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The CD-35 1973 offset was 22mm, not 35. Thanks for this chart. I'll try and measure one of my ca. 84's. They are touted as being lighter also. Cheers, Bruce
 

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CD-35's Weights

My research in old parts catalogs indicates that Cromodora Daytona's were "magnesium"-based alloy up to about 1985. An IAP 1984-1985 catalog says, "CROMODORA wheels are die cast MAGNESIUM for a smooth finish, attractive appearance, light weight, and extra strength. They are approximately 2/3 the weight of a comparable aluminum wheel." (Notably I paid $362 for a set then.)

They disappeared from the catalogs after this (~86-87) and reappear in an October 1987 Shankle catalog as "new aluminum reproductions" without the CROMODORA name at $88 each. Even Shankle's June 1987 catalog did not list them in any fashion.

I have an April 1973 version (date stamp on back) spare, and photos and records of a December 1976 version (photos below). While the face and back markings were a bit different, they are both 12 pounds. I shipped the 1976 to an aerospace engineer in Seattle who said he could fix it (bad curb rash). I await his answer. I bought the 4 on my car in April 1985 but have not had them off recently to check their date stamp or weight. When I do that, it will establish a later model CD-35 weight for sure (and date stamp).

One could devote a thread to just CD-35's but that's not the intent of this thread. I'm sure someone in the business back then who dealt with this in detail could shed some light on the changeover and some metallurgist on the exact nature of the differing alloys. The bottom line IMO, in my mind there is ~pre-86 magnesium-based alloy at 12#, and post-86 aluminum-based alloy at 16# (for a 6x14). Even the new IAP repros are 16#.

I have corresponded with some who insist the earlier wheels were NOT magnesium. I'll leave that to the experts. That is why I say "xxxxx-based alloy" above. I took some metallurgy courses a long time ago and know you can mix different proportions of aluminum and magnesium to achieve different ends (weight, strength, ductility, etc.). One clear end is 12# versus 16#.

As Joe points out above, the were first seen in 67 on the Ferrari (365 GTB-4) Daytona, so that is an early date point (size and bolt pattern notwithstanding).

Adder: One thing you will note in the photos (and it is clearer in person) is that the 4/73 and ~84 have sharper edges on the star and circle corners. The 12/76 is noticeably more rounded. Interesting as it is in the middle of those two other dates. Markings differ on all 3 also.

OK experts with facts, weigh in here. Thanks, Bruce
 

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i hear the newer daytonas arent event magnesium anymore?
It is true the new Cromodora Daytona reproductions are not magnesium, but there are very few if any modern road wheels that are. It is just not feasible to use this material for a number of reasons.

Of course - the old ones were magnesium alloys (i.e. not pure magnesium) and the new ones are aluminum alloys - and I'm sure the exact composition is a fairly close secret.
 

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first seen in 67 on the Ferrari (365 GTB-4) Daytona, so that is an early date point (size and bolt pattern notwithstanding).
Unless of course one has ever seen the wheels used on the 1966 Ferrari 312. (though they were usually anodized gold rather than silver)



Or the 1965 Ferrari 365p Berlinetta Speciale



Suffice to say, the pattern/design existed before the Daytona car and likely the wheel 'name' is something that Americans came up with after seeing that style, for quite likely the first time, on that car in '67. (unless of course they've always called them 'Daytona' in Europe also, in which case that theory is out the window :) )
 

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OEM Spider wheel is "Daytona"; not "look-alike"

Don't know when the name "Daytona" was first used. However, FTR, the OEM Campagnolo 5-star wheel used on the Spiders from 1982 through 1985, inclusive, is officially called "Daytona". The Alfa literature documents this clearly. I think it is misleading to call it a "look-alike". From 1986 forward the OEM 5-star wheel used up to and including 1994 Spiders, was made by FPS. This FPS edition is identical to the original Daytona, but it is referred to as the "5-star". Granted that Cromodora also used the name "Daytona", but they never supplied an OEM 5-star wheel for the Alfa Spider.

