As far as I am aware the only limiters fitted are those that restrict higher end cars at 155 mph.

There is a new kind of limiter on the E60 M5 that has a "second limit" of about 167mph though.

I assume the revlimiter is set at 6500 in which case when your doing 3.25 in 5th multiply it by 2 then that's your theoretical top speed.. Mind you since the power band drops off dramatically I'd assume you wouldn't have enough power to go much faster then the 149 anyway.. however down very long straight hill wind assisted... you never know...

Starfury, a cars top speed is determined by it's gearing and aerodynamics. A car will not go much past it's peak power, depending on how quickly power drops off after this. Top speed will probably be how fast the car is going in top gear at around peak power RPM. Even if you doubled the power output, if it's developed at the same RPM you will not increase the top speed. However once you reach a certain speed the wind resistance also will stop the car getting any faster. Wind resistance is very hard to overcome and normally determines how fast a car will ever go regardless of power or gearing. For example a mark 1 Escort hits a wall of wind resitance at 140mph. Even with a 400bhp cossie motor it will not go any faster.

The Honda Civic has a similar top speed, because of it's gearing and power curve. Also it may only have a 2.0 engine, but it does have a higher power output than the 2.8. The weight difference will affect acceleration but have very little effect on top speed. 

Finally speedos are nor very accuruate. This inaccuracy increases the faster you go. As a rule of thumb it reads 10% positive, so if it reads 150mph, you may only be doing 135mph.

Interesting post, I was going to ask a similar question about the 330, but from another angle...

BMW claim 231BHP for the 330 with a max speed of  155

Do we suppose this top speed is WITHOUT limitation or do you think the car would go even faster?

I cant see it myself and am surprised that it reaches 155MPH anyway..

Has there been any independant tests of this car that prove that it does indeed hit 155?...(not a speedo reading from someones local bypass)

the 2.8 is an old engine now and 200BHP only gets you so far ,unless the car is shaped like a cigar tube, as someone mentioned above, it takes a disproportional amount of power to gain an extra 5-10 genuine MPH

As has been mentioned, it comes down to power, resistance, gearing and weight. The required power squares with the increase of resistance (if i remember right), so doubling the speed requires four times the grunt.

The gearing comes into it when you hit the redline/limiter or whatever and where abouts in the powerband you are.

My M3 is limited to 155, but it would probably go slightly higher (maybe close to 160) before you hit the redline. That's (on paper) got about 290bhp, delivered at 7k rpm.

My wife's Leon Cupra isn't limited - book speed 142ish - and when you get close you just hit a wall where the resistance from air/road cannot be outweighed by the power available. And it's still a way off the redline. That one's about 180bhp at 6.5k rpm(ish) and a LOT lighter than the M3.

So two cars - 110bhp between them, and probably 18mph difference in the top speed! But it's an unfair comparison as the M3 weighs about 300kg more, is a different shape and geared differently. 

brybusa - I'd be surprised if the 330 could get that high, but as has been correctly stated any model that can exceed 155 is limited to that anyway. An agreement between BMW and Mercedes IIRC.

A delimited E46 M3 goes to 168mph.

Well worth it...on a long road.

Peter Fenwick wrote:   Finally speedos are nor very accuruate. This inaccuracy increases the faster you go. As a rule of thumb it reads 10% positive, so if it reads 150mph, you may only be doing 135mph.

as a genral rule of thumb ..id agree with you on this one ..but i was amazed to see 190 mph on the clock of a motorbike of mine while doing some track days in the past ...and i thought yeah what a load of old tosh .the bikes only tested at 182mph..so i thought just another over happy speedo...but the speed gun on the start /finish straight had me clocked going through at 188mph to 189.4 mph ...so upon untill that day i would agree with you ..but .on that particlure track day ..id have to disagree with you pete .lol

pma1ums wrote: Peter Fenwick wrote:   Finally speedos are nor very accuruate. This inaccuracy increases the faster you go. As a rule of thumb it reads 10% positive, so if it reads 150mph, you may only be doing 135mph. as a genral rule of thumb ..id agree with you on this one ..but i was amazed to see 190 mph on the clock of a motorbike of mine while doing some track days in the past ...and i thought yeah what a load of old tosh .the bikes only tested at 182mph..so i thought just another over happy speedo...but the speed gun on the start /finish straight had me clocked going through at 188mph to 189.4 mph ...so upon untill that day i would agree with you ..but .on that particlure track day ..id have to disagree with you pete .lol

Nice one, you are right some speedos are more accurate than others.

In my experience though a lot of cars are quite inaccuruate. On my site we have digital meters at the side of the road that tell you how fast you are going and if theu are correct my car is only doing 28mph when the speedo reads 30.  

