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  #1  
Old 08-17-2003, 12:50 PM
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Post ZHP vs xiT

In reference to this thread.

On Saturday morning, Steve and I met up to swap cars for a little test drive. For those familiar with the area (as I know some of you are) we went up MacArthur Bl from Persimmon Tree Ln to Falls Rd, turned around and went back down MacArthur to the Parkway and took that to Glen Echo where we returned cars. For those that aren't familiar with the area, MacArthur is a two lane road that has some straight sections and some very twisty bits. Parts of it are level and parts are hilly. The section that we drove is reasonably smooth for the most part, but there are some parts that are in need of repaving. The worst of it, though, is far from the worst of what the DC area has to offer. The Parkway is a limited access road that is just below Interstate quality. It's currently in good shape throughout the portion that we drove.

So, the ZHP is quicker, but the difference is not earth shattering. It feels like much of the extra power is above 4k, so you still have to work the engine a bit to get there...just like with the 2.5l engine. The difference is that the reward for getting there in the ZHP is larger, but not that much larger.

WRT ride and handling, keep in mind that I am comparing the ZHP with the stock tires to an xiT with Falken Azenis Sports, which aren't exactly typical street tires. That said...

I could definitely feel that the ZHP was lighter than the xiT. It felt just a little more flickable with less momentum to overcome for a given speed. However, the steering felt a little number and a little more ponderous than that in the xiT. The staggered wheel/tire setup of the ZHP made it much more prone to understeer. Still, the ZHP has quite a bit of grip. In my normal street driving, the understeer would rarely be an issue...and the times that it would, it would probably be welcomed.

The ZHP felt soft in comparison to the xiT. It was smooth, steady and stable, but it felt like something was missing. Body motions felt like they were well controlled, but something was getting lost between the road surface and the seat of my pants. The xiT's ride is noticeably firmer with a tad more more harshness (which only feels like harshness in comparison to the ZHP). body roll was less than the xiT, but the difference was barely noticeable from the driver seat.

My bottom line impression is that the ZHP doesn't compare all that well against the xiT. It's marginally quicker, has an overdrive gear, has a better steering wheel and that's about it. If bought new today, comparing comparably equipped models, the ZHP would invoice ~$4,500 more and ticker for ~$4,900. The xiT has more utility value, AWD and a reduced tendency to understeer (through less rear grip) over the ZHP for about 10% less money.

Overall, I was quite underwhelmed with the ZHP. I don't think that it's worth the difference. In fact, based on this drive, I don't think that even a regular 330i (let alone a ZHP) is worth the price premium over the 325i (a much greater difference than the 325xiT to 330i ZHP). A bunch of times I've said that I would have bought a 330iT or 330xiT if it had been available here. Well, if I had, and then had a chance to do this with a 325xiT, I would be pissed. The extra power would be nice to have, but it just ain't worth the money.

I have no doubt that the ZHP would do better times in autocrossing (especially after figuring out a solution to the f'ed up wheel/tire size issues), but I'm not sure that it would do much better in B Stock than the xiT does in D Stock.
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  #2  
Old 08-17-2003, 01:27 PM
LarryN LarryN is offline
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Clyde, that's a well written editorial. I do have to ask though. The ZHP is about 2 seconds quicker to 60 than the 325xit. That didn't feel like a lot to you? Even the Falkens couldn't account for that much more torque and hp.

I just had to wonder, because a M3 is about ~1.5 seconds quicker to 60 than my car, and the feeling of accelleration is brutal in comparison to my car ...and I know not everyhting is straight line speed.
  #3  
Old 08-17-2003, 01:36 PM
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You'd lose at least half a second if the xiT could reach sixty in second.
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Old 08-17-2003, 01:56 PM
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Clyde, just buy the ZHP
  #5  
Old 08-17-2003, 02:22 PM
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Quote:
Originally Posted by LarryN
Clyde, that's a well written editorial. I do have to ask though. The ZHP is about 2 seconds quicker to 60 than the 325xit. That didn't feel like a lot to you? Even the Falkens couldn't account for that much more torque and hp.

