Brand Old Z3

[dshinR]

First post, new to this kind of stuff so take it easy gents.

Just got a 97 Z3 that had 70k miles on it.
It's got a little cosmetic problems like side mirror is hanging by tape, the place where u have your arm to flip up the soft top is broken, the driver seat doesn't move.

Either way, I am looking to drive this a couple years and have a little fun with it.

I did start reading at the different builds on the turbo section and I am looking at Garrett and CXRacing for some turbo kits for the near future.

I have about $2000 right now to have fun.

Recommendations? or even a path to a fun build?

Thanks for having me!

O, the card counter seems like he knows what he's doing. anyone know what type of builds he's done?

[cyberman]

I'm new here too, with a 96 Z3 that has the 4-cylinder 1.9 L engine. First thing I learned was to specify your engine. If the 4 cylinder, it's the M44. There are 6-cylinder versions and it makes a difference. The second thing I learned was that the first thing you HAVE TO DO. Is replace the cooling system, primarily the two plastic fittings - one is a straight pipe on the side of the block under the intake manifold and the other is bolted behind the block, a Y-connector. To get to these bits is a major job, pelican parts has a step-by-step procedure. The reason you have to do this is because with age, they get brittle, break and then the engine overheats quickly and you're in for costly repairs. Don't blow this off, that's the message I've gotten repeatedly.

[dshinR]

Thanks for the reply Cyberman, my 97 Z3 is the 6 cylinder 2.8L M52B28. Since I am looking into turbo kits, would replacing the cooling system with the intercooler work? Since I dont know what to look for, do you have any pictures to help me understand which pelican part would fix this problem.

Thanks!

[cyberman]

I don't know about the 6-cylinder with an intercooler, maybe someone else can clarify. But for a basic, step-by-step rundown of cooling system replacement for both the 4 and 6, you can't beat Pelican Parts which has the steps and pictures to go along with it. See: https://www.pelicanparts.com/BMW/tec...eplacement.htm

and you'll have to also refer to their separate guides on (depends on your experience):

Intake manifold (the hard part): https://www.pelicanparts.com/BMW/tec...eplacement.htm

Thermostat housing and thermostat: https://www.pelicanparts.com/BMW/tec...eplacement.htm

Most of us just do the whole thing, all rubber hoses and there are many, vacuum hoses, water pump, fan blades, belts, tensioners and pulleys. If you search the threads here (advanced search, "cooling system" and then pick the z3 forum to search), you'll find a ton of information.

I was chagrined to find that what I thought was a driveable car for the summer, actually had to be considerably restored. So now I'm deep in the middle, with parts going in and things getting reassembled in the godawful heat. I'd planned to do all this next winter in my garage courtesy of a propane heater and months. But no, its just got to be done now because if something breaks, often very expensive head damage is incurred. I proved it as I disassembled those two plastic connector pipes - both literally broke apart in my hands as I gently tried to remove them. Plastic embrittles with both heat and age and after 25 years, you drive at your own risk. My whole "scale" of the project changed as I got into this and my timeline extended. In part because I'm 65 and can't work as hard as I used to and because the heat limits the number of hours too. With any luck, I'll have her running in a week or two - but then I'll be doing just short trips to "test" everything.

If I ever buy another one of these and the owner can't prove the cooling system has been done, well, I knock a couple of grand off what I'd pay (the fair market value). I paid $6k for mine and if I knew what I knew now, I wouldn't go over $3500. That's the cost of learning.

[BimmerBreaker]

Thanks for the reply Cyberman, my 97 Z3 is the 6 cylinder 2.8L M52B28. Since I am looking into turbo kits, would replacing the cooling system with the intercooler work? Since I dont know what to look for, do you have any pictures to help me understand which pelican part would fix this problem.

Thanks!

No, intercoolers do not replace the cooling system

[Mr Bingley]

Welcome to the forum dshinR. Sounds like you're going to have big fun with this. Post some pics when you count is high enough. We have our own classifieds section where you should be able to find a mirror--maybe even in your color--you can post a "wanted to buy" (WTB) ad. Have you checked the fuse for the seat? The cooling system is where most people begin their adventures here. We have A LOT of resources available---you should start reviewing our faq section if you haven't already, and playing around with our search function. There isn't anything to do with your car that hasn't been discussed extensively, debated, tested, and written up--several times.

[dshinR]

Thanks for the clarification bimmerbreaker so intercooler is something added to the radiator? And thanks for the intro mr Bingley i will familiarize myself with the search option! Cyberman I will take further look into those things later tonight after the kids are KO. I did take a look at the trunk and it seems like some welding was done for the subframe reinforcement issue. Does this mean i dont have to do the reinforcement myself? How do i post pictures to show you guys what welding im talking about

[BladeRunner919]

Thanks for the clarification bimmerbreaker so intercooler is something added to the radiator?

