I'd like to see some Meraks!

I have no idea, surely they are older than 2 years or so. They seem fine, without any scratches or imperfections, but I don't know how good is the rubber.

I've driven various cars and been a passenger to others and even a Ghibli I with similar tires seems wobbly to me.

Maybe there is nothing wrong with the tires or the cars, but with me? I'm probably comparing it with my GranSport, which is rock solid, so cars with a 70 profile tire seem wobbly? I don't know...

 

If you're running XWXs they are a very stiff tire but hey are still a 70 series tire. They used to charge extra for mounting them because the sidewall is so stiff. In their day they were good for 200mph too. But unfortunately they didn't begin to squeal and break away gradually it was more of a snap and you were going backwards. If they're in good shape they should track very true. Check the production date on the tire.

There aren't a lot of choices out there. Coker also offers the Pirelli P4000E which is a 225/65zr15 and I'm using those on my Espada. They're fine but I don't flog that old beast around either. They're a fresh run and they're $64. If you have to have the concours correct XWXs then go ahead and pay through the nose but I actually prefer these.

I used to run 235/60ZR15F and 245/60ZR15 rear on my Bora so I'm pretty sure the 225/65ZR15 will fit the Merak just fine. A very close match to 215/70ZR15 in diameter.
There's nothing in 205s for a 70 series in reasonable tires.

A Merak isn't going track as well as your Gransport EVER it's older and it's rear engined. You should try a Bora at 160, it dances back and force about an inch, horrible aerodynamics.

That's part of the challenge with vintage cars!

 

well, currently I'm in the process of finding proper tires for my BBS 16" wheels, but I've discovered that there aren't many options out there for 16" wheels. At least, I can't have the 225 front 235 rear that I want (no single brand makes both), so either I fit different brands, so I have to fit 225 on all 4 wheels.

I will probably go for a 60 profile, since a 55 profile is even rarer on those dimensions, plus the 60 profile brings my 16" wheels to the overall dimensions of the original 15" wheels with 70 tires.

Sounds like the problem is with me and not the car or the tires...

 

Maybe, it's hard to say sitting in chair typing away on the the other side of the Atlantic.

The car should feel quite stable and precise at speeds where aerodynamics aren't as much of an issue like 130mph and below. If not, there could be a lot of things to look at.

Yes, 16" rims are tough. I think you have to get to the 18" tires to have any selection and expectancy that they'll be available for a while yet.

The 235 60 series are still too small for the rear and 225's are way too small. We used to see 235x60 on all four wheels on Boras and Khamsins years ago because they were readily available but they looked under sized and they were. The speedo will be off but so what if it's all you can get. It should be close to a 27" diameter in the rear.

Best of luck sorting it all out. It might take a bit of doing. More of that "fun".

 

I've done a bit more research and here is what I've gathered.

If I fit the same tires all around, I will loose the symmetry that the original tires have by using different sizes front-rear. Considering that I went from a 15" wheel to a 16", I have to calculate the differences and compensate for that in the tire.

So, if someone wanted to fit larger tires on the 16" wheels, then after calculating the ratios and keeping the SAME radius for all wheels (that is why the front has +5 profile, the result is this:


original size
195/70 VR15 (front) and 215/70 VR15 (rear)
diameter: 654mm, radius: 327mm (front), diameter: 682mm, radius: 341mm (rear)

new "sensible" size
205/55 R16 (front) and 225/50 R16 (rear)
diameter: 631mm, radius: 316mm (front), diameter; 631mm, radius: 315mm (rear)


Pros
- Stability
- Nicer looks, don't look like big balloons
- Bigger tread width
- Common tires available by various brands

Cons
- They don't "fill" the wheel arch since they are just a bit smaller
- They lower the car height by a little bit
- The new tires are 3.4% and 7.4% smaller, thus the speed needs a bit of adjusting.


Unfortunately, there aren't many other sizes to fit 16" wheels, so the next step would be to use 17" wheels. So keep that in mind if you are planning on changing your originals with something larger.

Finally, there are other sizes that aren't so "sensible", they would fit the Merak but they may not match the character of the car.

 

Do you still have the original rims?

 

Yes of course, that is what I have on the car right now. I'm just doing research before fitting the new BBS 16" wheels.

 

Why don't you try a set of the P4000 from Coker tire or maybe they're just as inexpensive in Europes from someone? For $240 which is less than 1/2 price of an XWX you could see what an original style tire is like on that car. They look old style too as they don't have that huge P4000 molded into the sidewall like the 215/70ZR15 p4000s did. Great for a concours? I wouldn't make such a big deal about the staggered size though a little bit narrower in the front would make the steering easier. We tried all kinds of tires ever since the mid 1980s and the best to come out were the old Michelin XGTs, mu god waht an improvement over the original XWXs. Those were put on in wider profiles in a 60 series tire and back then we WERE trying to drive the cars hard.