I just had to wonder, because a M3 is about ~1.5 seconds quicker to 60 than my car, and the feeling of accelleration is brutal in comparison to my car ...and I know not everyhting is straight line speed.
IMO, 0-60 times are kind of meaningless, particularly in terms of a real world comparison. Even if I found them meaningful, I'd have to see measured results taken at the same time and place (preferably with the same driver using the same technique) from both cars. AFAIK, the only published 0-60 times for the xiT have not been measured, but supplied by BMW. Actually, I'd rather see a rolling start 5-50 mph comparison as it would eliminate differences in launch traction and prevent a situation where one car has to shift a second time to reach 60 and the other doesn't (not sure if the ZHP needs to shift to 3rd to reach 60, but I know that the xiT does).

All of that said, the power generation in both the ZHP and xiT is incredibly smooth and seamless. Neither engine produces neck snapping torque down low like a number of American V8s nor do they have high rev peakiness like the 4 banger in the S2000 or the instant-on of something like a 930's turbo. The ZHP does come on more above 4k than the xiT, though, but until reaching almost 6k, it doesn't really feel like it's making that much more power even if measurements show that it actually is. That may be a testament to the engine family and the broad, linear torque curve that it generates. Depending on your point of view, that could be either a good or bad thing.

In the "real world" driving I did yesterday, the difference in power was noticeable but mostly unremarkable. This was with rolling starts to mid way through second gear. 50-80 in fourth and fifth gears. Sudden short bursts of full throttle at all speeds in all gears. Etc. I expected a bit more.
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  #6  
Old 08-17-2003, 02:39 PM
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Quote:
Originally Posted by ·clyde·
In the "real world" driving I did yesterday, the difference in power was noticeable but mostly unremarkable. This was with rolling starts to mid way through second gear. 50-80 in fourth and fifth gears. Sudden short bursts of full throttle at all speeds in all gears. Etc. I expected a bit more.
Having come from a 323i to the 330i (both were similary equipt), I found the difference immediate, but not overwhelming at first. Once you have the car for a few weeks, and during normal driving you notice, "wow, I would have had to downshift to get that feeling in the 323", or "Crap, I realy didn't need to downshift there" (as you chirp-accelerate)...

I would imagine that the difference in the torque would be similar between the ZHP and xiT.

I can totally see your point about the wagon being stiffer. Hey, it's designed to haul things. I would expect a firmer ride. I often wonder that now I'm doing pretty good during autox'es (taking the lines I want to take), how I would do back in the 'ole 323i, since I was a greeen-as-they-get newbie when I was running that car.

Oh, Clyde, I can't think of anybody who would think that a broad linear torque curve would be a bad thing. Maybe I misunderstood that part.
  #7  
Old 08-17-2003, 03:30 PM
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Quote:
Originally Posted by ·clyde·
AFAIK, the only published 0-60 times for the xiT have not been measured, but supplied by BMW. Actually, I'd rather see a rolling start 5-50 mph comparison...
Car & Driver tested a 325xiT here...

http://www.caranddriver.com/article....&page_number=1

...but they don't include the instrumented test results on the web. I guess I could find this issue when I get home...
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  #8  
Old 08-17-2003, 03:38 PM
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Quote:
Originally Posted by LarryN
Having come from a 323i to the 330i (both were similary equipt), I found the difference immediate, but not overwhelming at first. Once you have the car for a few weeks, and during normal driving you notice, "wow, I would have had to downshift to get that feeling in the 323", or "Crap, I realy didn't need to downshift there" (as you chirp-accelerate)...
If you don't want to shift, get an auto tranny

Seriously, most of my driving history has been spent in high powered cars, most of them low end torque monsters. They didn't breathe well at high revs, but from low engine speeds they ALWAYS let you know what they were made to do with any more than a light touch of the throttle.

Quote:
I can totally see your point about the wagon being stiffer. Hey, it's designed to haul things. I would expect a firmer ride.
I do wonder how much is attributable to the tires.

Quote:
Oh, Clyde, I can't think of anybody who would think that a broad linear torque curve would be a bad thing. Maybe I misunderstood that part.
Think of me and you can think of one. Broad, linear torque curves are good, but they aren't much fun, IMO.
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  #9  
Old 08-17-2003, 03:47 PM
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Quote:
Originally Posted by PhilH
Car & Driver tested a 325xiT here...

http://www.caranddriver.com/article....&page_number=1

...but they don't include the instrumented test results on the web. I guess I could find this issue when I get home...
Wonder how I forgot that one. I remember reading that compro about a dozen times before I ordered my wagon. I missed it when I was looking through my collection. Thanks.

0-60 7.6 seconds for the 2001 model in that test.
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Old 08-17-2003, 06:15 PM
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Different people will have different perceptions.