Please don't take this the wrong way, but do you have any idea about adding forced induction to a car? I can see this ending with a very expensive and disappointing outcome.

[dshinR]

I didnt take it wrong way bladerunner as I am sure you didnt know everything in the beginning. This forum is actually where i am asking the dumb questions and looking up different stuff to get an understanding to avoid the disappointing outcome. As you know there are a billion posts on different forced induction builds and the “dont forget to do this” or dont do this threads so its hard to put all the pieces together. I will be reading up more and learning more from other peoples mistakes and also googling shit like where does the intercooler go. So bare with me brother. Semper Fi

[2002Z3]

THe advice I have to offer is to leave your car stock and just repair things that are broken and to do regular service. If you want more HP, sell the car and buy one that has more HP out of the box. It almost always costs more to add HP, than to buy it up front.

A 2001/2002 M54 engined Z3 is a great deal today. Just 13 or so HP less than a 2000 or earlier M roadster. 225 HP is a lot for a light little car. Your 2.8 has similar torque at the lower end, so it will feel nice at typical traffic speeds - at least in town. Getting on the highway, if people are doing 80 MPH, will be OK... but, a Toyota Avalon will pass you. So will a Honda Civic and maybe a turbo Hyundai.

[Mr Bingley]

Well, as long as you are looking to be informed, and are not put off by forum post know-it-all-ism, an intercooler, for what it's worth, is a heat exchanger that looks very much like a radiator of sorts, and typically (though not necessarily) mounts in front of the radiator and condenser. However, instead of cooling the engine coolant, it cools the air charge produced by forced induction. Compressing air increases the temperature of that air (pressure generates heat). Forced induction--be it supercharging or turbocharging--compresses the intake air charge and thereby increases it's temperature. The increased temperature can lead to pre-ignition (pinging), so the timing must be adjusted by the CPU in order to prevent this, negatively impacting performance. Simultaneously, cooler air is denser (more oxygen per cubic volume), and so cooling the compressed air charge means more air/fuel mixture enters the cylinder (more air = more fuel). For these reasons forced induction is more efficient and produces greater horsepower gains if the compressed air charge is cooled prior to mixing it with fuel. That is the function of an intercooler. The compressed air charge leaves the compressor (or kompressor in German) and travels through the heat exchanger, cooling it down on its way to the intake. A turbocharger set up with intercooling for our cars typically runs north of $10k as a DIY, and can run significantly more than that if you pay a performance shop to do it. Supercharging is more affordable, but even then a supercharger set up with intercooling (or aftercooling) is still north of $5k just to think about. Here's a good article on intercooling.

[cyberman]

I was going to offer the same advice as Steve with just a small addition: You have to be an apprentice before you can be a master. First learn the car inside and out as a "stock" item before moving on to more advanced work. I'm a retired mechanical engineer and my first time just stripping a simpler 4 cylinder down for a cooling system refresh is challenging. It's a great way to dive in and get a basic understanding of where everything is and what everything does. I'm glad I started with the 4 banger - no VANOS to worry about and 2 less cylinders to go wrong and replace parts. More room in the engine bay to work and a good way to get an understanding of the price of everything.

Ralph: thanks for the refresher.

And finally, I'm not into drag racing or raw horsepower any more. Anyone can buy and some people can build there way to horsepower. These cars are made for DRIVING and to me that means handling and I'm much more proud of my skills turning the car at speed than I ever would at the skill of stomping a gas pedal. Of course, the best is to have power, handling and driving skill. But of all these, power costs the most and I have to live within a budget.

[dshinR]

Cyberman, i definitely understand the driving aspect of it. I mean i took the z3 for a test drive and by the time i got back it felt so fun to drive the car i was biting my teeth. Next thing i know im looking at this forum 3-4 times a day.

Quick question for you Cyberman. Do i still have to replace all the cooling system if I dont see much overheating from driving a little faster?

Mr bingley, thanks for taking the time to explain all that. I am a chemical engineer so I kind of got the jist on the whole compacting more oxygen for that oxidation reaction burst. Im just mechanically challenged as i have zero experience. So I literally werent able to tell the difference of radiator vs intercooler based on what people were saying.

Quick question for you mr bingley, i see a turbo kit on cxtacing.com for around 1700-1800 is that not all that i need to turbo this current car?

[s8ilver]

Welcome to the forum. Post some pictures of your car when you can and ask plenty of questions here. There's a wealth of knowledge for sure.

The cooling system isn't really on a sliding scale. The temp gauge isn't going to tell you what part is ready to fail. It either works properly or it doesn't. Problem is, there are a lot of pieces that can go wrong if they're original (water pump, radiator & fittings, hoses, fan, fan clutch, the actual coolant itself) which is why we suggest replacing the entire system unless you have evidence it's already been done. What good is a turbo if you cook your head on your first pull?

