300e-VS-VW jetta - Page 2 - PeachParts Mercedes-Benz Forum

pentoman · #16 05-22-2002, 01:39 PM

Not really.. no

Besides, I don't mean 'revving up'.. just loading up the torque converter.. there's a difference.

later

Russ

blackmercedes · #17 05-22-2002, 02:09 PM

Quote:

Originally posted by johnp123
dood, Braking and reving it up is the worst thing possible for your car i'm not doing it and i would advise you not to do it.

Dude,

You, of course, are right. However, it really is his only hope of giving the VW a serious run for his money.

It is very hard on the transmission and final drive unit, as well as the brakes. Given the age of your car, something might break.

But, that's the chance you take when street racing...

blackmercedes · #18 05-22-2002, 02:12 PM

Quote:

Originally posted by pentoman
Besides, I don't mean 'revving up'.. just loading up the torque converter.. there's a difference.

Maxing the converter at full stall speed and then letting the car go is hard on the tranny and driveline. Not so bad for the engine, but creates lots of heat and pressure on the tranny.

Now, after launching our C36, I was surprised at the high stall speed of the converter, but I'm sure the 300E is lower, so the strain won't be as bad...

pentoman · #19 05-22-2002, 02:17 PM

What exactly do are you meaning when you talk about stall speed?

#20 05-22-2002, 03:54 PM

Stall is the speed at which the torque converter will hold the engine speed and not allow further gain (i.e., the engine "stalls"). The key word here is engine. The speed at which stall occurs with a given converter is a function of engine peak torque.

pentoman · #21 05-22-2002, 03:58 PM

uh huh.. I haven't had mine rev to even 1800 rpm, guess common sense kicks in at that point?

later

Russ

#22 05-22-2002, 04:15 PM

A few weeks ago, I raced (very rare occurence) a Jetta VR6 (looked to be almost new) and easily beat it.

It was a college kid that I pulled up next to while driving through the UW-Madison campus with my wife en route to the Asian grocery store.

In the first second or so, he had a small lead, but after I got all the wheel-spin and drama under control, I pulled nearly a car length in front of him -- at about 50 mph. We had to slow down because of traffic up ahead. I wasn't in my Merc, but in a '70 Olds Toronado GT. Factory rated @ 400hp/510 ft. lbs of torque (gross rating, not net

so it's more like 330-350 hp) and it has a stall speed of 2500 RPM. The car also weighs 4600+ lbs. Not bad for an old heavy beast, with 135k miles on an untouched engine. It's hard to get a good launch in the thing, due to wheelspin- which can go on for 30 feet if you really let it loose. It's the second time I've raced it -- it's not that fast when compared to the 442, GTO or any pony car, not to mention many late model cars, due to it's size and inefficiencies.

ke6dcj · #23 05-22-2002, 04:25 PM

What do you think the stall speed of the C36 is, esp. with a high torque peak (I think 4500 RPM)?

Thanks,
:-) neil
1988 360TE AMG
1993 500E

pentoman · #24 05-22-2002, 04:51 PM

Heh.. burning up students in '70s Oldsmobiles on the way to the Grocery store.. :p , sounds quite amusing. Did it impress the wife?

It never impresses passengers of the A8 Quattro much to launch without warning them first - a 300hp V8, Four wheel drive, and light(ish) aluminium construction mean some pretty scary 0 - 15mph runs

It's always made me kinda worry about powerful rear-drive sedans, just spinning away all the power. Is it frustrating?

Russ

carman850 · #25 05-22-2002, 05:11 PM

You are asking 400E owners with 195 stock tires, aren't you?

#26 05-22-2002, 05:11 PM

Russ,

The Toro is front wheel drive.

After the 1936 Cord, it was the first US production car to have this feature in it's 1966 debut. Front wheel drive is not popular with the muscle car or race crowd for obvious reasons. But to the uninitiated, it surprises the heck out of people.

The wife wasn't impressed at all. More embarrassed because of the tire squeal and roar of the 455 -- she tried to get my goat by saying the Jetta driver probably would have won if he would have shifted correctly. Ehh whatever...

The A8 is a great car. I've driven the 300 hp A6 and was quite impressed -- deceptively fast.

blackmercedes · #27 05-22-2002, 06:30 PM

Actually, stall speed is a function of the construction and diameter of the torque converter. When I was drag racing, we constantly tinkered with stall speeds by switching converters. It's "slip."

Neil, we found our C36 stalling in the high 3K/low 4K rpm range. Brake torquing the car resulted in some wicked launches, but not something I'd do on the street! That is a high stall speed for a street sedan, but the AMG boys wanted the ability to generate numbers. If only they'd put a REAL ASR off switch in...

One nice thing about the AMG sedans is the lack of wheel hop. I watched an E55 ripping off mid 13's at 107, and it looked so easy. The IRS allows the car to hook up very nicely. I've seen so many Mustangs and Camaros whipping their live axles into a wind-up frenzy.

The easiest car I've ever sent away from a Christmas Tree is a 911 Turbo. Hold the revs at about 3500, and dump the clutch. The car just digs in and torque does the rest. I'm not sure if I could get any car across an intersection quicker! The rear-engine layout is amazing for straight line acceleration. Braking is unreal in those cars too. Thanks to the wonky weight distribution, the rear brakes really get a work out. Having four contact patches, including rear wide-meats, makes a huge difference.

#28 05-22-2002, 07:21 PM

[QUOTE]Originally posted by blackmercedes
[B]Actually, stall speed is a function of the construction and diameter of the torque converter. When I was drag racing, we constantly tinkered with stall speeds by switching converters. It's "slip."

Yes, but my def'n isn't incorrect. Simply put, stall converters are desirable because they can deliver the maximum torque from the engine to the transmission from a dead stop.

pentoman · #29 05-22-2002, 07:39 PM

Quote:

Originally posted by w126
Russ,

The Toro is front wheel drive. After the 1936 Cord, it was the first US production car to have this feature in it's 1966 debut.

Jeez.. what were they thinking?!! It certainly surprises me!

Quote:

The A8 is a great car. I've driven the 300 hp A6 and was quite impressed -- deceptively fast.

Yep. But it's very b--i--g. Best thing about it is the quality - you certainly don't find anything like that in a new MB.

Russ

#30 05-22-2002, 07:50 PM

Quote:

Originally posted by pentoman

Jeez.. what were they thinking?!! It certainly surprises me!
Russ

It was more or less a marketing move by Oldsmobile to draw attention to their division. (Now Olds is dead) Engineers had been working on the design since the late 1950s. The FWD trans was essentially a TH-400 mounted along the driver's side of the engine. The TH-400 (redesignated the TH-425) was split aft of the torque converter, the transmission itself was reversed and mounted along side the block with the output shaft facing forward. The chain drive couples to two halves together.

The torque converter is mounted on the flywheel in its normal location at the rear of the engine and a massive chain drive couples the engine to the trans. The differential is mounted at the end of the trans (about under the #3 spark plug), with the right side half shaft running under the oil pan.