|
In Reply to: Agreed again, partially... posted by Joe on January 15, 2000 at 18:10:12:
I wanted to my .02 regarding weight: From my days as an SCCA racer, the simple formula that we used is that 1 lb of unsprung weight is like 2 lbs of sprung weight. That is: adding 1 lb to your wheels/tires is basically equivalent to adding 2 lbs inside your car. Obviously the 850's are so heavy to begin with that this may not make a noticable difference, but always remember that the most important factor in any car is power-to-weight ratio.
That said, are there any recommendations for a 17" wheel with a simple 5 spoke pattern for my '92 850i automatic? I most probably will put P7000's on it (P-Zero's wear too fast for my everyday use). Thanks. - SRC
: Well, for one, the new 750, and the later model 850s have VERY tough suspensions, so I stand corrected on my original post. ON THESE particular cars, I 'suppose' that a 53 percent weight gain could be within tolerance. Keep in mind that you must add tires, and that your "loose" or unsprung suspension components are also factored in when the car rises over small lifts in the road at speed. This is why BMW added the ALUMINUM contol arms on later models. (WHICH by the way are FORGED.) Also, you will notice EXTREME differences in Hamann, OZ and even SCHNITZERs offset "opinions of what will fit your car.
: EXAMPLE- My e24 took a 22 mm offset rim stock, but Hamann's HM2 for my car was a 13mm. Yes, a SMALL difference (2-3mm) is okay, but 9 is WAY off! Sorry. The fact is, a stock e24 wheel is 19 lbs, and a little over 15 inches(metric).
: On an OLDER E31, the suspension can't take a 30% weight gain. On a newer one, sure, they might not wobble. HOWEVER, Newton tells us of objects tendency to stay in their original motion. The heavier the object, the more force the steering, suspension, etc. must place on it to overcome its directional change versus weight, etc. TRUST me lighter is MUCH better.
: As for offset, the camber can be tweaked to accomodate for the differences, but original handling characteristics will be ruined, unless you get really lucky.
: BMW makes some heavy wheels because they cost less to make, and people like how they look. HOWEVER, most Bimmer rims are designed well under 21 LBS.
: Joe
© 1997 -
2009
Jump Internet Inc. All rights reserved.
