(Newbie Z3-coupé thread) Differences between M models and non-M?

[BenFenner]

I'll make this short so people will actually read it. I tend to write books for posts.

I'm not new to cars, performance, or even BMW. I am however new to the Z3-coupe and M-coupe scene. I've lusted after a coupe (no offense to the roaster guys!) since I first saw one over 10 years ago. It is the best looking car ever made in my opinion. I doesn't hurt that it's also an incredibly fun car to drive as well. I'm finally in the position where it makes sense to start seriously considering buying one. I could pay cash right now for an '01-'02 coupe but I think my plan is to pick up a 3.0L model and then sell it in a few years and trade up to the M version (because the difference should go towards the house instead). With that in mind, I have quite a few questions as to the differences between the lesser models and the S54 M coupe. (I'm not considering an S52 car right now but maybe I could be convinced if you think that's the right way to go.)

I'd be keeping the Z3-coupe mostly stock to retain it's resale value (and personally I don't think it needs much modification for me to enjoy the hell out of it--I have test driven one and have many hours in a 2.8L roadster) but I'm wondering what the differences are between the lesser models and the M versions. Basically I want to know what I'm getting into, and what performance parts (if any) will translate over to the M version with respect to suspension, wheels, etc. (I know the engine stuff is going to be completely different.)

I assume the sub-frame issue is for all models?
I assume the Ms are the only ones that got an LSD?
Same goes for larger brakes?

I know the Ms got roadstars, the front fascia with the winglets, and the quad pipes and accommodating bumper.

Are the fenders any wider in the back or front?
Was there a face-lift between 1999 and 2002 I don't know about other than the engine changes?
I hear the rear end is narrower on the Ms from brake rotor to brake rotor. Is that true? (I'm wondering about wheel offset here.)
Are the rear suspension pick-up points different on the chassis side? (Or can an entire M rear be swapped into the non-M model?)


I'm basically hoping that with a few directed questions and enthusiasm I'll get some helpful answers. I'm a helpful/contributing member of many other car forums so please know that I've searched on this forum for a while and I'm not asking for handouts. Simple, quick answers are fine. Tell me to search for a specific topic if that is appropriate.

Thanks in advance.

[JoshS]

Try this: http://www.mcoupebuyersguide.com/ind...e-non-m-coupe/

They have absolutely the same unibody, so are subject to the same "subframe" issue.

They all have LSD, although the '99+ non-M has a Torsen-style, not a clutch-pack.

Yes, the M has larger brakes, vented in the rear too.

Identical fenders. But the trailing arms are different, so the M's whole rear suspension is narrower than the non-M -- hence they use a rear wheel with a very low offset to move the wheel outboard. In my opinion there's no practical advantage to the M's rear suspension over the non-M, and the funky offsets make it much harder to find wheels. The non-M can use any E36/E46/E90 wheel at all four corners. All z3s can all fit the same diameters, widths, and tire sizes (and you can go very wide in the rear, M or not).

No facelift on the Coupes, although there were subtle differences in chrome bits through the years.

[BenFenner]

That's the exact info I'm looking for Josh. Thanks for the quick reply and succinct answers. That helps me a ton!

If I have any other questions on the differences I'll post them but for now I think you hit on all the pertinent points for me.

Thanks for the link too. It's exactly what I needed.

[dougmcintyre]

I wouldn't eliminate the S52 coupe. Be open to all possibilities. Look for the best condition coupe, M or non-M, you can afford to buy.

[Jeremy]

Welcome to the forum. Good luck with the hunt.

I'm on my third Coupe now. My first was a 99 Montreal Blue Z3 Coupe, second was a 99 Artic Silver M Coupe, and now I have what I really wanted all along, 02 LSB M Coupe. I've bought them all well, and sold them right around what I paid for them in basically the same condition, if not improved, with a few more miles. Start with whatever is affordable and accessible. Move up as budget allows, and you decide exactly what you want in the long run.

[lokijibber]

If you're ultimately after an S54 Coupe, buy one now. It's only a matter of time before the prices flatten out or even go up, the roadsters are already dropping much faster.

Price of an S52 may not be that more than a 3.0, but ownership cost will obviously be higher.

[BMWBergy]

Ben,

My only thought is this: Go straight for the M.

