software

Interstingly some people seem to think that "euro headers and Cats" make a huge difference to revability engine smoothness and reponse. Any thoughts?

Most people manage to delude themselves that anything they spend lots of moeny on MUST be better, and of course makes WAY more HP.

Euro models doen't really have much more HP if any at all, over the M's we get here in the states..Thanks to overly-populated states such as California, the entire United States has to suffer...

Although I have not dug into it much...I could almost promise that it probably wouldn't make any noticable difference other than bragging rights, and you would probably need to hunt down a Euro ECU as well...

Originally Posted by dawgbone

Euro models doen't really have much more HP if any at all, over the M's we get here in the states..Thanks to overly-populated states such as California, the entire United States has to suffer...

Although I have not dug into it much...I could almost promise that it probably wouldn't make any noticable difference other than bragging rights, and you would probably need to hunt down a Euro ECU as well...

Actually the EPA set the cold start standards.

Actual HP loss is about 5 HP. 343 DIN HP = 338 SAE HP and 333 SAE HP = 338 DIN HP. Or 343 DIN HP - 338 DIN HP = 5 HP or 338 SAE HP - 333 SAE HP = 5 HP. So the real difference is 5 HP.

Apart from power peaks being really close, does the hp and touque curve look the same or similar. Or do euro cars have a wider range of power.

Could be that our cold start standards require the cat to be closer to engine and this type of exaust is more costly to make. Also could be that our exaust has more backpressure affecting power range and making our engines feel sluggish compared to a freer reving euro, or alternativly the performance difference is negilgable.

The CSL did not pack that much more power yet its engine with lighter internals and different exhaust is apprently an animal compared to a regular M3, or maybee its really just the weight loss?

Originally Posted by boxerman

Apart from power peaks being really close, does the hp and touque curve look the same or similar. Or do euro cars have a wider range of power.

Could be that our cold start standards require the cat to be closer to engine and this type of exaust is more costly to make. Also could be that our exaust has more backpressure affecting power range and making our engines feel sluggish compared to a freer reving euro, or alternativly the performance difference is negilgable.

The CSL did not pack that much more power yet its engine with lighter internals and different exhaust is apprently an animal compared to a regular M3, or maybee its really just the weight loss?

Generally Euros do not really produce much more performance over US models...The fact that we cannot have the CSL is the whole problem...The CSL is dramatically lighter and supposedly punches out an additional 30-40 horses(360ish)...If they only made it with a 6spd, it would be even more entertaining..

I think that the differenc between Euro's and US models is probably more along the lines of engine managment and how the fuel is being dumped into the motor, in accordance with the O2 reading in front of the CAT..

Curve is very similar, only peak is 5 HP higher.

And yes, the cold start requires the cats to be IN the headers, which slightly restricts breathing. Euro cats are after the headers. Same flange position from headers to exhaust pipes.

And the cat position is the ONLY difference. Put on the Euro headers and cats, and you get hte 5 HP back. No software required. But for $2K - $3K plus install, it is a very expensive 5 HP.

CSL makes 17 more HP than standard (360 DIN HP versus 343 DIN HP). It does weight a bit less.

Didnt the CSL also have lighter reciprtocating internal mass in the engine, ie lighter conrods, pistons crank etc?

Also isnt fuel a big factor. In europe they have 98 octane. I would imagine that with 93 the computor dials back power, so in ideal situations euro and us might be close, on the street
with our fuel the difference might be greater?

No, different cams, software and intake.

NO, Euro uses RON for gas pump numbers, we use AKI (anti knock index = (RON+MON)/2).

BMW requires that h efuel MON not be lower than 10 points below the RON, and since there is no problem with US fuels, we can assume this to be true.

Euro RON = 98. 98 - 10 = 88. (98+88)/2 = 93 AK*. Hmm, most of US gets 93 AKI as premium.


QED Euro premium and US premium are the same in anti knock properties.

In that M3 , weight is your worst enemy. As the car starts to get lighter you will find its responsiveness get better. Better then any Engine mod would be to put in two light front seats, four light-weight wheels, get rid of the back seats if you don't need them and all the stuff in the trunk that is not needed. Stock battery is quite heavy too. There are some nice after market batteries that put out more power then the stock battery for a lot less weight. You will see that the car responds better and see a good improvement in braking. The CSL in Europe does well mainly because of the weight loss. M3's Are great cars

I agree these things are heavy, one can feel it all around, that is probably why the cars also need relatively stiff springs. Looks like new M3 will also be heavy. I wonder what the previous generation euro m3 felt like. Maybee the new 1 series with the current m3 engine will be a real stormer.

Have felt a big difference as engine begins to loosen more with mileage. Ran car up to an indicated 135 the other day and there was plenty more to go, it sure would be fun to run it hard on an unrestricted road. Anyway with motor full run in the track becons. Sorry to see that BMW CCa events are some type of lottery. Anyone have experience with the SCDA.,