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Who told you that it "cuts aero drag enough to make up for the 35lbs."? That is absolutely not true.
English BMW magazine that I have around here somewhere from the 90's. I don't remember the exact numbers, but the 325 Sport sold in England and other parts of Europe with the M-technik II panels has a drag coefficient that is 1/100 higher than the E30 M3.
English BMW magazine that I have around here somewhere from the 90's. I don't remember the exact numbers, but the 325 Sport sold in England and other parts of Europe with the M-technik II panels has a drag coefficient that is 1/100 higher than the E30 M3.
What evidence do you have to the contrary?
That's pretty interesting. If you find the article maybe you could post it? I have a complete M-2 kit ready to be installed. When I picked it up the thought of slowing my car down by putting the extra weight onboard did cross my mind.
That's pretty interesting. If you find the article maybe you could post it? I have a complete M-2 kit ready to be installed. When I picked it up the thought of slowing my car down by putting the extra weight onboard did cross my mind.
If I can find it I will. Do you have the factory kit? Maybe you could weigh the parts for us. I put my kit on 10 years ago and I did not weigh them. The 35 lbs was just a guestimate from memory. I could be way off.
English BMW magazine that I have around here somewhere from the 90's. I don't remember the exact numbers, but the 325 Sport sold in England and other parts of Europe with the M-technik II panels has a drag coefficient that is 1/100 higher than the E30 M3.
What evidence do you have to the contrary?
Intuition and fluid dynamics understading. I believe that it could shave .01 off of the drag coefficient -- that is not unheard of. I HIGHLY doubt it provides a lower drag coefficient than an m3. If that were the case, why would BMW have gone through the effort of redesigning the car for racing when they could just throw some mtechnic body panels. But making up for it's weight is another story. It surely has an adverse effect in acceleration, driving at all times except for very high speeds, and it would decrease cornering forces. It would just plain slow you down.
How much time on a track do you spend going 100+ relative to the time you spend braking, cornering and accelerating under 100 mph?
Intuition and fluid dynamics understading. I believe that it could shave .01 off of the drag coefficient -- that is not unheard of. I HIGHLY doubt it provides a lower drag coefficient than an m3. If that were the case, why would BMW have gone through the effort of redesigning the car for racing when they could just throw some mtechnic body panels. But making up for it's weight is another story. It surely has an adverse effect in acceleration, driving at all times except for very high speeds, and it would decrease cornering forces. It would just plain slow you down.
How much time on a track do you spend going 100+ relative to the time you spend braking, cornering and accelerating under 100 mph?
I think I said that the 325 Sport has a higher drag coefficient than the M3. From my shakey memory the stock E30 has a drag coefficient of 0.38, the 325 sport 0.34, the M3 0.33---but I can't find that source, so don't count it as gospel. The E30 M3 needed larger brakes, and larger fenders to fit larger rubber. They also needed to clean up the air flow over the rear of the car so that the rear wing actually did something---I'm not sure the M-tech II rear wing does much of anything--some might argue that it doesn't even look good.:-)
True enough that any weight has an adverse effect on acceleration and its going to slow you down in slow speed corners. But if the weight offers some aero stability, it can also help in higher speed corners. I spend most of my on track time above 60mph, my average speed at PIR is about 80 mph, a little higher at Thunderhill. Still no way to make up for 35 lbs?
If I can find it I will. Do you have the factory kit? Maybe you could weigh the parts for us. I put my kit on 10 years ago and I did not weigh them. The 35 lbs was just a guestimate from memory. I could be way off.
Kurt
I do have the factory kit minus the trunk spoiler (which I didn't want) I will try to weigh before install. I am certain that it will slow the car down but looks count too.
Took the car into the shop today for M-Tech II install. Weighed the parts on the bathroom scale before delivery, accuracy not 100%:
Front valance 3.25 lb
Front bumper cover 3.0 lb
Rear assembly 21.25 lb
Side skirts for vert (both sides) 17.0 lbs
Took the car into the shop today for M-Tech II install. Weighed the parts on the bathroom scale before delivery, accuracy not 100%:
Front valance 3.25 lb
Front bumper cover 3.0 lb
Rear assembly 21.25 lb
Side skirts for vert (both sides) 17.0 lbs
Wow, I didn't remember the rear assembly being that heavy. That IS going to slow us down. The rear wing is heavy too, as it is a pretty solid piece. I'm sure it weighs over 5 lbs. So almost 50 lbs for the complete kit and there are a significant number of fasteners that add up too.
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