[herbz]

Originally Posted by RiXst3r

so you dont thing that AWD will help in getting all that power to the ground? my 335 spins its tires way too much right now... and even BMW's official 0-60 numbers for the 335xi show it being a few ticks faster to 60, meaning it probably hooks up better, even on dry ground

one word.... tires.

the stock runflats are terrible. get some newer sticky tires, or even better drag radials, and you'll be running your full performance potential without that annoying spinning.

also, AWD adds about 200-300 extra pounds. any performance gain you would get from AWD would be erased by the extra weight.

[bnj]

Runflats are not slow. Drag radials are very slow in wet. In rallying you can see that awd has allocated weight penalty by rules much more than 2-300lb and still 2wd has no chance against awd.

[DrDomer]

Originally Posted by T Bone

I am friends with the guys in service and parts so I wouldn't want them burned for my lust for horsepower....

We will see.....when I test drove the 335i, it was quick enough for me (but not really)....

How many miles do you have on your car? Even if I were to get the procede, it would be towards September / October 2007 when I can get 3000 miles into the car.

I only have 1000 miles. I'll be through break-in by the time I get the Procede. I have driven it fairly gently with a few runs up to 100mph and have gotten it to 6K RPM once. Mostly kept below 5K. I didn't exactly follow a soft break-in, but I didn't "drive it like I stole it" either. The reliability in 3 months of people running the Xede doesn't seem to be an issue in the short term with the Procede. Most importantly, Shiv has 15K miles on his car with around 80 pulls on a Dyno. That is MUCH harder than I'll ever drive the car. So, it doesn't sound like reliability should be an issue as long as your not tracking the car or doing 1/4 mile times every weekend.

[herbz]

Originally Posted by bnj

Runflats are not slow. Drag radials are very slow in wet. In rallying you can see that awd has allocated weight penalty by rules much more than 2-300lb and still 2wd has no chance against awd.

i think we're talking about drag racing in dry weather here, not rallying in the snow.

[OpenFlash]

Originally Posted by DrDomer

Most importantly, Shiv has 15K miles on his car with around 80 pulls on a Dyno.

80? lol... more like 300

-shiv

[Driver72]

Wow, you guys are bickering still about AWD vs. RWD in drag racing.

For people who've owned both, we all know AWD has a huge advantage off the line...(thus usually better 0-60 times)...but to most we pretty much all know that 0-60 is a pretty overrated and single minded performance figure.

Sure, IF you are a stop light racer and just want to see who can go across the intersection faster...AWD cars are for you.
IF you live in rainy or snowy weather...AWD cars have an advantage, though you have to be utterly foolish and moronic to "race" in rain or snow.

But, IF the race starts at anything OTHER than a dead stop or really low speeds, RWD clearly has the advantage as it WEIGHS LESS, and has LESS drivetrain losses...therefore more power gets to the driven wheels in RWD cars.

IF you live in wide open spaces and choose to race into triple digit speeds, AWD has a HUGE disadvantage.

With my AWD cars, at the dragstrip, I could OFTEN beat much more powerful RWD or FWD cars to the 60 foot mark and often even to the 330 or even 660' mark...however...they would ALWAYS be reeling me in, pass me and go onto win the race.

There were even times where I could get a big enough jump on them and hold them off until the 1/4 mile stripe by a fender or so in a sense "winning" the drag race, but having a 1-5 mph slower trap speed.
I knew FULL well, that I won SIMPLY because of my AWD launching advantage (and possibly better driving skills) but also knew FULL well THEY had the faster car.

There IS a reason dragsters are RWD and not AWD too.

What it simply comes down too is a 335xi will probably jump a 335i off the line and "win" the "I beat you across the intersection" race, but the 335xi has zero chance much past that and from a rolling race at any speed above 10 mph it will also lose. AND, even from a dead stop, the 335xi will lose ANY race to a 335i if the race goes past 70 mph (of course again this is in the dry...the only conditions a risky person would even consider racing in).

But BOTH are excellent cars and to each there own.

[bnj]

Originally Posted by herbz

i think we're talking about drag racing in dry weather here, not rallying in the snow.

I can see that. Howewer, have a look at the first post. This thread is not about drag racing in dry.