Bike speedos generally are far more accurate than car ones, especially the newer digital ones...if the bike in case was good for a true 182MPH, 190MPH on the clock is a good level of accuracy id say.

the most recents tests of the new Ducatis have showed a near 100% accuracy

Anyway, e46 330 coupes,whaddya reckon they would do with no limiter?..Im guessing 155.5MPH...!

I've managed 140mph from my 323 Saloon, with a little left, that's from a 170bhp engine, I would imagine the 328 would easily reach 150 and behond with 193bhp on tap???

NewBMWOwner wrote: I've managed 140mph from my 323 Saloon, with a little left, that's from a 170bhp engine, I would imagine the 328 would easily reach 150 and behond with 193bhp on tap???

It takes a lot of extra power to go another 10mph. The top speed of the 328 is determined by the gearing and the RPM that the power peaks at. Since power dies off quite quickly once you get past 5000rpm it ain going to go much past 5k in top. If that equates to 145mph or so then that is as far as it's going to go. As I have said before it doesn't matter if you have 193bhp or 1093bhp, if it peaks at 5K rpm then top speed will be determined by how fast that equates to in top gear.

It does take a lot of extra power to get an extra 10MPH, especially when you get into the "bigger" numbers...

Which is why I find it funny some peeps claim after a chip they can get an extra 20MPH out of their 318....

Starfury wrote: This has become a very hot topic :) In my 328i I hit 60 in second gear at about 6000rpm.... now the reviews I have read they said they power past 60 in 2nd gear, yet I have to change gear to 3rd the moment i hit 60. Whats wrong?

Is this just before the pistons power past the cylinder head and thru the bonnet on their way into orbit?  

E36 M3 (5-gear) will just top 60 in second before you hit 7k rpm, so i just change gear.

I've just been out in mine and it will do about 65mph in 2nd although this is at about 6500rpm just before the limiter cuts in. TBH I would normally change up at about 5500.

See, Star fury, itll do it, you just need Peters mechanical lack of sympathy...!

Off topic I know, but I shall be out on the bike at the weekend for the first time since Oct 2004, any bets on what I get out of that in second?

6500 rpm?? Ouch. My cars rarely get past 4000 in any gear, no point revving that high in search of a couple of bhp so I prefer just to cruise up to speed.

As for the bike, probably about 100 in second!

 Doive, quite a few bikes do over 100 in first now mate...

There's a truer (if that's a word!) speedo built into the computer (for those that have the full computer fitted!) 

Once you unlock the computer (Something to do with no.17 and adding the month and day of the date together I think - will check this if someone needs to know) It's test no.8.

Quite suprising how much my car over-reads - at and indicated 70, I'm actually doing 64!

brybusa wrote: See, Star fury, itll do it, you just need Peters mechanical lack of sympathy...!

Lack of mechanical sympathy! WTF.

The 328 engine does not redline till 6200rpm. Occaisionally taking a cars engine to the redline and slightly beyond does not display a lack of mechanical sympathy. The engines are designed to be able to take it and infact multivalve engines are designed to be revved. After all whats the point of having variable timing that doesn't come in till 4K then changing up at 5k.

Starfury wrote: Supercharger, Twin turbocharger and a 100 shot of Nitros it is then. This should be fun :)

Go for a supercharger. 280bhp should be easy to obtain this way, all be it a little bit expensive. You will however end up with a car that will eat 330's for breakfast and in terms of bottom end/mid range grunt will be quicker than an M3. You will need bigger brakes and beefed up suspension as well though.

If someone was fitting a Super or Turbo charger, I would expect a remap as part of the job!

Peter Fenwick wrote: brybusa wrote: See, Star fury, itll do it, you just need Peters mechanical lack of sympathy...! Lack of mechanical sympathy! WTF. The 328 engine does not redline till 6200rpm. Occaisionally taking a cars engine to the redline and slightly beyond does not display a lack of mechanical sympathy. The engines are designed to be able to take it and infact multivalve engines are designed to be revved. After all whats the point of having variable timing that doesn't come in till 4K then changing up at 5k.

Calm down Peter!

As you said you wouldnt normally rev the car that hard and I wasnt implying you did, but to achieve 60in 2nd you took it past its normal peak power point where you would naturally change up IE , a litlle bit of mechanical unsympathy!!

And I agree it doesnt "hurt" a well maintained car now and again..

the 'busa ran to 125 in second , with some wheelspin on the change into 3rd(which is good for an indicated 150MPH)..and near as damit double the MPG of the 535 for an "extra" journey speed of between 30 and 90MPH ..Figure that one out!

Starfury wrote: Eh?

What part of my post caused you to proclaim "eh?" SF