Now, reality check. If you have $2000 to spend and are just learning what an intercooler vs. a cooling system is, you will not be able to add a reliable turbo system to your car for $1800. Where will you dyno the car? Who is doing the tuning?

You need to make sure the base systems are up to snuff first. Cooling system age? Condition of the braking system? How is the sub frame? What is a sub frame? Suspension...could you even put more power down if you had it? Tires? If you really want more power, sell the 2.8 and go for an M. It's a bit edgier and aggressive in just about every regard, and you get more power. The M54, as mentioned, is also plenty of car. Or, just learn to drive what you have to the fullest. It took me a long time to learn that. Power is cool. I get that. I have a track car that had 130hp NEW in 1991, at sea level. Now it's 29 years old, at 6000ft. It maybe makes 85hp at the wheels at my altitude, probably less. It's a darn hoot around the track, and I put down better lap times than cars with 3x the power. Power is meaningless unless you're drag racing, and a turbo 2.8 on stock everything else still won't be fast.

That's actually more fun than adding power, IMO. The 2.8 has plenty of power as is. Just go enjoy it. Oh, and fix the mirror.

[streetmaster56]

First post, new to this kind of stuff so take it easy gents.

Just got a 97 Z3 that had 70k miles on it.
It's got a little cosmetic problems like side mirror is hanging by tape, the place where u have your arm to flip up the soft top is broken, the driver seat doesn't move.

Either way, I am looking to drive this a couple years and have a little fun with it.

I did start reading at the different builds on the turbo section and I am looking at Garrett and CXRacing for some turbo kits for the near future.

I have about $2000 right now to have fun.

Recommendations? or even a path to a fun build?

Thanks for having me!

O, the card counter seems like he knows what he's doing. anyone know what type of builds he's done?

Welcome to the forum, just wrapping up my build, what ive learned about my adventure, is these cars are a blast to work on. I got mine a few year back, by trading my tj even up, at a used car-lot, and with 160k on the clock, it was in need of a bunch of tlc, but got lucky with having zero rust. One thing that everyone who owns a Z3, is faced with, is the issue of bad spot welds in the rear subframe area, so you might want to take a peak, although a couple of mine had some surface rust, but they cleaned up pretty nice, but will keep an eye on them from time to time. But that being said, the Z3 harkens back to the BMW 507, and from my under standing, is the last roadster built with that old school feel, along with a big car feel, so keep the dirty side down, and good luck with you new endeavor.

[Mr Bingley]

Quick question for you mr bingley, i see a turbo kit on cxtacing.com for around 1700-1800 is that not all that i need to turbo this current car?

Short answer: no. But that is a question better posed in the FI section.

[cyberman]

The message I got, repeatedly from current members and reviewing many past threads: Stop driving NOW and do the cooling system. The plastic cooling system parts embrittle over time and that's accelerated by heat. These cars hava a lot of time under their belt. When they fail, very often the head warps before the driver realizes it. And that warpage necessitates thousands of dollars in repairs.

So, that's what I'm doing. My car is in pieces in the garage as I work on it. It was a horribly bad surprise. The car ran well and I assumed I could toy around with it over the summer and then set about working on it over the winter. My parts total is around $900 and that includes all hoses (coolant, fuel and vacuum), a new water pump and radiator, new valve cover gaskets, and other things. There are plenty of "refresh" lists here.

Now the problem is that if you're not experienced with mechanical work - this is going to be a real hard job. In my youth, I was a decent mechanic and did similar things with the cars of the day. But cars have gotten a lot more complicated.

[dshinR]

Man, you guys are awesome!

S8ilver thanks for your input and the knowledge, i think im going to come off this buy a turbo right NOW mode and look at replacing things to make my car more enjoyable to drive. As it stands ive had three different people drive my car and they all said it was a good purchase no doubt. How do i upload pictures? I want to make sure the subframe was reinforced and the welding marks im looking at is what needed to be done.

Streetmaster56 thanks for Sharing your Experience. This forum is loaded with experience and knowledge. I am already having fun just cruising with the top down.

Mr bingley as always your posts are well taken into consideration.

Cyberman, I am planning to replace the radiator and the plastic cooling system parts. I have read the pelican websites and i will follow as much as i can.

This bring me to my next point. Since I am abandoning getTurboNOW plan, I am considering making this car more enjoyable daily. A buddy of mine is telling me his audi a4 has a phase 3(?) suspension system. What would be the equivalent brand on the z3?