Did you just happen to get the 16" BBS rims because they were available?

 

staatsof, I want a fairly modern tire because I drive my Merak quite a lot (last trip was 3000km). Now the car is with my mechanic for some maintenance and getting ready for the summer. Thus, I need good tires that offer proper safety.

I selected the BBS 16" wheels because I've seen Walter's car and they matched the character of the Merak nicely. They are also WIDELY available everywhere because all
80's BMW 5 series cars have them (or most of them). Everywhere I looked, I found
stacks and stacks of them in several variations: 16" or 17", with 4 or 5 bold patterns.

I bought my set for 300 euros, plus another 200 getting them into shape (resurfacing, electrostatic paint, trident emblems, etc).

Eventually, if I don't like them, I can just give them to someone else and go for something different.

 

Walter has 16" rims on his Merak? I thought they were 18"?

That's a great price.

The P4000E is a relatively modern tire originally for the Jag XJ but it's no corner grabbing monster. Why would you think they weren't safe? Go look up the specs. The car would look very original with those on the stock rims and should drive nicely. Not for the track but a reasonable choice for shows that's all.

 

no idea, maybe he can tell us his specs and his experience with such wide rear tires.

well, why should they cost more? They are widely available by the thousands... just about every BMW dealer with old cars should have stacks of them and they are very old and outdated. Nothing special that people would be interested in buying these days, except maybe by some weirdo with an old car (that would be me...).

Oh, I didn't explain myself, sorry my mistake. I am doing this because I want to keep my stock rims with the original XWX tires in storage, I don't want to drive around with them, in case I scratch them. As I mentioned in another post, I do a lot of driving (life is short, eventually I'll die some day and I'd like to have driven and enjoyed my cars as much as possible!).

I see many people who store their cars for years and years and eventually end up too old to drive them, not something I aspire to do. I also see a lot of people who buy their cars, keep them hidden and garaged and eventually sell them for profit, again not something that I aspire to do (I have a real job).

So, by doing a lot of driving, I don't something better than the 70 profile tires. I am hoping that the Merak will behave better at high speeds (ok, it will never be like my GranSport..) so a niec 16" set of wheels with modern tires should do the trick.

I hope anyway

 

There are high performance 235/6016 tires out there and those are 27" so you should be good on the rear at least.

The PCD and bolt pattern matches a Merak on those or are you doing something else?

Keep us updated I know gcmerak is watching closely ...

 

I couldn't find tires of the dimensions you mention above, what kind of brand did you find with 235/60 R16? My searching found zero tires.

I made a small modification to match my caret and 4-bolt pattern, quite easy really, attached picture.
Image Unavailable, Please Login

 

Hi Maserati Blue,

Have you seen this: http://www.pirelli.com/tyre/ww/en/news/2011/10/07/pirelli-presents-p7-corsa-classic-the-tyre-designed-for-the-most-prestigious-historic-rally-cars/#.TxaBhqVhtvw

Pirelli will start production of high performance tires with classic pattern and dimensions.
I know Michelin do the same, but the prices are at the same level as XWX.

I think you have found wheels with a great design for Merak, but are you sure it's the same kind as Walter have? I think he has three piece split wheels in 16", and those are not cheep.
I like the brutal looks of Walter's car, but choose to keep my car original.

Best regards
Marius

 

The above tires from Pirelli come in ridiculous sizes: 255, 285, 305, 315... waaaay too large for the Merak. The 235 one looks good and should match the rear wheels nicely but it's for 15" wheels only and the 45 profile is just too small for the Merak, it will leave a huge gap in the wheel arch.

That is correct, Walter's BBS wheels are the "larger" model. I had the opportunity to see them up close at the 2010 International Rally in Sweden and I found them "brutal" as you mention, so I went for the same model but smaller variant.

The good thing with my BBS wheels, is that they resemble the original "looks" of the car, since the 16" doesn't make much difference. I also opted to paint them with the original silver color of the Campagnolo's.

So when you look at the car from a distance, it won't look out of place.

I will never do anything to my car that is not reversible, so playing around with various wheels is not a big issue. I'll try them on and see how the car behaves (and how it looks).

 

Bridgestone

http://www.tirerack.com/tires/TireSearchResults.jsp?customSizeSearch=&width=235%2F&ratio=60&diameter=16

 

Thanks for that, it seems different regions offer slightly different stock, since that tire wasn't available when I was looking.

I also noticed that the dimensions 235/60 R16 produce a circumference of 27.1 inches, which is larger than the stock (215/70 R15) tire circumference 26.9!! that is a laaaarge tire

 

Oh Yeah!!!! Gcmerak is watching very carefully.