I've got an '02 325i w/ sport pkg and 5 spd. Love it. Recently drove my 325 to a dealer to test drive an '03 330i ZHP and was highly impressed with the different character of the cars. The ZHP seemed to egg me on at all points in the rev range. The car felt much more responsive to throttle inputs and the sense of immediateness to the throttle was right now! I ran it up to about 6500 RPM several times and was almost giggling with the rush of power in the upper rev range -- and I love to play above 5000 RPM. The sound of the engine with the more open exhaust was delirious.

The suspension didn't seem any tighter than my 325 and the understeer was not as bad as I thought it would be. OTOH, the more tractable, more powerful engine makes the ZHP chassis easier to balance and set than my car.

Also, I like the alcantara steering wheel and the red needles on the instruments. The subtle body panel upgrades are awsome, yet tasteful. Small stuff but still distinctive.

Now I really want one
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  #11  
Old 08-17-2003, 11:03 PM
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agree

Quote:
Clyde:
Actually, I'd rather see a rolling start 5-50 mph comparison as it would eliminate differences in launch traction and prevent a situation where one car has to shift a second time to reach 60 and the other doesn't (not sure if the ZHP needs to shift to 3rd to reach 60, but I know that the xiT does).
I agree with you 100% on that. Maybe even 5-80 should be the norm. And 2nd gear reaches 60 in my ZHP without redlining.
  #12  
Old 08-18-2003, 09:23 AM
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Wow, respectfully, were your bodily senses dead that day or did you forget how to shift?

I have had a 325 before and there is NO doubt my current ZHP is SIGNIFICANTLY faster then the 325...you are talking 50 additional HP and ft/lbs of torque.

The biggest difference to me is really in the lower RPM's because the 325 is a dog until 4K where my ZHP is pretty good even in the 2-3K range.
  #13  
Old 08-18-2003, 09:56 AM
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Originally Posted by greginaz1
Wow, respectfully, were your bodily senses dead that day or did you forget how to shift?

I have had a 325 before and there is NO doubt my current ZHP is SIGNIFICANTLY faster then the 325...you are talking 50 additional HP and ft/lbs of torque.

The biggest difference to me is really in the lower RPM's because the 325 is a dog until 4K where my ZHP is pretty good even in the 2-3K range.
I don't doubt that measurements would show the ZHP to be significantly quicker. It just didn't feel like it was that much quicker.
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Old 08-18-2003, 10:55 AM
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Quote:
Originally Posted by ·clyde·
I don't doubt that measurements would show the ZHP to be significantly quicker. It just didn't feel like it was that much quicker.

With a lot of these comparisons, we're the victim of our own expectations. I know when I first drove the E46 M3, I thought to myself (and posted here) "what's the big deal?" In reality, I had set myself up for a quantum leap in terms of performance and feel, and the E46 M3 just didn't deliver.

I suspect it is the same with the ZHP. The ZHP *is* substantially faster than the XiT--if you believe magazine numbers, it's about 2 seconds quicker to 60 (5.6 v. 7.6), which is a substantial difference even if 0-60 as a metric has flaws. Moreover, with 235 hp, more torque, and taller gearing, the 330 is just going to walk away from the XiT once the speeds get into the high double and triple digits. That said, they're both E46s. They both use the same basic engine block, and similar suspension geometry. They'll both feel (broadly) similar. The ZHP is the XiT only more so, but in the end it will feel essentially the same.

And so, incidentally, will the M3, which feels for all the world like my old 323 with a stiff suspension and a really, really big engine.
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Old 08-18-2003, 11:27 AM
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Originally Posted by JST
With a lot of these comparisons, we're the victim of our own expectations. I know when I first drove the E46 M3, I thought to myself (and posted here) "what's the big deal?" In reality, I had set myself up for a quantum leap in terms of performance and feel, and the E46 M3 just didn't deliver.

I suspect it is the same with the ZHP. The ZHP *is* substantially faster than the XiT--if you believe magazine numbers, it's about 2 seconds quicker to 60 (5.6 v. 7.6), which is a substantial difference even if 0-60 as a metric has flaws. Moreover, with 235 hp, more torque, and taller gearing, the 330 is just going to walk away from the XiT once the speeds get into the high double and triple digits. That said, they're both E46s. They both use the same basic engine block, and similar suspension geometry. They'll both feel (broadly) similar. The ZHP is the XiT only more so, but in the end it will feel essentially the same.