[DrDomer]

Originally Posted by shiv@vishnu

80? lol... more like 300

-shiv

I guessed... I remember you posting that somewhere but couldn't find it. That just reinforces my point more. :rocks: BTW... that's rediculous.

[herbz]

Originally Posted by bnj

I can see that. Howewer, have a look at the first post. This thread is not about drag racing in dry.

true. i was just responding to someone who asked about whether AWD would help getting power to the ground. the answer is yes, it would increase 0-60 times. instead of having power delivered to only the rear 2 wheels, it's distributed to all 4, therefore equally distributing 1/4 of the power to all 4 wheels, as opposed to 1/2 of the power to the 2 rear wheels. that would make getting initial traction alot easier.

upsides of AWD
-great in the snow
-balanced chassis (mid engined AWD Porsche anyone?)
-would increase handling ability compared to RWD, if the RWD and AWD version were the same weight.

the downsides is that
- launching an AWD car is more stressful on the drivetrain than launching a RWD car.
- added weight of AWD offset any real performance gain when compared to a normal RWD 335i.

an RWD 335i can be just as fast as an AWD 335i at the drag strip with the right tires.

[T Bone]

Originally Posted by Driver72

Wow, you guys are bickering still about AWD vs. RWD in drag racing.

Hey Driver72, I think most people agree with what you posted. My question that I have not been able to find an answer for is how BMW X Drive works versus the Audi Quattro.

Does Xdrive sap power like Quattro at high speed? I was under the impression Xdrive can completely disengage the front wheels so there is no parasitic losses at high speed.

If this is the case, the only difference in performance between the RWD and XI would be the extra 220 pounds....at high speed, this is much less an issue for acceleration.

[herbz]

Originally Posted by Driver72

Wow, you guys are bickering still about AWD vs. RWD in drag racing.

For people who've owned both, we all know AWD has a huge advantage off the line...(thus usually better 0-60 times)...but to most we pretty much all know that 0-60 is a pretty overrated and single minded performance figure.

Sure, IF you are a stop light racer and just want to see who can go across the intersection faster...AWD cars are for you.
IF you live in rainy or snowy weather...AWD cars have an advantage, though you have to be utterly foolish and moronic to "race" in rain or snow.

But, IF the race starts at anything OTHER than a dead stop or really low speeds, RWD clearly has the advantage as it WEIGHS LESS, and has LESS drivetrain losses...therefore more power gets to the driven wheels in RWD cars.

IF you live in wide open spaces and choose to race into triple digit speeds, AWD has a HUGE disadvantage.

With my AWD cars, at the dragstrip, I could OFTEN beat much more powerful RWD or FWD cars to the 60 foot mark and often even to the 330 or even 660' mark...however...they would ALWAYS be reeling me in, pass me and go onto win the race.

There were even times where I could get a big enough jump on them and hold them off until the 1/4 mile stripe by a fender or so in a sense "winning" the drag race, but having a 1-5 mph slower trap speed.
I knew FULL well, that I won SIMPLY because of my AWD launching advantage (and possibly better driving skills) but also knew FULL well THEY had the faster car.

There IS a reason dragsters are RWD and not AWD too.

What it simply comes down too is a 335xi will probably jump a 335i off the line and "win" the "I beat you across the intersection" race, but the 335xi has zero chance much past that and from a rolling race at any speed above 10 mph it will also lose. AND, even from a dead stop, the 335xi will lose ANY race to a 335i if the race goes past 70 mph (of course again this is in the dry...the only conditions a risky person would even consider racing in).

But BOTH are excellent cars and to each there own.

truth

[bnj]

Originally Posted by Driver72

Wow, you guys are bickering still about AWD vs. RWD in drag racing.

For people who've owned both, we all know AWD has a huge advantage off the line...(thus usually better 0-60 times)...but to most we pretty much all know that 0-60 is a pretty overrated and single minded performance figure.

Sure, IF you are a stop light racer and just want to see who can go across the intersection faster...AWD cars are for you.
IF you live in rainy or snowy weather...AWD cars have an advantage, though you have to be utterly foolish and moronic to "race" in rain or snow.

