First Z - 3.0si or M?

[barkster99]

Forgive the newbie questions. Did some searches, still have questions. Any help is appreciated.

Looking for the perfect 2006-08 3.0si roadster, <30K miles. Given what I'm after (18", manual, maybe M seats), it seems I'm finding as many Ms as SIs with not as much price difference as I might have expected.

I'm concerned about ride quality in the M. I believe it's sprung a little stiffer, is that right? This will be a daily driver (when there's no snow around!) and I'm not the 20 year old wanna-be race car drive I used to be.

Any and all input appreciated, re: ride quality or anything else. Thanks.

[Nhopkins1394]

The 3.0si is fast but the ///M is faster. Totally different motors.
I think you're right about the suspension.
The si is plenty stiff for my 50 year old butt.

If you want a manual trans. go test drive both. I've heard that you'll not regret buying the ///M.
I am surprised you are not finding much price differences. The ///M should be several thousand dollars more.
Good luck on your search.

[inTgr8r]

Many guys daily their M.
Test drive them; you will know in a heartbeat which one is right.

[ga41]

I daily drive my M and the roads here are atrocious. It's not as stiff as some people make it out to be, my mates Audi TT with 19 inch S5 wheels has an equally stiff, if not stiffer ride.

As Nhopkins1394 and inTgr8r said, if you can then test drive both. You'll still end up with the M though. :P

[Swashplate]

Test drive and make sure to take your time. I daily mine.

[ZStig]

u'll end up in the M eventually anyway

[Nikki]

Originally Posted by Roffle Waffle

u'll end up in the M eventually anyway

LOL yep 3.0si --> M convert here. The 3.0si was definitely a better daily driver, with lots of low end and plenty of fun without getting me in trouble. The M is a completely different animal. It is really hard to drive the speed limit in the M.

[dazed^]

Yeah, a testdrive is the only answer.

Before I bought mine I was a little apprehensive about the ride quality in the M after having read numerous reports of "kart-like" experiences on forums like these. Turned out the ride was perfectly fine once I tried for myself.

[Nikki]

I think the ride is actually better in the M. Sure, it is stiffer but because of this when you go over bumps and potholes the car doesn't jerk around like the 3.0si did, forcing you to hang onto the steering wheel for dear life and and make subtle steering adjustments keep it under control. The M holds its ground well.

[Huz-Z]

I've got a 3.0si. When I got mine, there was quite a price difference between it and the M.

If you get a 3.0si, its no slouch, as will be apparent after you read this review:

http://www.auto123.com/en/bmw/z4/200...00&artid=90628

If low end performance is important, then a 3.0si may be a good choice. These cars came with stock run flat tires. Many here, including me, have replaced them with non run flats, similar to what the M cars have. That makes a massive improvement in the car's comfort and steering quality. The run flats simply suck!

Now, if the price difference between a 3.0si and an M is not significant for you, then you really should drive both cars and buy the one you like the best.

I'm not disappointed with my 3.0si at all. But I have yet to hear of a disappointed M owner either.

Good luck!!!

[Huz-Z]

Originally Posted by Nikki

I think the ride is actually better in the M. Sure, it is stiffer but because of this when you go over bumps and potholes the car doesn't jerk around like the 3.0si did, forcing you to hang onto the steering wheel for dear life and and make subtle steering adjustments keep it under control. The M holds its ground well.

For me, alll that went away when I replaced the stock run flat tires with Hankook V12's.

[Nikki]

Originally Posted by Huz-Z

For me, alll that went away when I replaced the stock run flat tires with Hankook V12's.

Yeah this was the suspension, not the tires. I'm talking about the really sh*t roads here in LA. Basically you hit certain parts on the roads and even if you're going like 25mph the car fights side to side and dances around because the pavement is so beat up. There's a lot of roads like that around LA.

like this, pretty much everywhere!

[Huz-Z]

Originally Posted by Nikki

Yeah this was the suspension, not the tires. I'm talking about the really sh*t roads here in LA. Basically you hit certain parts on the roads and even if you're going like 25mph the car fights side to side and dances around because the pavement is so beat up. There's a lot of roads like that around LA.

like this, pretty much everywhere!

Yipes - that IS severely bad roads! I though the roads here in St. John's Canada on the east coast were bad. The worst I have encountered is sudden cuts, breaks and potholes in the pavement that threaten to break a rim.

But I think that would be a concern for both the Z4M and the Z4 3.0si.

[Nikki]

Originally Posted by Huz-Z

Yipes - that IS severely bad roads! I though the roads here in St. John's Canada on the east coast were bad. The worst I have encountered is sudden cuts, breaks and potholes in the pavement that threaten to break a rim.