My reasoning is this: You want an S54 M, which are, at present, 8- or 9-year-old cars. If you get a non-M now, and keep it for 3 years, then move to an M (11- and 12-year-old cars at that point), your search for the right M will be even harder than it is now. While we have a good number of the 2000-ish ('99-'02) M owners on here, we don't have all of them; and while the folks we do have here are *generally* good to their cars, some of them are not - I'd hazard a guess that the same (i.e. that some are good, some are not) can be said of those M owners that are not part of this board. The longer you wait, the bigger your gamble.

Before you buy, search for M models as well as non-. Be patient, be picky. If you find a non-M that is too good to pass up, and you are not finding comparable M versions, well, you may end up pulling the trigger on the non-M, and you can't be blamed for that. But if you are finding that the Ms are not meeting your expectations for aesthetic or mechanical reasons at this point, imagine how much more difficult the search might be in three years.

Price of an S52 may not be that more than a 3.0, but ownership cost will obviously be higher.

I don't know that this is totally true. Cost of replacement of the motor in the event of a catastrophic failure will definitely be higher, but fluids, brake pads, and other routine consumables are not that much more expensive.

[BenFenner]

Doug I'll take your advice into consideration. The only reason it's not in the cards is because of the price. Maybe too expensive for now, but later I could likely afford the S54. Your comment on the condition makes tons of sense. I will look for good condition for sure regardless.

Thanks for the welcome Z3Couper. I've been biding my time, messing around with other cars until the chance to own this dream car has come up. Now might be the time (however it might not work out for maybe a year or so if it does). I like to plan way ahead and since I've been digging into this heavily it made sense to have some questions answered before I make serious and major decisions.

Since I'm new here, and will likely be here in some capacity eventually no matter what, I'll help you guys out with a view of my recent past with cars.

A buddy of mine and I put together this 475WHP e30: http://www.e30tech.com/forum/showthr...t=danmartin%27

And my current car right now is a 300WHP SE-R: http://www.sr20-forum.com/members-ri....html#post6034

There's been other cars in and out but those are the most well documented. I have a thing for sleepers.

[Z3speed4me]

If you are worrying about resale value... mod's if done properly and are welcomed items, will not hurt your price, but it won't help it much either.


At this moment in time, depending on what you budget is, go straight for an s54 if you want to keep it stock, check the subframe, go over the bushings and everything, check out the cooling system, have the rod bearings done, and call it a day.

If you really want to mod, well then you just kinda have to buy an s52 and go FI. S54's have plenty of aftermarket stuff, but the market is different and more costly.


As far as cost, ok well I had my subframe reinforced, that can be needed (or not) for any MZ3 car, did the cooling over (basically necessary), redid suspension after 60k miles of stock driving (probably also a thought to put in your head), did brakes over, and well that's it. Everything else is fun parts.... and half of those parts above make the car more fun anyway.

Maintaining these cars are no different from anything else, take care of her and she will do the same for you.

Either way, I'd look for a coupe from a forum member, almost but not guaranteed, to be taken care of pretty well. At least better than from elsewhere like randomly on autotrader.

[BenFenner]

lokijibber and BMWBergy, I'm wavering back and forth a bit right now. There are a lot of things I like about the M, but there are drawbacks as well for me. If I were to get an M I would be swapping out the front fascia for one without the winglets. I like the fact that the non-M can run the same wheels all around versus the stagger needed for the M. I also can't stand the roadstar wheels (sorry guys!) and much prefer the high spoke count and look of the non-M wheels I've seen. I'd likely be upgrading the suspension on the M anyway, so some of the expenses going into the future M could be done to the non-M to get it to where I want it to be. (Maybe I'd be happy with a non-M forever?)

I like the license plate on the hatch on the M for sure, and the rear bumper looks way better. I'm not entirely concerned about the engines to be honest or the power. I can take care of that if I have to. I've driven a 3.0L and while obviously I'd like more power. For me right now it's totally adequate.

I actually am maybe considering a non-M and just upgrading it here and there (brakes and suspension) up to the level of an M minus the power. If I want the power, I know the M54 could certainly get me there with a little convincing...

Can you two make a case for the M in light of all that?



Ken, thanks for replying. I see you're very helpful in all the threads I've read.
The eventual goal for the M version would be to stay away from the engine mods if I can but certainly go all out on the other areas that can be helped, mostly suspension/chassis mods.

The reason I'd be keeping the non-M mostly stock would be to keep resale value high and save for the M. (And put things on it that would transfer over directly to the M if possible.)

If you really want to mod, well then you just kinda have to buy an s52 and go FI. S54's have plenty of aftermarket stuff, but the market is different and more costly.

