Weight and power to weight ratio

[swamp2]

OK looks like we have a winner 3483 lb curb weight (btw my guess back in 11/06 was 3500 even ). I sure hope the number is solid. IMO this is a fantastic achievement. The 335i weighs in at 3571 this is almost 100 lb lighter!! This is a huge achievement given the things that add weight to the vehicle relative to 335i: chassis stiffening, engine, clutch, rotors/calipers, tires, cooling system, exhaust system, etc.

I think the list of weight savings items other than composite roof and body panels will look pretty darn impressive once we learn about all of the effort that went into this.

Updating my lb/hp list we now have:

• Corvette C5: 8.0
• E60 M5: 8.1
• E92 M3 8.3
• F355: 8.3
• New Carrera S (+20 hp rumored): 8.3
• Carrera S: 8.8
• RS4: 9.4
• AM Vantage: 9.5

Boys with an extra .3-.4 seconds per shift with ZSG we are really going to have a on our hands.

[Kafka]

Thanks Swamp. Excellent info as usual.

It makes me wonder what it will "feel" like to drive (adrenalin rush for sure at least I expect). Do you have any thoughts on the carbon topped cab that will be released a bit later? I have one now (2004 M3) and while it is a bit heavier etc. on the track it is still a joy (and a bit scary at times) to drive. Do you think the newM3 carbon roofed cabs will offer an improvement from the softtops re handling and weight? Given the extra cost of the cabs this is an important consideration.
K.

[M3onTwomps]

Originally Posted by swamp2

OK looks like we have a winner 3483 lb curb weight (btw my guess back in 11/06 was 3500 even ). I sure hope the number is solid. IMO this is a fantastic achievement. The 335i weighs in at 3571 this is almost 100 lb lighter!! This is a huge achievement given the things that add weight to the vehicle relative to 335i: chassis stiffening, engine, clutch, rotors/calipers, tires, cooling system, exhaust system, etc.

I think the list of weight savings items other than composite roof and body panels will look pretty darn impressive once we learn about all of the effort that went into this.

Updating my power to weight list we now have.

• AM Vantage: 9.5
• RS4: 9.4
• Carrera S: 8.8
• New Carrera S (+20 hp rumored): 8.3
• F355: 8.3
• E92 M3 8.3
• E60 M5: 8.1
• Corvette C5: 8.0

Boys with an extra .3-.4 seconds per shift with ZSG we are really going to have a on our hands.

Maybe I'm looking at something wrong, but I've got 8.66 for the Audi RS4 with 420hp and weighing 3,638lbs.

[maq]

You guys' math is off. How can the RS4 have a better ratio than the M3? Assuming both are rated at 420hp, how can the heavier Audi have a better number? Even if the M3 is rated at 414hp, the Audi's extra 6hp can't possibly offset 155lbs of extra weight, can it?

My calculation using the industry standard horsepower per ton:

M3 - 265hp/ton
RS4 - 254hp/ton

[RandyB]

Not with the extra 50 lbs that silly thing will weigh. And you 'boys' better hope for a F430-esque launch control to boot if you plan on getting out on a 6-speed car.

But yeah, I like the weight.

[M3onTwomps]

Originally Posted by maq

You guys' math is off. How can the RS4 have a better ratio than the M3? Assuming both are rated at 420hp, how can the heavier Audi have a better number? Even if the M3 is rated at 414hp, the Audi's extra 6hp can't possibly offset 155lbs of extra weight, can it?

My calculation using the industry standard horsepower per ton:

M3 - 265hp/ton
RS4 - 254hp/ton

Sounds good to me.

I just divided weight by horsepower. In my calculations, the M3 still has a better ratio, but my RS4 numbers were different than Swamp's.

[swamp2]

3957 lb, read past the first hit on google.

[jtown]

The RS4 is a fat pig.

[kyotousa]

Originally Posted by jtown

The RS4 is a fat pig.

maybe compare to the E90 M3

[Robert]

Originally Posted by jtown

The RS4 is a fat pig.

It still performs beautifully. More car than I can handle right now.

[paulyd]

swamp ur rs4 number is off, it can't have better power/weight than the M3.

the car weighs 3957lbs and has the same hp as the M3

[kyotousa]

anyway since the weight is out...anyone gonna guess the 1/4 mile time?

12.8...

[Jason-NY]

Originally Posted by kyotousa

anyway since the weight is out...anyone gonna guess the 1/4 mile time?

12.8...

Well, the RS4 ran a 12.8 @ 109.7 in 8/06 Road & Track with a curb weight of 3920 and 420 HP. The E92 will supposedly weight 442 lbs less with the same power. 12.5 sec ¼mile is my guess.

[GregW / Oregon]

Originally Posted by Jason-NY

Well, the RS4 ran a 12.8 @ 109.7 in 8/06 Road & Track with a curb weight of 3920 and 420 HP. The E92 will supposedly weight 442 lbs less with the same power. 12.5 sec ¼mile is my guess.

I agree, 12.5 at, say, 110-112.

[skierman64]

Some of you guys are reading the power to weight ratio backwards. The lower the number the better. It is really a listing of lbs per hp. Less lbs the better. Which is why the plastic car is listed as the best.

[JEllis]

Yep, he is listing pounds per HP not the other way around. If it was HP per pounds then you would get fractions of HP..DUH!

To but it simply for you idiots (sorry I had a bad day), the smaller the number the better......!!!!!!!!

Jason

[maq]

Originally Posted by JEllis

Yep, he is listing pounds per HP not the other way around. If it was HP per pounds then you would get fractions of HP..DUH!

To but it simply for you idiots (sorry I had a bad day), the smaller the number the better......!!!!!!!!

Jason

I've never seen a lbs/hp ratio in my life. It's called a power to weight ratio, not the other way around (weight to power). So if he called it a power to weight ratio, the power number should be placed before the weight number. The industry standard W/P ratio is measured in hp/T.

It doesn't matter how big or small the number is, you put the BEST number on top when making a list like this. Do you go to the bottom of a list to find the best lap time?

I personally have nothing against the OP, just trying to point out an error. Calling us idiots because we don't think the same way the OP does on this subject (which is neither scientific nor logical) speaks volumes about yourself.

[enigma]

Originally Posted by maq

I've never seen a lbs/hp ratio in my life. It's called a power to weight ratio, not the other way around (weight to power). So if he called it a power to weight ratio, the power number should be placed before the weight number.

Both are equally valid and I have seen both used in a lot of places. As long at the units are listed beside the number there should be no confusion.

[swamp2]

Originally Posted by enigma

Both are equally valid and I have seen both used in a lot of places. As long at the units are listed beside the number there should be no confusion.

Indeed I used lb/hp, the less the better. I should have stated that and given units. However, as enigma said both lb/hp (around 10 for sporty vehicles, nowadays 8...) as well as hp/ton are common. I changed the order and added units per other suggestions.

BTW, all of this should have been pretty obvious. It doesn´t make anyone an idiot but you should be familiar with numbers of about 10 lb/hp.

[esquire]

Originally Posted by JEllis

Yep, he is listing pounds per HP not the other way around. If it was HP per pounds then you would get fractions of HP..DUH!

To but it simply for you idiots (sorry I had a bad day), the smaller the number the better......!!!!!!!!

Jason

"to BUT it simply for you idiots" ??? clearly you're a genius... einstein.
remind me again, how far apart are the 'b' and 'p' keys on the keyboard?

[esquire]

swamp, i'm curious... where did you get the 3483 lb curb weight figure from? i must be missing something, because i haven't seen it in any of the recent posts.

[Epacy]

The weight is real. Actually, can't believe you haven't seen it.