Alfa Romeo Forums banner
1 - 8 of 8 Posts

·
Registered
1969 1750 Spider Veloce (Euro)
Joined
·
88 Posts
Discussion Starter · #1 ·
I ordered a front suspension ball joint kit from Classic Alfa (UK) for my '69 1750 Spider (euro). It's a 105 series kit that comes with a pair of lower ball joints, castor arm ball joints, and upper control arms. After seeing that the wheel camber was much too positive, we discovered that the replacement upper control arms were about 5mm longer than the original ones (see pic below). Classic Alfa was very puzzled. Does anyone have a logical explanation for why my car's arms are shorter than what was expected?


1695365
 

·
Registered
Joined
·
1,856 Posts
Interesting find. Do you know if the originals are original to the car or where they also changed at some point?
Looks like the difference is where i've circled in red.
Its always a good idea to go with adjustable ones so that you can dial in the front end.

IMG_7677_LI.jpg
 

·
Super Moderator
Joined
·
12,071 Posts
I don't know the right answer to your question. But you asked for a "logical explanation", so here are two possibilities:

- That's just the tolerance that aftermarket parts are built to today. Were both new arms equally long?

- If the answer to GTA ALFA's first question is "yes" - e.g., the old arms were original to the car - then is it possible that early 105's had slightly different front end geometry than later cars? And that the control arms available today are only correct for later 105's? (Though, if this were the case, you'd think CA would know it).

Either way, as GTA ALFA suggests, adjustable arms may be in your future. Which is unfortunate, because the adjusting hardware on those things will interfere with the "box" the inner ends fit into if much caster is dialed in. The solution I've used for this is to install the inner bushing so it is biased rearward, so the arm originates toward the front of the "box".
 

·
But Mad North-Northwest
Joined
·
12,068 Posts
Dunno what to tell you. But like Anthony said, if you're going to replace them you should go with the adjustable arms.

Classic Alfa also recommends replacing the two bushings on that arm with poly, and I've found that to be good advice.
 
  • Like
Reactions: Dr. Lo

·
Registered
Joined
·
298 Posts
why do you assume the ones on your car are wrong? since alignment was good w them, i would assume they were the correct ones. fwiw, agree on the adjustables. can dial in or even crank in a little neg camber if want.
 

·
Premium Member
Joined
·
453 Posts
I thought I read somewhere on the BB that there is an early- to late-model difference in control arm length, and that only one length (presumably late-model) is available from the aftermarket. So likely nothing wrong with the original arms, and the answer is what everyone suggests, use the adjustable ones. I haven't run into the problem that Alfajay reports, but also haven't messed with the caster much.
 

·
Registered
1969 1750 Spider Veloce (Euro)
Joined
·
88 Posts
Discussion Starter · #7 ·
Interesting find. Do you know if the originals are original to the car or where they also changed at some point?
Looks like the difference is where i've circled in red.
Its always a good idea to go with adjustable ones so that you can dial in the front end.

View attachment 1695371
I’m quite sure that the old ones were original to the car. Thanks for suggesting the adjustable arms.
 

·
Registered
1969 1750 Spider Veloce (Euro)
Joined
·
88 Posts
Discussion Starter · #8 ·
I don't know the right answer to your question. But you asked for a "logical explanation", so here are two possibilities:

- That's just the tolerance that aftermarket parts are built to today. Were both new arms equally long?

- If the answer to GTA ALFA's first question is "yes" - e.g., the old arms were original to the car - then is it possible that early 105's had slightly different front end geometry than later cars? And that the control arms available today are only correct for later 105's? (Though, if this were the case, you'd think CA would know it).

Either way, as GTA ALFA suggests, adjustable arms may be in your future. Which is unfortunate, because the adjusting hardware on those things will interfere with the "box" the inner ends fit into if much caster is dialed in. The solution I've used for this is to install the inner bushing so it is biased rearward, so the arm originates toward the front of the "box".
Great info, thanks! Yes, both of the new ones are equal in length.
 
1 - 8 of 8 Posts
Top