Hellebore wheel help

[Alex]

Please take a look at the thread I started this morning in the GT section regarding a Hellebore wheel which I recently purchased. I need help to identify what I have, as it differs in some respects to the very similar and more commonly known GTA wood-rimmed wheel. Many thanks!

[alfazagato]

GTA steering wheels have 7 holes, 2 per spoke and one at the top.

[Alleggerita]

Originally Posted by alfazagato

GTA steering wheels have 7 holes, 2 per spoke and one at the top.

Not necessarily. There are quite a few GTA's that have wheels with 6 holes and without an aluminum ring - both in small and large diameter - am familiar with a few cars equipped like that.

[CanAmBob]

Originally Posted by Alex

Please take a look at the thread I started this morning in the GT section regarding a Hellebore wheel which I recently purchased. I need help to identify what I have, as it differs in some respects to the very similar and more commonly known GTA wood-rimmed wheel. Many thanks!

I purchased one just like this from James Weber an Ex ARI executive and kept the horn button and sold the wheel and hub. The history of the wheel per James Weber is that he bought the steering wheel from Knauz motors in 1968 and said it came off a GTA. James said that it was a legitimate GTA option. There seems to be a lot of folk lore about GTA options. I was told that GTA's only had 14 inch steering wheels. Yet when Horst Kwech gave me the original Steering wheel for my GTA that he removed in late 1966, it measured 15 inches, it is however 7 hole. I found a photo of the six hole wheel on a TZ in an early era photo but can't find it.

[alfazagato]

More confusion. When I have been in Italy at Monstro Scambios I have been offered used 6 hole "GTA" wheels and told that the only difference is the 7th hole. The interesting fact is that these wheels were a fraction of the price of a 7 hole proper GTA rim. I took a tracing of the 6 hole layout and compared it with the 7 and as far as I recall they were similar. The 6 hole wheels were being sold as for a variety of cars subject to boss arrangements and were certainly non-specific until I mentioned GTA.

[jimcra]

CanAmBob, Nice article on your McLaren M6B in this months Vintage Motorsport. Congrats..

[CanAmBob]

Originally Posted by jimcra

CanAmBob, Nice article on your McLaren M6B in this months Vintage Motorsport. Congrats..

Thanks for the comment. D. Randy Riggs really liked driving the M6B. BTW Randy is doing a great job for Vintage Motorsport Magazine and the vintage racing sport.

[Alex]

Thanks for all your suggestions, guys. I've had some off-BB contact with someone whose knowledge I respect, and he also thought there could be some TZ DNA, too. I'm open-minded about it, though, and I guess that further research is needed - period photos and suchlike (did the TZ have a full parts book and, if so, who has one?).

And yes, Stuart, we've all had moments like that at mostre scambio ...

[richards]

Hi

This is an absolutely standard TZ wheel (the boss is quite different) - all the dimensions fit my TZ wheel which is sitting here on my lap! Even the number 6 1 on bottom spoke reverse is the same. However there is one odd differences, mine lacks the outer 9mm spoke hole!

However, fyi the TZ Uso e Manutenzione shows a 4 hole wheel in all drawings and the shop manual the same. The part number is 105.10.23.051.01. No alternative sizes are shown in any TZ racing documentation I have.

I have no explanation as to why my wheel has only 3 holes per spoke, I have never seen another like it. I can vouch that it was on the car in 1970 perhaps it was replaced in 1965 when rolled, however fotos reveal only superficial damage....

Like most other owners I use a smaller - 34.5cm (standard 38cm) - wheel, identical but without the Hellebore imprint, I guess a replica.

Richard

[Alex]

Richard,

Very interesting! So your wheel has the 6 black Allen screws too? Would be quite interesting to know in which respects the boss is different to mine. Does it have the alloy retaining ring as per the regular GTA wheel?

Alex.

PS - I was also told yesterday that the TZ column spline might be slightly different to the regular 105 Burman box. I'm not sure if this is correct as I've never been able to make a comparison, and I must admit that I've never measured mine. But 20mm is the clue ...

[richards]

The numbers are slightly different - mine reads 6 1 - though the type face is identical. When you get old it is easy to confuse 6 and 9, perhaps even when young. This difference perhaps suggests perhaps mine is not official TZ issue but an original Hellebore product nevertheless.

On another the original wood colour - stain? - is a much lighter shade which I think benefits the look.

Richard

[Alleggerita]

FWIW the catalogo parti di ricambio for Giulia TZ shows a 7 bolt wheel w/ aluminum ring and 4 hole spokes part # 105.10.23.051.01. The TZ parts catalogue also shows hubs in four different lenghts, 34, 49, 64 and 79mm (79 supposedly being standard).

I have seen both 6 and 7 bolt wheels both on TZs and GTAs, also 15" and 14" diameter - 15" is stock on GTAs, but there are ones with 14" wheels as well. Most 14" wheels have 3 holes in the spokes but I have seen 14" wheels w/ 4 holes as well. I believe the number on the bottom spoke refers to who assembled the wheel. Also hubs tend to be specific to their wheel w/ bolt holes between wheels being slightly different - yes you can usually fit an wheel to a different hub by slightly filing the holes. The wood rims are sometimes thicker and sometimes thinner, some of them stained lighter and some of them darker.

From what I have seen, I would say all types of wheels were fitted to the different cars.

[richards]

Hi Alex

Nothing is as simple as it seems. The good news is that the foto of your boss is very similar to the line drawing in the workshop manual, no rubber boot is shown but clearly visible is a groove around the boss.

Now why mine differs to yours is that 4 different lengths are shown;

34mm - on request
79mm (spostamento volante +45mm)
64mm ( ditto +30mm) on request
49mm ( ditto +15mm) on request

According to my online translation spostamento volante is flying wheel - which I guess means the actual distance the steering wheel moves by varying boss length.

I also know for a fact that there are AutoDelta modification bosses to give other alternatives.

This would suggest that 79mm is standard, forgotten what length yours is! The boss I have here is 64mm long and is a two step affair starting a diameter of 71mm straight for 15mm, then a steep curve and gentle taper to a diam of 58mm for a length of about 32mm followed by a very gentle curve of length 17mm to a diameter 34mm. Length 64=15+32+17 about!!

Now as regards the fixing, from my experience there are no black fixings anywhere on a TZ - stuck my neck out here - and also no hex type heads either! Mea culpa if incorrect! My wheel is attached by chrome very shallow round headed slot screws, no spacer mounting ring, wheel attaches straight onto boss, the racing type horn button simply pushes into the boss and secured by a captive spring around circumference. This differs to the parts manual drawing which shows a 6 hole spacer ring which holds the horn button. The 6 securing screws pass through the ring and the steering and screw into the boss.

If I could get the scanner to work and remember how to post images it would be much simpler.

Richard

[richards]

Oh and more...

The GTA boss part number in my book is given as 105.32.23.520.01 and the TZ part numbers are 105.10.23.520.00/02/03/04 - no 01!

Richard

[classicalfas]

My wheel is a lighter color at 360mm or 14.250" with 4 holes at 12, 10, 8, and 6 mm. On the back is stamped 2 and 8.