Knuckle Risers

[conedriver]

Group,

I asked a question in the GTAM thread about knuckle risers. Specifically, did the 105 series cars (especially Spiders) eventually incorporate the geometry from these parts into the basic stock suspension and, if so, when?.

No less an authority then the ever popular Papajam (Jim Neil) posted the reply below so I thought to try for a wider response by starting a new thread. Thanks for any information.

"After searching around a bit, the only model I found that Alfa fitted what they called a 'joint attachment', part number 105.32.21.118.00, as standard equipment was the GTA. It was also offered as an option on the GTA 1300 Junior. Note the 105.32 p/n designation, the unofficial type number of the GTA (the official type # is 105.02/A).
The 11/71 and 2/77 issues of the Performance Options Catalog list an Autodelta 'knuckle riser extension', 105.51.21.118.99, for all 105 series cars which, because of the 105.51 p/n, leads me to believe that these extensions first appeared on the 105.51 GTAm. In addition, the steering knuckles listed in these catalogs have different part numbers than those knuckles listed in the parts books for the 'regular' production cars.
All this means though is that later production road cars didn't have knuckle risers. It does not rule out, however, the possibility that Alfa incorporated this suspension geometry for the later cars in the form of taller steering knuckles.

Quite the long winded response which boils down to I haven't got a clue"

the later 2000 105 and 115 cars were advertised with GTA inspired suspensions, but that may just apply to the addition of the Limited Slip system, is there a difference in part numbers for the first of the 105 and the last?

[conedriver]

Hi Randy,

You have a good point. After I sent the original query, I realized that the height of a knuckle riser is around 2 in. so comparing heights of old vs. newer spindles should provide the answer. I have access to a Duetto, GTV-4, 1976 Spider and 1991 Spider so maybe a simple measurement will answer my question. Or, maybe Jim Neil will be inspired to check the part numbers for spindles during the time span.

Quote:

Originally Posted by alfa of-corse the later 2000 105 and 115 cars were advertised with GTA inspired suspensions, but that may just apply to the addition of the Limited Slip system, is there a difference in part numbers for the first of the 105 and the last?

forgot to mention that the 1750 cars have different alignment specs, but that could be a result of the switch from 15 to 14 wheels, but the only difference is in camber 50 in the 1600 and 20 in the 1750 and 2000. I have no idea if and when a change was made, but Alfa does have a history of incorporating racing tech into street cars, particullary during the 60's and early 70's, I wouldn't be surprised if the 1750 suspensions changes were a result of things learned on factory race cars.

[ossodiseppia]

Mike Valant put knuckle risers on his Giulia Super. Read here.

[Bill77]

Thanks for the link to Mike Valant's website. There is a lot of good information there, especially regarding engine rebuilds.

[papajam]

Somehow I just knew I should have researched the knuckles for that other post.

The short of it is, except for the GTA & GTA Jr, the 1300/1600 steering knuckles have different part numbers than the 1750/2000 knuckles. The only running production change in the knuckles that I could find was in mid 1967 when the 1300 engined Giulia TI, Giulia Super & the GT Jr. switched from the 105.14.21.010.00 RH and 105.14.21.011.00 LH knuckles to the knuckles that all the other production 105 cars had been using at that time; 105.14.21.010.03 RH and 105.14.21.011.03 LH. These knuckles were then used on 1300 & 1600cc 105s thru at least 1972.
The steering knuckles for the 1750 & 2000 105/115 cars, 105.41.21.010.01 (60516727) RH and 105.41.21.011.01 (60516728) LH, at least for the US version cars, remained the same from 1969 thru 1990, the latest year for which I have part numbers.
The GTA used 105.32.21.010.01 and 105.32.21.011.00 steering knuckles.
The Alfettas (GTV4) have different knuckles altogether and carry a 11600 part number.

The differences between the 1300/1600 and 1750/2000 knuckles could be a few things including a possible difference in overall height; spindle length/diameter, caliper attachment, kingpin inclination and even the backingplate attachments to name a few off the top of my head. I'd have to research this though. The mention of 15" and 14" wheel diameters is a good one and in fact, the Performance Options Cat. lists 105.48.21.100.25 LH and 105.48.21.100.26 RH knuckles for use on cars that have 13" wheels. However, the Spider Junior 1.3/1.6, which had either a 155x15 or 165x14 tire/wheel offering, used the same knuckles with either wheel diameter.

[ossodiseppia]

Quote:

Originally Posted by papajam Somehow I just knew I should have researched the knuckles for that other post.

[George Willet]

What I have found, (after making my own knuckle risers and installing them on '69 spindles on a race car, what an error!) is that the knuckle risers were only for the spindles that had the bolt on brake caliper adapter. This, in the USA, would be the 1965 105 series spindles. These (1965 105) spindles are one inch shorter in the distance from the spindle to the upper ball joint mount. The lower dimension from the spindle to the lower ball joint mount is the same for 105 and 115 spindles. The riser raised the ball joint on the 1965 spindle to the same height as later production spindles. So Alfa incorporated the design change/improvement on the production line. All that clear?

[ossodiseppia]

Quote:

Originally Posted by George Willet bolt on brake caliper adapter.

[conedriver]

Thanks George,

You verified that all U.S.105/115 series Alfas after 1965 have the dimension of the add-on knuckle riser included in the stock spindle height.

Quote:

Originally Posted by George Willet What I have found, (after making my own knuckle risers and installing them on '69 spindles on a race car, what an error!) is that the knuckle risers were only for the spindles that had the bolt on brake caliper adapter. This, in the USA, would be the 1965 105 series spindles. These (1965 105) spindles are one inch shorter in the distance from the spindle to the upper ball joint mount. The lower dimension from the spindle to the lower ball joint mount is the same for 105 and 115 spindles. The riser raised the ball joint on the 1965 spindle to the same height as later production spindles. So Alfa incorporated the design change/improvement on the production line. All that clear?

[italcarguy]

Just came across this thread. Are you guys aware that there are two different size knuckle risers? Autodelta made one size and then when the spindle got bigger, they made smaller ones. Which ones are you guys using on which spindles?

[david rivkin]

As I remember when restoring my GTA and then later when converting to ATE brakes is that the knuckle risers were used on cars with the Dunlop brakes. The uprights for the ATE calipers included the height addition of the riser. Today, the Dunlops are packed away, with the risers, in my basement. So if you have ATE brakes spend the money on poly bushings and heim joints.

David
66 GTA
81 GTV6

[Markus N.]

Hello
I have then as a replica
They are better as the originals
I testet them on the two most famous racetracks of the world(Nürburgring nordschleife and Spa-Francorchamps).Both racetracks are 150km far away from my home.
I dont know how to send a pikture in this forum.
If you see them please send me a mail

markusniestrath@aol.com
Sorry for my bad english

Best regards
Markus N.

[Max Banks]

Has anyone ever seen the GTA top arms with extra long pins on the outer ball joint (about 2" longer than standard), I found a set here and wondered if anyone else had ever seen them!? I guess it was an alternative to knuckle risers?