[zellamay]

A few thoughts: Slow down, ask question on this site (which you are already doing). You will get more solid performance by good maintenance than by turbocharging a junker. You cold easily use all your budget on the stuff you've mentioned that needs repair. ....... Avoid "mods" for a while, while reading about them on this site....... Absolutely make the cooling system perfect before doing anything else. ...... Your subframe does not necessarily need reinforcement. Get somebody who actually knows what they are looking at to examine it, or post some really good pictures. ...... Lord knows what a "phase 3 suspension" is. At 70k your suspension is probably still in decent working condition, but before any "mods", replace any worn parts.

[dshinR]

Thanks zellamay, i am definable taking the replace cooling system seriously. I am looking to doing that and other things to increase the longevity of the car.

[cyberman]

So, good, you're on the right path now. It took me three years from ages 16 to 19 working in garages and fixing my own cars with professional guidance before I thought I knew something and tackled heavier jobs such as rebuilding engines.

Now your engine is different than mine, but here's what I discovered I'd needed late in the job and am now waiting for parts to arrive:

Valve cover (in my day we called it a rocker arm cover): Yep, the main gasket that goes all around is hard to miss. But don't blow off the small gaskets that go around the tubes extending down to the spark plugs. They have to be replaced since they leak oil down into the spark plug holes and ruin the wires (expensive). Also, and this is the one that got me. There are many bolts going around the cover and several in the middle. The all have little rubber gaskets and these all must be replaced to properly seal. And, all these seals not only prevent oil leakage, they also seal the vacuum and if air leaks around them, it screws with the sensor readings and can make a lot of problems with the computer control.

But the cooling system is where I really missed it. There is a site called RealOEM.com which has original drawings of engine subsystems, from which you can get part numbers. It helps you identify the parts you need and also see them in exploded view. It's a clunky interface, you have to pick the maker (BMW), then the year and pick "Classic" - then the engine, etc. But here's the thing: I found the seven coolant hoses that it considers part of the coolant system and thought I had it nailed. Then, when I got the engine apart, I realized I missed two heater hoses that aren't classified as cooling system parts in realoem.com. Now I'm waiting for those parts before I can continue re-assembly. I'm doing little things now, like cleaning the engine down were you can't see it, using the wire brush wheel on my bench grinder to polish up bolt heads, stuff like that.

Here's my philosophy: replace all rubber and plastic that could possibly fail. That includes the fan blades which, yep, were manufactured in late 95. I'm told it's not as big a problem on the 4-cylinder engines (M44), but why take any chances since I'll probably drive this thing until I die. I could see problems in 5-10 years if I'm lucky enough to live that long.

Things not that critical and not too hard to do, I'll put off for a while. Namely getting the injectors cleaned and flow tested, and much of the body stuff such as the seat bushings and upgrading the audio system. But the job of replacing the cooling system is a big pain, so while everything is apart, inspect and replace everything within reason. The power steering pump lines leak a bit, but other than putting some extra clamps on the reservoir lines, I'll wait on that. Vintage suggested the replacing the gasket under the oil filter mounting bracket and I would have done it except it's too damn hot right now.

I'd planned to do the standard tune-up (coil pack, wires and plugs) later, but since I found my coil pack is damaged, I decided to do it now. In the end, everyone has time and cost budgets, so some compromises have to be done. Down the road, I might buy an engine and just rebuild it out of the car, I used to do things like that. But, if anything, I'd probably try to find a 6 cylinder, maybe a Z4 or something like that if I had the money.

And, plan to buy some tools if you don't have everything needed. There are big allen sizes you'll probably need, maybe a cheap fan bolt tool, etc. I just discovered I need some type of special tool to remove the clamps on the fuel lines down low on the firewall. I'd seen references to the special tool needed but thought I was home free when I found normal clamps on the fuel filter lines. But nope, not so fast. The fuel filter was probably replaced and new, normal clamps installed. But my guess is nobody ever got to the rubber fuel lines behind the engine (although it looks like they could be serviced from underneath the car). And, since they have the original clamps, they're probably the original rubber - so now I'm off to find that tool, which I may never need again and for that I have somebody in BMW engineering to blame. Why are the different than usual? My guess is that they are quicker on the assembly line and saved maybe 50 cents on labor costs (per car).

Anyway, have fun, it's a good hobby.

[dshinR]

Does anyone have the pdf to the bmw z3 1996-2002 service repair manual? Or know where i can get it? The one i see online says in review its “disappointing” lol

[cyberman]

The Bentley manual is often recommended. It runs $80 and up and is widely available. I have the Haynes manual, which is still in print, but it's "disappointing".

[Mr Bingley]

Check out this thread and especially post 11

[cyberman]

Thanks Mr. Bingley! Just ordered it - cost was $15. And yes, I'll do the same, just print out as needed. I tried to put something together from Pelican Parts, but it was a real PITA.

Now, if only I'd numbered all the connectors.. a little masking tape along with pics would go a long way....