

335i is 130 mph. With the optional Sport Package on the 335i, it is 150 mph. "

Very respectable # btw.

Sports package - used to be sports seats, more 8-way adjustable, M-tires, or M-suspension (depends on sports pkg or M-pkg), so how is this related to limited top speed? Maybe the tires or something.....

Jeff Strickland wrote:

Reply to
RichAsianKid

The Sport Package includes a 150 mph limiter vs. the normal 130. Tires are summer performance instead of "all-seasons".

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Tom K.

Reply to
Tom K.

That's my point though - not sure how a sports package will get a 150 mph limiter vs a 130 mph one i.e. what's preventing a 328i or 335i without a sports package from achieving 150 mph? Other specs look comparable. Unless BMW has to deliberately detune the engine for business purposes. Perhaps like Mercedes SL/CL 55's not same power as SLK/CLK 55?

Reply to
RichAsianKid

Software. The ECU is programmed to begin limiting engine output (through the same process the rev limiter does) as the speed is reached. It's not absolutely precise (you may achieve 152 or so). The engine just goes soft, speed drops off a couple mph and you're done.

BMW religiously follows the German Gentleman's Agreement regarding top speed: 155. Particularly for the US market, they limit speed as well for legal reasons. They're concerned some idiot will fit speed rated tires inappropriate for the car's performance and then sue when the tires fail at speed, hence limits below 155 on some cars. Dinan, Conforti and others modify ECU software to improve performance. One of the mods is the removal of the top speed limiter.

R / John

Reply to
John Carrier

I gather it's a 'gentleman's agreement' among BMW, Merc and some (not all, obviously) others to limit the speed to 250 km/h (155 mph happens to be the miles equivalent). Nothing to do with tyres or motors. I think the main reason is to head off German government moves to introduce a national speed limit on motorways and to stop mostly untrained drivers driving so ridiculously fast on public roads.

I have been at (an indicated) 220 km/h in my 3.2 l car, but for no more than a few seconds because other traffic gets close mighty fast and I wasn't prepared to overtake at that speed. I wonder what might happen if I had to take unexpected action....

DAS

For direct contact replace nospam with schmetterling

Reply to
Dori A Schmetterling

Probably correct. Porsche seems to be the only non-participant. U.S. market cars all have V-rated or better tires as original equipment. But there are idiots who will fit poor quality aftermarket rubber to the cars and then can find idiots with law degrees to represent them after their folly results in some mishap. Then the idiot lawyers in robes allow the litigation to proceed to 12 more idiots who believe the money they award to the original idiot and his representative (30% plus costs for a fee) comes from a "rich corporation" whose wealth comes not from doing business with citizens like themselves, but from a source similar to that of the manna of Exodus.

The bard had it right.

I've seen a needle-width over 240 (approx 150mph) in my old toy. Several miles of desert road with zero traffic. I've gone faster on the ground, but only with the intention of taking off or immediately following touchdown. The F-4 had pretty high liftoff and touchdown speeds.

R / John

Reply to
John Carrier

Yes, but you may not have. You might want to look up the original quote.

Reply to
Richard Sexton

I don't understand the 'voluntary' speed restrictions makers apply in the US. Surely the standard tyres are rated way above these limits?

Reply to
Dave Plowman (News)

The speed limiter is built into the engine ECU. It can be programmed out by specialists.

Reply to
Dave Plowman (News)

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