And so, incidentally, will the M3, which feels for all the world like my old 323 with a stiff suspension and a really, really big engine.
I think that you're right on for the most part. When Phil was contemplating dumping his xiT for the ZHP he wound up buying, that's essentially what I was telling him. That situation was different as he was trading in and buying new (and thus spending a lot more for the "upgrade" than I would be if Steve and I were to swap) and his xiT was a slushie to begin with.

Before driving Steve's car, I thought that my expectations concerning power were reasonable, although I was hoping that they would be exceeded. In reality, though, my expectations weren't even met. I'm more than happy to concede that my expecations may have been unreasonable, but I really don't think that they were.

The bigger let down for me, though, was in ride and handling. As we all know, the xiT does not have a real "sport" suspension. To be fair, the xiT is supposed to have a firmer suspension than the base 325iT. However, it is not supposed to be as stiff as the 325iT with the sport suspension. The 330i is supposed to come standard with a sport suspension (and whether the ZHP actually adds to that appears to be a hotly debated topic these days). What I found was a ride in the ZHP that was noticeably softer than in my xiT. Of course, the caveat is that I have the Azenis on the xiT. I am sure that accounts for some of the difference, but I doubt that they are wholly responsible for it (but I'd welcome the chance, if given the opportunity, to prove myself wrong by mounting them on the ZHP).
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Old 08-18-2003, 11:34 AM
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Quote:
Originally Posted by ·clyde·
I think that you're right on for the most part. When Phil was contemplating dumping his xiT for the ZHP he wound up buying, that's essentially what I was telling him. That situation was different as he was trading in and buying new (and thus spending a lot more for the "upgrade" than I would be if Steve and I were to swap) and his xiT was a slushie to begin with.

Before driving Steve's car, I thought that my expectations concerning power were reasonable, although I was hoping that they would be exceeded. In reality, though, my expectations weren't even met. I'm more than happy to concede that my expecations may have been unreasonable, but I really don't think that they were.

The bigger let down for me, though, was in ride and handling. As we all know, the xiT does not have a real "sport" suspension. To be fair, the xiT is supposed to have a firmer suspension than the base 325iT. However, it is not supposed to be as stiff as the 325iT with the sport suspension. The 330i is supposed to come standard with a sport suspension (and whether the ZHP actually adds to that appears to be a hotly debated topic these days). What I found was a ride in the ZHP that was noticeably softer than in my xiT. Of course, the caveat is that I have the Azenis on the xiT. I am sure that accounts for some of the difference, but I doubt that they are wholly responsible for it (but I'd welcome the chance, if given the opportunity, to prove myself wrong by mounting them on the ZHP).
Softer in what manner? Was it the damping that was softer? The rebound damping, or the initial jounce damping? Springs? Roll bars? All of the above?

Tires are obviously a big contributing factor, though IIRC Steve's car has Pilot Sports, and in the 18" size (your Azenis are 17s, aren't they?) there shouldn't be a whole lot of sidewall flex.

I've noticed that the M3 is "softer" than my old Koni'd E36 in some ways, though in others it's much firmer. It has a lot better initial absorbtion of bumps than the E36 did; it doesn't crash the way that the (I think slightly overdamped) E36 could. OTOH, it has very, very little body roll.
  #17  
Old 08-18-2003, 12:30 PM
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First, Both cars are fantastic and suit each of us individual owners very well. Obviuosly you chose your car and mods carefully for you, and you have chosen wisely, for you.
Quote:
Originally Posted by ·clyde·
I don't doubt that measurements would show the ZHP to be significantly quicker. It just didn't feel like it was that much quicker.
Clyde your car has significantly shorter overall drive ratio, doesn't it? I would bet at sub-interstate/non-Stuka speeds, that would be a great equalizer. Although, I do get 22-25 mpg with the 6 spd and tallish final, while still having good ratios in 2nd and 3rd for fun.
Also, as far as understeer, I tried one of the easy solutions, and went to 38psi all around (vs. 32f-38r) and that really sharpened turn-in, signifcantly improved balance, and ride actually improved slightly. Was your comparo car adjusted, or near stock?
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Old 08-18-2003, 12:37 PM
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Quote:
Originally Posted by JST
Softer in what manner? Was it the damping that was softer? The rebound damping, or the initial jounce damping? Springs? Roll bars? All of the above?

Tires are obviously a big contributing factor, though IIRC Steve's car has Pilot Sports, and in the 18" size (your Azenis are 17s, aren't they?) there shouldn't be a whole lot of sidewall flex.