Have to agree with Maserati Blue - Drive those bad boys and enjoy.

Ciao,
George

 

Every manufacturer's tires are different in dimension even if they are the same official size.

That's damn close. I think they have some smaller sizes in that same tire for the front too.

How great a tire that is for handling I have no idea.

It's all relative anyway. The Merak and Bora aren't terribly terrific track cars is stock guise anyway. They lean one hell of a lot in the turns. Nothing like the modern stuff so I imagine this tire might be plenty adequate. Certainly better than the stock XWX tires or even those P4000s. Without some modifications you're not going to be flailing the thing around a track as well as your GS goes and that's not really a track car either. Once you've had a drive in a purpose built race car it all seems very different. Enjoy it for what it is, a sexy looking GT car that's very enjoyable when driven fast within the car's limits. You won't be out dragging any Z06 or out handling a late model M3. So what.

Hey guys, does the Merak have the rounded tire rub ridges on the inside of the rear tire wells like the Bora does?

 

Absolutely right, I am not creating a track car. I'm only trying to improve handling of a GT
car, a bit more stability at high speeds, that sort of thing. During the process I'm also
making it look a bit more modern with the BBS wheels.

 

As for the stability during high speeds I doubt you'll do any better than the XWX tires.

A friend of mine an I used those on a 1990 Q45 in the Nevada Silver State open road race. Top speed was 165mph in that car. We wanted a tire with speed and load rating plus they track really really well in a straight line. That course only has one set turns over 90 miles so it's mostly a straight, flat out course.

If your car is moving around at high speeds I don't think it's a tires issue. Keep looking.

But the newer tires and rims will make a much better turn negotiator and XWXs ride very harshly. So it should be a big improvement.

 

What's been done exactly?

 

well, I don't know yet, once the wheels are ready and I test them, I'll be able to see the difference and report back to you, right now I'm only guessing...

 

They "filled" the original 5 bolt holes, then did some processing and punched 4 new ones to match my Merak.

I'm sorry I can't explain it with technical terms, English is a second language to me. I know they had to do some extra work, sanding, electrostatic paint, that sort of thing. They also did some calculations so the wheel fits exactly in the same position within the wheel arch as the original wheels.

Now they are ready and I'm waiting for the tires and the trident emblems. The whole thing should be ready sometime during the next week, but I still won't be able to drive the car because I am also doing other maintenance things.

Overall the car didn't need anything except some work on the air conditioning system, otherwise the car is perfect. Initially I was surprised why 2 people who looked at the car didn't buy it before me, but I found out they didn't like parts of the paint. Which is good news for me, I managed to get my hands on a 1983 Merak SS, which is one of the last 20 Meraks produced by the factory, just because the previous guys didn't like the paint.

To be honest, the paint needs some work, it seems the previous owner did a re-spray
and while the guy who painted the car did great work (no bubbles, etc), the guy who
did the sandpaper thing before the paint, did a bad work and left scratches. So the
paint has some small imperfections here and there.

Which of course is a small thing considering the whole car is perfect, every button works, every electrical component works, the interior is superb (apart from 2 small scratches) and the body is with zero corrosion and zero rust.

Anyway, I can just repaint the car any time I want, but I don't think I will, the small
imperfections on the paint are too small and would only bother someone going to
a competition.

Since the car is in such good condition, I decided to work on things that aren't broken (uh oh...), first the air conditioning system needed some work, so I took the whole thing out and converted it to a new Sanden SD7H15 compressor with 7 pistons. I also switched to the new freon type to work with the new compressor.

Which also led me to remove the refrigeration unit and refurbish it. I found that the flow was a bit obstructed, so that should be fixed now.

I also changed the gears in the electric windows, to the fully metallic ones.

Changed the Choke cable because the previous one was a bit "sticky".

Refurbished the whole braking system, painted the calipers and changed all rubber things on them. Previously the calipers were a bit rusty for my liking.

Ok I'm fixing things that aren't broken but I want to occupy myself during the winter

Oh, did I mention that I removed the interior, removed the rear seats and the "doors" to the fuel tanks? I then insulated everything from the start, added Dynamat extreme and filled the void between the engine bay and the gas tank enclosures, so that water and fumes don't seep through.

I'm probably forgetting some other minor things...


PS:
When I removed the interior, I found out that the speakers are not original, they are after-market from the 80's. They sound nice and they are well hidden around the area of the rear seats... I haven't decided what to do with them, remove them for a complete original car or keep them since they are "period" and not something fitted today?

PS2:
I'm not sure how I started to reply about the wheels and ended up writing the above essay... sorry for that!

 

I'm sure most folks on this thread rather enjoyed your description of making things better.

I've not heard of doing that to a set of wheels before ... ?