Convertible M3 Vs. Coupe M3

[codizle915]

What could make the convertible as light and as fast as the coupe?

I hear so many stories about how people hate the convertible, they say its for the speed difference but i feel it could be drastically changed with the right parts. I'm also wondering if its the roof itself or the mechanism to take it down that makes the convertible so much heavier?

[smiwi]

As many have said - you don't buy the convertible if you want max performance. I have an e93 and love it - performance is more than you can really use in most situations. If you are not taking it to the track, the vert is a great tradeoff of power, style and sun...

Originally Posted by codizle915

What could make the convertible as light and as fast as the coupe?

I hear so many stories about how people hate the convertible, they say its for the speed difference but i feel it could be drastically changed with the right parts. I'm also wondering if its the roof itself or the mechanism to take it down that makes the convertible so much heavier?

[Pimp Star]

The roof isn't that much heavier. It's the things that make the roof go up and down and the extra bracing that goes into making a convertible as close to the coupe and sedan as possible. The E90 Sedan is even more rigid than the coupe and pre-facelift was even lighter, but they are nearly identical around a track. The E93 is behind, but only when compared to the other 2 M3's. It is still a powerhouse.

[FStop7]

Living in LA is a pretty good argument for getting the convertible.

[ooowowizstev]

I believe I read an E93 is roughly 400 lbs heavier than an E92. And its true, doesn't really matter if you aren't planning to track it. Sometimes I wish I had an E93 instead. Its hot out here in LA and I think I'd have a better time cruising PCH with an E93.

[dhoggm3]

They are all beasts on the track, but you'll be hard pressed to find one where you can track the E93. For me the great equalizer was the AA exhaust and pulley. I think with a little ECU work, it will be 400lbs gone!

[330CIZHP]

The roof itself is just one part of what contributes to the extra 400 lbs weight. Since there is no roof present over the car that in general contributes greatly to the structural rigidity of the car, the structural rigidity of the car is compromised greatly. In order to mitigate that, a lot of reinforcements need to be added in the car to enhance the structural rigidity to compensate for the lack of a fixed roof which contributes to the added weight.

In a nutshell,

M3 sedan and coupe: If you want best performance in M3 (both equal in performance and handling), but you will not get that open air experience with sunshine in your face.

M3 Convertible: If you are willing to give a substantial amount of performance/handling for the added 400 lbs and structural rigidity to gain the open air experience, sunshine in your face and listen to the exhauste note blaring.

Considering how much the convertible costs more than the sedan and coupe, if you spend more money just to equal the performance and handling of the stock coupe or sedan then it will be a lot more money spent on the car compared to the coupe/sedan for the open air experience. It is really your money at the end of the day so it is your call.

[fpblue]

I've had both. Unless you are going to track the car, the difference in handling is hardly noticable. Yes it will be slower, but still faster than 95% of the cars on the road. Unless you are drag racing, I don't see the big deal of a little slower times.

If I lived in California, I would get the vert without question. If the weather is above 40 degrees I drop the top. I really miss the open air feeling of a vert. It is worth the extra dough.

Personally, I wouldn't mod. I am always scared of warranty issues. If I had to mod, I would do the Dinan stuff.

Good luck.

[pmeloche]

I have an E90. I pull down all four windows and open the sunroof et voila an E93 with all the benefits of an E90.

[fpblue]

Originally Posted by pmeloche

I have an E90. I pull down all four windows and open the sunroof et voila an E93 with all the benefits of an E90.

That is how I talked myself into my E90. It's not the same though. I miss the open air. I'm also moving back to NY, so I can use the vert more than I can in Wisconsin. That said, the E90/92 are awesome cars.

[JCtx]

I've had 2 verts, and I'm done with them; the negatives outweigh the positives IMO, especially for somebody afraid of skin cancer. A moonroof is the best compromise for me indeed .

[Finnegan]

I have an E93.

I don't have much to add since folks have covered this topic so well except that going with more "stripped" E93 will save some weight. DCT adds about 60 pounds, Premium Sound about 20, EDC 10, Nav 12. That's 100 pounds. But even with those reductions the car will still outweigh the E92 and E90 significantly--you can't get around that.

One buys the E93 because they want the open air experience and because they want pretty much the best vert on the planet. Make no mistake, the car has a good amount of power and handles very well. IMO it handles better than my E92 335 (balance, feel, communication to the driver) but its much slower (my 335 had a piggy). I enjoy driving my M3 much more and I feel more connected to it as a driver.

BWM did a great job "hiding" the E93's weight but you can't get around the physics of the additional weight no matter how well engineered it is. If you're after max performance, want to track it or do autocross, go with the E90 or E92.

It all depends on what your goals and objectives are....and only you can answer that.

[foosh]

I'm just wondering why amateurs constantly think they must know more than highly-experienced automotive designers and engineers.

Yes, you CAN make it lighter by cutting out a bunch of structure which serves to make up for the missing roof. However, I wouldn't recommend that you either own or drive it after that.