I've noticed that the M3 is "softer" than my old Koni'd E36 in some ways, though in others it's much firmer. It has a lot better initial absorbtion of bumps than the E36 did; it doesn't crash the way that the (I think slightly overdamped) E36 could. OTOH, it has very, very little body roll.
Both initial and rebound felt softer, giving a more subdued sensation. There was more shifting between adjacent corners in turns while passing over undulations in the surface (which makes me think springs, ). Body roll was less than in the xiT.

You're correct about tires and sizes on the two cars, but the sidewall flex is only part of it. Per square inch of contact patch, the Azenis have a lot more rubber touching the ground than the Pilots which lets them pick up and transmit a lot more towards the seat of the pants.

Equipped as they are, the ZHP was definitely more Buick like than the xiT.
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Old 08-18-2003, 12:51 PM
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One thing I noticed on the track riding in my Instructor's 325Ci SP (his first time on the track in that car, too) was that it had some pretty scary body roll at the limit. The xiT corners on the bump stops so far as I can tell, which must have something of an effect on its ride. (Take a look at how little space there is between the bump stops and the strut if you don't believe me.)

I really wish I was withing six hours drive of Ground Control... I'd drag my ass over there and have them take a gander at my suspension.
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  #20  
Old 08-18-2003, 01:02 PM
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Quote:
Originally Posted by wrwicky
Clyde your car has significantly shorter overall drive ratio, doesn't it? I would bet at sub-interstate/non-Stuka speeds, that would be a great equalizer. Although, I do get 22-25 mpg with the 6 spd and tallish final, while still having good ratios in 2nd and 3rd for fun.
The ZHP has a final of 3.07 and the xiT 3.23. Also, the ZHP's first gear is slightly shorter (if the specs from bmwusa.com are correct) at 4.35 compared to 4.21. 2nd, 3rd and 4th are all nearly identical.

Quote:
Also, as far as understeer, I tried one of the easy solutions, and went to 38psi all around (vs. 32f-38r) and that really sharpened turn-in, signifcantly improved balance, and ride actually improved slightly. Was your comparo car adjusted, or near stock?
I'm not sure where Steve had his pressures set, but the staggered tire size builds in a LOT of excess understeer compared to the xiT. Running 42-43 up front with 36-37 in back in the same sized Azenis makes the xiT just a bit tail happy on turn in when autocrossing. To get that kind of balance out of the ZHP with the 225 fronts and 255 rears, you'd have to reduce pressure so far that you would be overly susceptible to power oversteer on corner exit. It would only be a problem for me while autocrossing. While it's not a difficult problem to fix, it becomes more difficult (or at least more expensive than it should be) to fix and stay B Stock legal for SCCA events (and those using their classing rules) because of BMW's wheel size choice.
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Old 08-18-2003, 02:33 PM
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Quote:
Originally Posted by ·clyde·
To get that kind of balance out of the ZHP with the 225 fronts and 255 rears, you'd have to reduce pressure so far that you would be overly susceptible to power oversteer on corner exit. It would only be a problem for me while autocrossing. While it's not a difficult problem to fix, it becomes more difficult (or at least more expensive than it should be) to fix and stay B Stock legal for SCCA events (and those using their classing rules) because of BMW's wheel size choice.
I have never autocrossed in my life. I did however take my ZHP to Summit Point and compared it there with my previous E36 M3. Based on this admittedly one-sided track experience, I would not recommend the ZHP for auto-x, only for open track runs, because of the relatively "narrow" power band.

The only time the ZHP really came alive at the track was in the VERY upper ranges of the RPM band, above 5k initially and most noticeably above 6k rpm. When coming out of corners, the 2000 M Coupe in front of me would pull away initially and I could only watch this in frustration. Then at some point on the straights I would start to reel it in and completely catch up to it towards redline in 3rd. (BTW redline in 3rd is around 95mph and in 2nd gets you to 65mph or so.) The only performance mod that I would currenly consider would be a LSD with shorter gearing (3:23 maybe?).

So I came to the conclusion that redline makes or brakes performance in the ZHP car. I'm not that surprised the difference wasn't extreme in "daily" driving conditions.

And yes, the "circuit" you used was exactly what I used to finish initial break-in for my car and get it ready for the track . It was the only place close to home where I could redline in 2nd the 3rd.

adc
03 330 ZHP
 

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