But, IF the race starts at anything OTHER than a dead stop or really low speeds, RWD clearly has the advantage as it WEIGHS LESS, and has LESS drivetrain losses...therefore more power gets to the driven wheels in RWD cars.

IF you live in wide open spaces and choose to race into triple digit speeds, AWD has a HUGE disadvantage.

With my AWD cars, at the dragstrip, I could OFTEN beat much more powerful RWD or FWD cars to the 60 foot mark and often even to the 330 or even 660' mark...however...they would ALWAYS be reeling me in, pass me and go onto win the race.

There were even times where I could get a big enough jump on them and hold them off until the 1/4 mile stripe by a fender or so in a sense "winning" the drag race, but having a 1-5 mph slower trap speed.
I knew FULL well, that I won SIMPLY because of my AWD launching advantage (and possibly better driving skills) but also knew FULL well THEY had the faster car.

There IS a reason dragsters are RWD and not AWD too.

What it simply comes down too is a 335xi will probably jump a 335i off the line and "win" the "I beat you across the intersection" race, but the 335xi has zero chance much past that and from a rolling race at any speed above 10 mph it will also lose. AND, even from a dead stop, the 335xi will lose ANY race to a 335i if the race goes past 70 mph (of course again this is in the dry...the only conditions a risky person would even consider racing in).

But BOTH are excellent cars and to each there own.

I think there is not much different opinions of which one would be quicker in quarter mile. There is not much difference, probably most of the difference is based on how succesful the rwd launch happens to be...

Personally, I don't think a straight line acceleration too much of a "race". When it comes to performance in dry tarmac, awd cars have managed very well. I remember awd Alfas winning touring car championships against rwd Mercedes and Audi. Those who think LSD is making a difference in apex exit speeds, think again. AWD is in a leaque of its own here.

When it comes to safety, statistics show that people will get killed in dry tarmac. Why? Because it allows high speeds and error/accident in high speed is lethal. Racing in a curvy snowy small road at 25-55mph is just fun, not dangerous.

Moreover, in less than perfect conditions, it's not just that awd is faster, but at a given speed awd is safer than rwd because of the better traction.

I have rwd e92, because its excellent. Were there the awd option already, I might have the perfect everyday performance xi (independent of weather conditions). Getting close to 400 bhp the everyday driving on average is more traction limited than power limited. And power can be added if needed; in addition to Procede; turbo back exhaust, intercooler, turbos, etc... But I cannot add too much traction [after having the tires of my choice]; 2 more wheel driving, in any other way than getting xi.

This is just a view to look at this, not disagreeing about what have been said in the thread. Btw, as far as I know, at 180 km/h and beyond xi becomes rwd avoiding the drivetrain losses at high speeds. And finally, as been said here before the number of the perfect dry tarmac days depends..., although it seems that there has not been a perfect dry tarmac day anywhere yet to get a decent traction and quarter mile time for Proceded 335

[Driver72]

Originally Posted by T Bone

Hey Driver72, I think most people agree with what you posted. My question that I have not been able to find an answer for is how BMW X Drive works versus the Audi Quattro.

Does Xdrive sap power like Quattro at high speed? I was under the impression Xdrive can completely disengage the front wheels so there is no parasitic losses at high speed.

If this is the case, the only difference in performance between the RWD and XI would be the extra 220 pounds....at high speed, this is much less an issue for acceleration.

This could be true. IF XDrive fully disengages the front wheels under
when NOT needed, and ONLY engages WHEN the rear wheels slip, true the only acceleration loss would be due to the 220 weight.
However, there MAY still be some extra drivetrain loss, as the power might have to go through a clutch type apparatus that "sends" the power to the front when needed. The power may still have to go through it on it's way to the rear wheels first.
I don't know though.

Ideally, someday some manufacturer will release this type of AWD system.
Better yet, an AWD system with an electronic switch which will ALLOW the driver to completely send 100% of the power to the rear wheels and completely turn OFF the AWD system and turn it back on when needed or wanted.

This way you could launch the car in AWD mode and shift to 2nd gear, then hit a button to send 100% of the power to the rear wheels and keep going.
As you pointed out, only the weight penalty would affect acceleration.