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101N on the way to Calabasas came across a brand new 7-series BMW (that flew past me earlier heading on 405N) and a CLK430 coupe.

Already in front of the 7 (we weren't racing yet) I proceeded to pass the CLK430 in the fast lane but slowed a bit as I inched past to see if he would bite (we all were already almost going 90). He did and started to accelerate past me quickly. I leisurely dropped to 5th gear and instantly pulled.. he gave up after I got a couple car lengths. Before anyone asks.. yes, he was trying.. it was obvious.

The 7 had been pacing me all the way to near the Woodlake exit, I began pulling over and slowing to get off at Mulholland/Valley Circle. At the same time he pulled even with me in the fast lane and slowed. Knowing it was on, I passed my exit and gave a little push forward (still in 6th gear). He bit and got on it.. again.. I dropped to fifth and immediately pulled away. I wasn't floored cause I wanted to hit the Calabasas Rd exit 1 mile up, but he still couldn't catch up.. though I wasn't pulling on him either.. those things have long legs it seems.

2 fun kills on the way home.

Here's the wierd part.. as I was braking to get off the freeway, I felt a strange pulsing of the wheel like the brakes were warped or something.. but it's not like I was on them at all until I got off the freeway, so they shouldn't have been hot. Hmm.. wonder what that was.

bitjockey (bum)

There's one running around town here that'll keep up with my friend's S4 w/ a VM1...

quickersilver

...and the S4's 4th gear is a lot lower than the CLK430's 4th gear. I've raced a few of them from 5-100, and they'll hang with a stock S4 at these speeds, but once you get up above 100, you'll walk away pretty quickly.

CLK430 has a 2.87:1 Final drive ratio, and its 4th gear is 1.00:1 according to Road & Track's April 1999 test, it hits 4th from 101 to 130. It makes 295 ft-lb of max torque, so in this speed range it'll do a max of 295*1.00*2.87 = 846 ft-lbs of torque to the wheels (if you assume a zero driveline loss, which of course isn't the case, but stay tuned); the S4, otoh, has a 4.11:1 final drive ratio (according to Road & Track's October 1999 test), and its fourth gear is good from 100 to 119 mph, with a 0.97:1 ratio.

So, in this speed range, it'll be making max torque of 258*0.97*4.11 = 1029 ft-lbs. That's a huge difference, even with the Quattro's slightly higher driveline losses.

Comparing third gears for the cars shows why the CLK can hang: the cars' gearing/final drive give torque multiplication factors of 5.06 for the S4, 4.28 for the CLK for their third gears, so

S4=258*5.06=1305 ft-lbs
CLK430=295*4.28=1262 ft-lbs

It's odd that Mercedes put such a low fourth gear in the car...

Audiboy

at the speed range they are racing, then use the available torque at that rpm. It'll be dynamic and changing, but it may show at times that they'll be trading spots in max torque at the wheel at that particular rpm

quickersilver

...the S4 makes its 258 ft-lb from 1850-4400 rpm, while the CLK430 makes its 295 ft-lb from 3000-4000 rpm. Given that the S4 redlines at 119 in fourth, while the CLK430 doesn't redline (6000 rpm) in fourth until 130, I'd say they're both in their sweet spots, or close to it, at 100.

Plus, I cooked him when I hit fourth...before that, it was pretty much even; I pulled slightly, but when I hit fourth, he was toast.