What if I can TIG weld my own turbo manifold and aluminum bits, have extensive experience with stand-alone tuning, and similar? Does that make the S54 just as inexpensive to work with?
(I know the M3 guys have absolutely no room for a turbo manifold in their engine bay with the S54. Same for these cars?)

[BMWBergy]

Can you two make a case for the M in light of all that?

Not really, no - at least not when you put all that context into your argument. I was honestly providing my input based on the specific statement you made in your original post:

I could pay cash right now for an '01-'02 coupé but I think my plan is to pick up a 3.0L model and then sell it in a few years and trade up to the M version (because the difference should go towards the house instead).

From that sentence, I inferred (nah, you implied ) that you'd be in an M eventually. As such, I wasn't trying to make an overall argument for an M over a non-M, I was merely trying to say: if you are eventually going to be in an M, skip the non-M entirely. However, your last post leads me to believe that you haven't really come to a conclusion, and are still on the M/non-M fence.

Considering that, I'll say this: I loved my E36 328i, and viewed it in a totally different, more civilized light than the 99 M3 and 2x 00 M Coupes I've owned since. It felt more tame, but I could still wring it out on the track. I disliked, however, its lack of an LSD. That is where a prospective Z3 coupe owner can feel happy - as already pointed out, all of them came with LSDs. In addition, the Z3s have broader interior and exterior color palettes available (including a more distinct and attractive brown-toned interior - that luscious 'camel' or 'caramel' color - if you go for brown/tan interiors, that is), and as you pointed out, greater flexibility with wheels.

How many Z3 and MZ3 Coupes have you driven? I think your own comfort with (and within) the vehicle should be one of your main criteria.

[BenFenner]

From that sentence, I inferred (nah, you implied ) that you'd be in an M eventually.

Oh of course. I've just been slightly swayed by some of the info I've uncovered in the last couple hours since making the first post. =D

So I may in fact be on the fence completely now. =]

I was just thinking out loud and like you said, trying to give more context.

How many Z3 and MZ3 Coupes have you driven? I think your own comfort with (and within) the vehicle should be one of your main criteria.

I've driven a 2.8L Z3 roadster that my aunt owned (and I helped her pick out). It easily won out over an [automatic] 350Z convertible, [automatic] RX8, Mazdaspeed turbo miata, Mini Cooper S, Porsche Boxster, Toyota MR2-S, VW Golf R32 and Honda S2000. I've been able to put it through it's paces and I was quite happy with it inside and out. I actually loved the soft top too. However I will give that up for the looks and rigidity of the coupe.

I've driven a 3.0L coupe on a test drive. If felt exactly like the 2.8L roadster except it was like being in a pillbox. Not my favorite thing in the world (I love an open cabin to see out of) but again, something I would sacrifice to see that coupe in my garage/driveway every day.

That's about it. I'm familiar enough with BMW now to know they have a good enough shift linkage feel for me. Good enough pedal placement, great seating position, etc.
I'm fine with all that. Very much comfortable. Things could be better obviously, but I'm very picky in that department and "good enough" is high praise I promise you. Frankly this is the only OEM vehicle below $50k I see myself actually happy enough with to own (save for my current car).

I would love to have more miles under my belt in one, or have driven more of them but that just hasn't been in the cards for me.

[Z3speed4me]

If you can make nice turbo manifolds, and somehow tune perfectly for the s54 but haven't yet, you should be worrying about making A LOT of money and not buying a cheap m coupe.

[BenFenner]

You're saying no one can tune the S54 properly on boost?
I'm not exactly sure how to take your post. I can make a great turbo manifold, yes. I also have had good success tuning fuel and ignition (and idle, and cold start, and xyz) for various engines; BMWs included. I like to think I'm good at it. I just don't want to go into business doing that sort of thing, if you know what I mean?

Okay I take that back. I've been "flown out and put up" at places to tune BMWs and paid for it. I don't mind that. ;-)
I don't need to make welding manifolds my business. Tuning the occasional engine is fine with me provided all I have to deal with is a laptop (no wrenching/wiring). That's not a common request however I feel.

[Z3speed4me]

Sorry just saying I never heard of you and I would think this stuff about the coupes and which motor to go with would be knowledge you have already attained if you are out tuning bmws (especially s54s) around the country thats all...

Not many folks I know that do boost work on that motor and tuners kinda make themselves known most of the time if you have skills like that.

