Wheel + Tire Sizes / Options

[Norm!]

@tferrer - 225/50-15" tires are almost 1" in diameter too small - only 23.9" diameter. here are the recommended sizes in 15" which more closely correlate to the 24.7" diameter of the 195/70-14" original tire
205/60-15 -– dia. 24.7”, width 8.2" / tread width 6.8", circ. 77.6”, rev / mile = 842
215/60-15 -- dia. 25.1", width 8.7" / tread width 7.3", rev / mile = 827
225/55-15 – dia. 24.7”, 77.7” circ, rev / mile = 842 <caution - tire is 9" wide - not many tires available in this size>

I went with 205/65/15 Michelin Premier A/S on my 15-inch BBS RZ that I refinished from gold. They are 25.47” diameter, 8.2” section width and 7.7 tread width. These are only 0.12” taller than the Michelin XWX 205/70/14 put on the CSL do I figured they would be OK and so far no fit issues. I like the way they fill the wheel wells and provide the ride comfort of a 14” wheel.

 

[Ohmess]

I went with 205/65/15 Michelin Premier A/S on my 15-inch BBS RZ that I refinished from gold. They are 25.47” diameter, 8.2” section width and 7.7 tread width. These are only 0.12” taller than the Michelin XWX 205/70/14 put on the CSL do I figured they would be OK and so far no fit issues. I like the way they fill the wheel wells and provide the ride comfort of a 14” wheel. View attachment 107596View attachment 107597View attachment 107598View attachment 107599

Glad to see this post. I looked at the 205 65 r15, but was concerned about the increase in rolling diameter and went with the 205 60s instead. I am running on Carl Nelson lowering springs, so this may be a closer call for my car, but I am a fan of Michelin, and the don't offer anything in the 205 60 r15 size.

And I too like both the look and ride comfort of 15s over anything larger, even though tire selection is not as robust.

 

[Norm!]

Glad to see this post. I looked at the 205 65 r15, but was concerned about the increase in rolling diameter and went with the 205 60s instead. I am running on Carl Nelson lowering springs, so this may be a closer call for my car, but I am a fan of Michelin, and the don't offer anything in the 205 60 r15 size.

And I too like both the look and ride comfort of 15s over anything larger, even though tire selection is not as robust.

I was little unsure about the size also but decided to try them. One reason I took the leap is the unavailability of the Michelin’s in 205/60 series. I talked about it with OCcoupe and he agreed I should be fine because they are so close to the CSL diameter. I am careful at driveways. They only change the speedo two mph at 70 and our US 3.0s are geared lower than Euros. If I ever lower it I would have to add camber plates since the front tires do stick out past the fenders a bit. I wouldn’t want to role the fenders on such an original car.

 

[eriknetherlands]

Just something to add wrt original Alpina CSL wheels. I picked up a set, knowing one was an FPS, but the other three classify as 'type 2' following the definition in the initial post.

All three wheels have " Alpina, 110344, 7jx14H2 and 2800200" on them, and all of them have different date codes. In the pictures I've placed a small green piece of tape pointing at the "Alpina" text.

RSPorsche identified in post 1 of this thread already that the valve position changed relative to the "Alpina" text:
3 versions are known (sofar) With the valve set at 06:00, the "Alpina" text appears at 11:30, 14.00 and 19.00.

editted feb 2021: One of my wheels clearly has the valve at 16.00.
(this is a mistake form my side; i reasoned here 'having the Alpina text at 12:00, where does the valve sit?'. whereas RSPorsche defined it as 'with the valve at 06:00; where does the 'Alpina' text sit. Using the right (RSPorsche's) definition, my wheels aren't different. see updated list below. )

However I noticed there is another difference: the "height" of the spoke relative to the edge. One wheel has 10 mm, where the others have 5 mm spoke height. (See pics)

I have the following three differences in the wheels.
(edited feb 2021)
Wheel 1, valve at 16:00, with valve at 06:00 the "Alpina" text sits at 14:00 , dated 8-73 spoke depth 5mm
Wheel 2 valve at 18.30, with valve at 06:00 the "Alpina" text sits at 18:30, dated 4-73 , spoke depth 5mm
Wheel 3, valve at 11.30, with valve at 06:00 the "Alpina" text sits at 11:30, dated 7-72, spoke depth 10 mm

added feb 2021: Can other members check which date codes they have and measure their spoke height?

So, perhaps to be able to identify a correct set, you need to align many things: date stamp, part number, KBA approval numbers, valve position and spoke height.

 

[Markos]

@eriknetherlands,

Your transparency and analysis is commendable!

 

[E3-3.0Si]

The key is that you want M12x1.5. I think that the splined shoulder on wheel studs is for the most part, consistent across all metric studs. One of those part that you pick the diameter and the length and you should be good to go. Find the stud online and check the length of the shoulder to ensure that it won't under engage the flange. Likewise, make sure the shouldn't isn't sticking out too far. The dimensions should be listed. I'll try to take a measurement of the studs on my spare axle. Gimme an evening or so.

Hi Markos, did you get the opportunity to check the measurements at all? The reason I ask is that I don’t want to spend over £160 on a set of 20 of the ARP studs only to find that they catch on the flange! Many thanks, Tony

 

[Markos]

Hi Markos, did you get the opportunity to check the measurements at all? The reason I ask is that I don’t want to spend over £160 on a set of 20 of the ARP studs only to find that they catch on the flange! Many thanks, Tony

Hi Tony,

I just measured 38.75mm from end of stud to flange. This is for a disk setup, rotors removed.

 

[paul cain]

At Chris' suggestion I am adding this to the thread.

 

[HB Chris]

Thsee are late 80s/early 90s italian repros from Rivi&Grimaldi. The Design is similar, yes but not the same as the Ronal/Pedrini (FPS) produced orininals. Note that the offset here is 10mm, just as the more common version from Rial.