Lower A arm ID for F-85

[therobski]

Hi guys just signed on the site. I am currently building a 64 F85 post "bare bones granny car" I have a ton of pictures on this project so far that I will post. The Issue today is please look at the attached pictures of these lower A-Arms. They appear to be UMI's but not sure. My problem is these will not work with my B-spindle/I-ROC 1LE brake upgrade. The lower ball joint will not seat enough to get the crown nut all the way on. I think the taper is different for a B-spindle ball joint, than a A-spindle lower ball joint. Question is if these are indeed UMI control arms can I buy MOOG or whatever B-spindle ball joints and have them pressed in or is the lower control arm shaped different? The upper arms are totally different. Notice the shock hole is routed out to fit the QA-1 shocks. The holes for the shock bolts are now very close to edge of the routed out shock hole-also makes me a little concerned. Thanks.

[killer69]

the B body Ball Joint has a 2" per Foot taper on it, the A Body has a 1.5" per foot taper, they are not compatible. the B body ball joint has a larger od where it is pressed into the arm. there for they will not fit your arms.
you are kind of in a jam.
there is really no easy answer except to change the spindel to a A body spindle.

[therobski]

Hotchkis and maybe others they have the lower control arms for the B-spindle brake upgrade. Just trying to save a grand! That's what I was afraid of!

[shep]

One of the vendors offered a special ball joint, I think it was just a B body joint turned down to fit in the stock A body arm. Might be an option worth looking at.
If you still have the stock spindles an SC&C stage 2+ kit would be better suited. I think you could run LS Camaro rotors on modified drum brake hubs and still use the 1Le calipers. That would improve bump steer and not mess with your turning radius. Do a search for info on the pros and cons of the B-body spindle upgrade on an A body.

[Hotchkis]

Hi guys just signed on the site. I am currently building a 64 F85 post "bare bones granny car" I have a ton of pictures on this project so far that I will post. The Issue today is please look at the attached pictures of these lower A-Arms. They appear to be UMI's but not sure. My problem is these will not work with my B-spindle/I-ROC 1LE brake upgrade. The lower ball joint will not seat enough to get the crown nut all the way on. I think the taper is different for a B-spindle ball joint, than a A-spindle lower ball joint. Question is if these are indeed UMI control arms can I buy MOOG or whatever B-spindle ball joints and have them pressed in or is the lower control arm shaped different? The upper arms are totally different. Notice the shock hole is routed out to fit the QA-1 shocks. The holes for the shock bolts are now very close to edge of the routed out shock hole-also makes me a little concerned. Thanks.

Therobski – We’re not sure who’s control arms those are, but they are not Hotchkis arms. We can tell by the welds and the “Flying H” isn’t cut in the plate near the ball joint. That lower shock hole is a little scary too. Be careful if you end up using those.





http://www.hotchkis.net/gm_abody_tub...y_spindle.html

[Mr. Anderson]

+1 for the special ball joint. 10 or so years ago my dad and I did the tall spindle conversion on a '64 El Camino using the stock lower arms and Global West upper arms. I remember the lower ball joint being something special but unfortunately cant recall where they came from.

[therobski]

Yes the shock bolt holes are not good. I don't really have a whole lot of $$ in these control arms that nobody can identify. The other concern was initial fitment. Me and another guy struggled with these and got the drivers side to fit, the passenger side the fit is really good at all actually had to take a pipe wrench and bend one of the tabs one the frame a little. These maybe early a arms that the shock hole had to routed out close to the shock bolt holes. Who else besides Hotckis has lower A-arms with the tall Body F body ball joints? Some pictures of the build. I need to start a thread on the build.

[therobski]

Dam wine, the pass side fit was not good at all.