But I think that would be a concern for both the Z4M and the Z4 3.0si.

Yeah, it isn't good for either but the M handles it much more controlled because of the firm suspension. It is harsh but it goes straight over it without having to fight it.

[PatJags156]

I test drove both back to back. I ended up with the 3.0si. I felt as if it was much better as a daily driver, the M had so much power, it was hard to relax while driving it. 3.0si= Better gas mileage, lower insurance...and a few other reasons.

[Huz-Z]

Originally Posted by Nikki

Yeah, it isn't good for either but the M handles it much more controlled because of the firm suspension. It is harsh but it goes straight over it without having to fight it.

I don't doubt you, but since tossing the run flats, my car hasn't done that either, and I would wager that St. John's has some of the crappiest streets in North America.

One of life's little mysteries, I guess!

[GomboRombo]

I have an Si and love it, but if I could have pulled off the price difference I would have gotten an M.
If you can afford it, go for the M.

M owners correct me if I'm wrong, but doesn't the M require a valve adjustment every 20k or so? I hear it cost around $2k each time?

[Nikki]

Originally Posted by Huz-Z

I don't doubt you, but since tossing the run flats, my car hasn't done that either, and I would wager that St. John's has some of the crappiest streets in North America.

One of life's little mysteries, I guess!

Yeah I had non-runflats on my 3.0si but they were still Bridgestones. I did notice that they tramlined a bit more than the Michelins and Contis I've had on my M.

[Huz-Z]

Originally Posted by Nikki

Yeah I had non-runflats on my 3.0si but they were still Bridgestones. I did notice that they tramlined a bit more than the Michelins and Contis I've had on my M.

LIGHT BULB!!

Maybe its the particular non run flat tire! I am running Hankook V12's. Per another current thread here, that tire has a soft side wall. Perhaps that allows the V12 tire to absorb the road irregularities that were causing your previous 3.0 si to exhibit that twitchy behavior.

[pokeybritches]

The maintenance will be far more in the M with its valve adjustments and more expensive brakes. Gas mileage will be about 30-40% better in the 3.0si. The shifting in the 3.0si is smoother, and the engine revs buttery smooth.

However, there is little aftermarket support for the 3.0si. So, what you buy off of the dealer's lot is pretty much what you will have to live with. There is one supercharger kit under development, and it's expected to run very mild boost (3 PSI for stage 1, 6 PSI for stage 2 with water/meth injection). Its cast crank won't handle the power levels of the M54 (pre-2006 models) or S54 (M).

You can also check out the 3.0i (2006+) to 3.0si conversion. You won't have the uprated brakes or suspension, but you can achieve a big power gain over the standard 3.0i for just a few hundred dollars in parts and a tune.

If you ever plan on tracking the car, go for the M. Good luck!

[tekmoe]

Originally Posted by GomboRombo

I have an Si and love it, but if I could have pulled off the price difference I would have gotten an M.
If you can afford it, go for the M.

M owners correct me if I'm wrong, but doesn't the M require a valve adjustment every 20k or so? I hear it cost around $2k each time?

I don't think it costs that much. I've still got at least 15k to go before I need to have that done. I'll be taking it to an indy. I would imagine just the valve adjustment by itself would run anywhere from $600 to $1000 depending on the shop. Someone correct me if I am wrong.

[SMTM]

I have owned both a 2006 Z4 si roadster and an 2006 Z4M. I first leased the Z4 si for two years and turned it in. After turning it in I realized that I had mad a mistake and missed the convertible. So then I started looking at used Z4 si, and much like you found the price to be very similar. So I tried the Z4M and fell in love. Here are my observations.

1. The stock Z4M rides better than the Z4si because the si has run flats, the Z4M does not. Of course, you don't have to replace the runflats with new runflats.

2. What has not been said here, is that the Z4M has hydraulic steering out of the E46 M3. The Z4 si has electric. The difference here is UNBELIEVABLE!!!

3. The Z4M has limited slip, the si does not.

4. the Z4M trunk has a pump kit on the right side, the si does not.

5. the Z4M uses about 20% more fuel. The 3.0 si is actually reasonably efficient.

6. The Z4M is an M car and the dealer LOVES to charge way more for service and repairs because it is an M.

That said, I would never, ever give up my Z4M now that I have driven, and owned both. I think that Z4M's will be collectors cars because there are so few made. Now is the time to get them because of all the lease turn ins. They went out of production in 2008, and this will be the last year of the 3 year lease turn ins.

Drive both.

Good luck with your decision.