[BenFenner]

No, you wouldn't have heard of me. I've kept to other scenes so far and I'm really small peanuts compared to many others. I didn't mean for you to get the wrong idea about me. I haven't ever touched an S54. I've mainly only had the chance to work with M20s actually (as far as BMW engines go). Managed to get 475WHP out of an M20B25 without too much effort (stock internals, stock head gasket, stock cams, pump gas only, etc.) and have had success tuning other M20 variants. 12 valves is not a lot to work with. I can only imagine having 24 at my disposal. =D

I've always heard the S54 was good for 600 WHP bone stock, and that 1,000+ with internals was no big deal. That's what I was lead to believe anyway, and it makes sense. And obviously someone had to tune those engines.

Don't get me wrong. The coupe is supposed to be my sane daily driver, so I don't have those sort of aspirations for it (I would love to keep the engine N/A and completely stock). I'm just letting you know where I'm coming from.

[Jeremy]

I've always heard the S54 was good for 600 WHP bone stock, and that 1,000+ with internals was no big deal. That's what I was lead to believe anyway, and it makes sense. And obviously someone had to tune those engines.

Uhhhh...where do I send a payment?

[BenFenner]

I mean, the F20C (2 liter Honda S2000 engine) is good for 600-700 WHP completely unopened (although most opt for a thicker head gasket, don't get me started).
The S54 is a stout engine (from what I've heard, seen, and read). This sounds like news to you guys though? Maybe I've been severely mislead?

However, I guess at the end of the day for me that doesn't exactly matter since I'm not planning to do anything like that with this one. If there's a thread about the power handling ability of the S54 then that's where I'll head for more information and discussion on that topic. I'd hate for us to get side tracked here unless others feel it appropriate.

[Nijapo]

I've got a 3.0 coupe and I really wish I had waited until I found a nice S52 M. From what I've been reading the S52 is a nice platform that responds well to modification and has a powerband that is optimal for daily driving.

The M54B30 (3.0 Motor) does have issues. There have been several threads about the issues of engine harmonics, dropping oil squirters, and even the infamous oil pump nut issue. We've also got to keep an eye out for bad Vanos Seals, broken vacuum lines around the CCV/oil separator, bad DISA valves and faulty waterpumps.

So with this is mind, the S52 is a more reliable powerplant and responds better to modification.

[BenFenner]

The engine info about the M54B30 is excellent for me. Really helps me make choices and search threads for full explanations. Thank you.

[z3papa]

I've got a 3.0 coupe and I really wish I had waited until I found a nice S52 M. From what I've been reading the S52 is a nice platform that responds well to modification and has a powerband that is optimal for daily driving.

The M54B30 (3.0 Motor) does have issues. There have been several threads about the issues of engine harmonics, dropping oil squirters, and even the infamous oil pump nut issue. We've also got to keep an eye out for bad Vanos Seals, broken vacuum lines around the CCV/oil separator, bad DISA valves and faulty waterpumps.

So with this is mind, the S52 is a more reliable powerplant and responds better to modification.

I guess I have got to disagree about the reliability of the 3.0. It seems pretty bullet proof even with pretty aggressive use. All units need a little attention and giving attention does not mean the engine is without merits.

[Iceman00]

For a stock engine, the M54 is no more unreliable than a S52, and should perform fairly similar. I do agree though, cooling systems (bane of ANY BMW), could make or break the aluminum block. The oil pump is generally only an issue if you keep the car in higher rpm. Otherwise Vanos can go bad on both single and dual vanos engines(though not as serious as it sounds) DISA valves rarely go bad, and water pumps and vacuum lines are wear items on BOTH motors that should be replaced regardless.

[JoshS]

The M54B30 (3.0 Motor) does have issues. There have been several threads about the issues of engine harmonics, dropping oil squirters, and even the infamous oil pump nut issue. We've also got to keep an eye out for bad Vanos Seals, broken vacuum lines around the CCV/oil separator, bad DISA valves and faulty waterpumps.

Dude, *all* of the engines that came in Z3s have the oil pump issue, vanos seal issues, vacuum line issues, and faulty water pumps!

I haven't heard about those other ones.

[BenFenner]

I kind of assumed the water pumps were all a bit questionable based on what I'd heard. Plastic impellers right? Silly Germans...

The oil pump is generally only an issue if you keep the car in higher rpm.

High rpm operation is on the menu for sure.

[JoshS]

I kind of assumed the water pumps were all a bit questionable based on what I'd heard. Plastic impellers right? Silly Germans...

High rpm operation is on the menu for sure.

Easy to prevent. The issue is that the nut holding the chain sprocket onto the shaft backs off (and you can imagine what happens after that.) To prevent, just wire the nut or tack weld it to the shaft.