[djMpower]

As others have said, it's not the roof that makes it heavier it's all the extra structural support inside of the body panels of the car. Frankly I don't think you would be able to remove those without seriously compromising the structural rigidity of the vehicle. Plus, what would you really gain? It's only a difference of .1 to 60 and a second or two at the track. Unless you're planning on entering the BTCC with it I'd just leave it be.

[SlammedR8]

Originally Posted by pmeloche

I have an E90. I pull down all four windows and open the sunroof et voila an E93 with all the benefits of an E90.

Not even close my friend, not even close. Because I can drop all 4 windows in my E93 and leave the roof closed and it does NOT sound anywhere near as good as when the roof is actually open. The sound tinkles in the back of your head. Its undescribale.


OP, if your a "convertible guy", then go for it. If your not, then get the E90/E92. Its really that simple, I think the weight and all the other bs is worth having the feel of a convertible.
I recently sat down for a dinner with a few friends and there was an older gentlemen there who owns a 2007 Ferrari F430 Spyder. He said he would never buy a non-convertible exotic, because there simply isn't anything like hearing the sound and feeling the air pass through the cabin. Especially when talking about high-end cars, (like a 430), your only going to drive the car on nice/warm days; therefore might as well get the full experience with a convertible!

[drey]

What could make the convertible as light and as fast as the coupe?

Cut the top off of your E93 with a chain saw.

[MrHarris]

If you do full bolt-ons, you'll probably end up being faster than an E90/E92.

[Atny286]

It's all about what you prefer in a car. all M3s are pretty much the same for someone's 'first' M3. The roof top causes the weigth balance to swift when open or closed. Also it's less balanced then the E90/92, however only noticable for an experienced (M-) driver.

Since I hate doing 150mph with top open, I prefer E90/92. Also I'd like to have comfort access to the back seats... I drive a sedan

[M3 vert]

Originally Posted by slammedm3

Not even close my friend, not even close. Because I can drop all 4 windows in my E93 and leave the roof closed and it does NOT sound anywhere near as good as when the roof is actually open. The sound tinkles in the back of your head. Its undescribale.


OP, if your a "convertible guy", then go for it. If your not, then get the E90/E92. Its really that simple, I think the weight and all the other bs is worth having the feel of a convertible.
I recently sat down for a dinner with a few friends and there was an older gentlemen there who owns a 2007 Ferrari F430 Spyder. He said he would never buy a non-convertible exotic, because there simply isn't anything like hearing the sound and feeling the air pass through the cabin. Especially when talking about high-end cars, (like a 430), your only going to drive the car on nice/warm days; therefore might as well get the full experience with a convertible!

+1
Slammed nailed it right there!

I agree 100%, open-air motoring and hearing that V8 growl...is just priceless.
Plus, you spend more time on the road then on the track...

[Green///Hell]

Yeah but the F430 argument is totally different and I find it to be irrelevant
The Spyder is almost just as good as the coupe performance and handling
Same can be said for Lamborghini, but in the case of BMW/Porsche the Verts are just not as good as the coupes theres no comparison

Where as in the exotics mentioned you would have to be a pretty well trained racing driver to milk the extra tenth of a second of the coupe over a spyder. In the E93 there's just no getting over that hump. It's really for looks and for sunshine comfort which is why you buy it, if not the owners would just get a GT3 or other comparable sports car.

Exotics have to be looked at car by car. You cannot just generalize that all verts are going to have that big of a gap over their coupe counterparts but in the case of the E9x coupe/Sedan are better performance no matter how you put it. Even if you were to make it better in a straight line, the track handling still wont be all there.

Theres a reason why SL Black Edition went with a fixed roof and Bugatti Veryon Vert is slower than the coupe version

[quality_sound]

I'd go with a vert in a heartbeat if it had a 4-door option. I'm tired of dealing with long doors in small parking spots and my kids climbing in and out.

[mkoesel]

Originally Posted by codizle915

What could make the convertible as light and as fast as the coupe?

You'd really have to gut the car, I think. Probably removing most non-essential interior parts, convenience features, and sound deadening - similar to what you'd do for a dedicated track - car would do it. But then you'd end up with a pretty non-livable daily driver.

I hear so many stories about how people hate the convertible, they say its for the speed difference...

I'd go drive one before you make any conclusions yourself. A lot of people who complain outright about the weight are people that don't actually own the car. Most owners are very happy with the car from my experience.

...but i feel it could be drastically changed with the right parts.
I'm also wondering if its the roof itself or the mechanism to take it down that makes the convertible so much heavier?

I don't have much to add to what others said. I agree it is the additional chassis bracing that probably accounts for most of the weight. I don't think the "adding lightness" philosophy is necessarily the best way to go for making the vert faster. You're probably better off doing engine mods if you want the car to accelerate faster. If having the best handling car is your goal, then I think you'd be best off with the coupe or sedan, IMHO.