Best regards,
 

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OEM Spider wheel is "Daytona"; not "look-alike"
While "look-alike" is perhaps a bit harsh, it is very obvious the wheel is derived from the Cromodora.

Since it does have it's own style with the deep trough around the rim, perhaps calling it an "Evolution" of the Daytona instead of a "look-alike" would convey the same meaning without being derogatory?
 

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While "look-alike" is perhaps a bit harsh, it is very obvious the wheel is derived from the Cromodora.

Since it does have it's own style with the deep trough around the rim, perhaps calling it an "Evolution" of the Daytona instead of a "look-alike" would convey the same meaning without being derogatory?
Why not use the correct name - the one that is used in all the Alfa literature? I think we do ourselves a disservice by trying to come up with different names. If two manufacturers use the same name, we should be able to handle this... I say we increase our knowledge base and show it by using the correct names, with additional adjectives if necessary, i.e. the OEM Campagnolo Daytona, the aftermarket Cromodora Daytona... :)

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Like I said above, this could spawn a separate thread and lots of debate about alloys and content, and now names. I agree it should be the name the manufacturer officially gave the item, and say a common usage name e.g.,"phonedial"?). Just specify the mfg in the table and the name/nickname/date/model/size/bolt pattern/etc. to differentiate it. The thread is not about naming them, it's about adequate ID and weights. I was only trying to add the nuance that the mfg. date, among other parameters, makes a difference in weight as davbert's post above points out for BWA's as well. Keep the data coming; good luck to Jason sorting it all out!! Thanks,
 

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A few more wheel weights - most numbers from homologation documents.

AR GTAjunior steel 5 1/2x14 17#
AR GTA magnesium 6x14 11.5# offset 38mm
AR GTA magnesium 6.5x14 12#
AR GTA magnesium 7x14 12.5#
AR TZ magnesium 6x15 12.5#
Alfaholics GTA aluminum 6x14 13# offset 33mm
 

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Alfa Romeo 1300 GT junior 1966, stock 15 x 4,5 with 155 Firestone F560: 15,2 kg (wheel, tube, tyre, weights and valve). And yes, I know the Opel type flasher is not original...
 

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Jason, on the wheels table I would either add a manufacturer, or change "Brand" to manufacturer. To resolve Joe Cab's concern (partially) one needs to separate an "OM" from "replica manufacturer". The following wheel is the example:
Cromodora CD-35 Replica 14x6 4x108 23 16 lb. Style C from IAP catalog

It is not a Cromodora Brand or manufacturer. Also, may suppliers may carry this repro/replica wheel so a supplier designation may not help. For accuracy.

Thanks for considering this. Nice work! Bruce
 

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Giulia / Giulietta Borrani wheel weights

Asked for comments on Giulia / Giulietta wheels, 4.5 x15, Borrani and Fergat, I was TOLD the Borrani's were the wheel to race with as they were lighter than Fergat's. I do not know if this is true, however, racing in the late 60's with my Giulia spider, I had a collection (still do) of Borrani's. Found I could sometimes bend one in front, at the spyder with the right combination of tire and track surface. Not the rears. My car had, first disc front brakes, and later 2 shoe drums. Could not bend them all, only some, even on the same day & track. Later I found others were breaking, or cracking Fergat's at the spider, and sometimes at the lug holes. Perhaps the Borrani's were not lighter , only more bendable! :rolleyes: I guess this is a good thing.;) Better a front end shake, than a front wheel leaving the car, and you in never-never-land:eek:! Later we were allowed to widen our steel wheels, and most widened Borrani's again. I went to Minilites when rules allowed.
The stock Alfa 4.5 x 15 Borrani weighs 17 lbs. I just weighed one from my collection. Hope this helps. :DGordon Raymond
 

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Stock S1 Steel Wheel

Weighed a stock steel '69 Alfa 5.5x14 steel wheel without weights or stem. Same as S3 listed at 16#. It's interesting that there is no weight advantage with most of the wheels listed. Only some of the very early mag allow wheels come in at 11-12#. That makes it pure aesthetics and not function. :rolleyes:
 

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Plus possible width advantage, depending on fit.
Gordon Raymond
 
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