Snowmaggedden is over for now

The snow has abated and now comes rain to melt it...all at once. We had abut 20 inches of snow over the past 6 days and had to shovel the driveway every evening after work.

Due to low ground clearance, had to park the BMWs and drive the 3/4 ton Suburban.

Bob in Lake Havasu

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Bob in Everett
The snow has abated and now comes rain to melt it...all at once. We had abut 20 inches of snow over the past 6 days and had to shovel the driveway every evening after work.

Due to low ground clearance, had to park the BMWs and drive the 3/4 ton Suburban.

Hey Bob, I heard you guys where getting dumped on this last week, unusual, right?, wonder how Peter is doing. We're getting a few inches tonight and tomorrow here in 11930 but it's been such a mild winter so far. Just winterized the bikes a few days ago and now, we wait it out....

Cheers, Rick

I was an unusual accumulation over several days. I was able to get around with the studded snow tires on the Suburban but the snow plows were not going on side streets so the first 100 feet tomorrow will be a challenge. I hope the rain melts a lot of it by then.

We are headed for a BMW club event at TC motorsports for a demonstration on suspension set up. It is a 1.5 hour drive from Everett so we have to get an early start. Afterward is a lunch gathering social event for the club members willing to venture out in mid Winter. Should be fun.

Bob in Lake Havasu

Winter is skipping a year, so it seems. At least where I live. I can only express the thickness of snow in millimeters (about 2 mm). Good for heating costs, worse for winter driving pleasure.

Enjoy the snow and keep it safe!

I'm just a couple of hundred km north of Bob and missed getting dumped on.

However; only 20km east of where I live; they have experienced everything from blowing drifting snow with accumulations to 10" or more. White-outs, freezing rain, extreme cold( -16deg C) and high winds(100kmh) have made it a living hell for people having to drive.

There was a maximum of 1" on my driveway and for the most part, the roads in the greater Vancouver region were clear and bare...dodged another bullet

Hey Bob, I'd be interested what the "demonstration on suspension set up" was like if you made it.... My brother has a suburban and it's a brute in the snow.

Hey Peter, seems like you caught a break, this time. The new car should work well in the white stuff, yes?

We just got 6 inches or so of snow but tomorrow it's going to be 50 tomorrow so maybe I'll get my car in to the garage for a new fan clutch, the nose of it anyway

Cheers, Rick

The demo was held at TC Motorsports. I was surprised to see almost 10 percent of the Pro3 cars in the shop for some kind of work in preparation for the upcoming racing season. There were two Miata race cars and 5 E-30 Pro3 cars in the shop. The demo was to showcase the equipment they use to set up the suspension of the cars. They have a rack with scales under each tire that are wireless transmitters to the control panel so the weight on each corner of the car can be seen at once. The car is weighted to simulate the driver and fuel load as it would be set up for a race. Suspension and weight adjustments are made to get as close as possible to the desired 50-50 balance front to back as well as the preferred balance for a particular track. Also they set up the caster, camber and toe to what the car owner wants for the track.

They will do installs of all the popular aftermarket stuff to make the normally not adjustable BMWs have some.

The springs are another item that they adjust for handling properties. One of the club members asked what the ideal spring rate was for the E-30 and they said it was proprietary. I was also surprised to learn how the shocks are adjusted to affect the handling of the car.

The one parameter I have not quite understood is the tire pressure and its effect on oversteer and understeer. The list they gave us said the opposite of what I had thought before.
I have been trying to sort out my snow tires handling as they are quite different from the summer tires.

Bob in Lake Havasu

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Bob in Everett
The springs are another item that they adjust for handling properties. One of the club members asked what the ideal spring rate was for the E-30 and they said it was proprietary.

That's BS. Different spring rates will be best suited for different styles of driving, and whether a driver prefers more or less oversteer, but there is certainly an optimal range with nothing "proprietary" about it. A quick look at Spec E30 specs would turn up what is required in that series, and I'd bet a glance at some online forums would turn up preferred adjustments to that spec in no time. I run a track-prepared Miata, and optimal track spring rates in those cars are pretty well agreed upon at around 600-700 lbs. front and 300-375 lbs. rear.

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The one parameter I have not quite understood is the tire pressure and its effect on oversteer and understeer. The list they gave us said the opposite of what I had thought before.
I have been trying to sort out my snow tires handling as they are quite different from the summer tires.

Oversteer and understeer is roughly determined by relative amounts of traction front and rear. Adding front traction and decreasing rear traction will favor oversteer, while decreasing front traction and increasing rear traction will favor understeer. From any given starting point, you can affect understeer and oversteer by adjusting the realtive grip levels. The greatest contributors to this are spring rates and sway bar (i.e. anti-roll bar) stiffness, but tire pressures (and hardness and tread) will affect it too. There's a popular misconception that lower tire pressure = more grip, and I sometimes see people letting air out of their tires to "get more grip." But it's not that simple. For any given track condition and tire, there's an optimal tire pressure that will give the best traction, and higher or lower pressures will reduce traction. However, overflation has a greater impact on traction than underinflation, which is where that misconception comes from.

Clear as mud?

__________
Dave
'91 325iX