1303 control arms

For road racing, autocrossing, or just taking that curve in style. Oh yea, and stopping!
Post Reply
H2OSB
Posts: 472
Joined: Mon Aug 21, 2000 2:01 am

1303 control arms

Post by H2OSB » Sun Jun 25, 2017 11:32 pm

Greetings all--

I'm sitting here looking at my pretty pair of black powder coated, late LCAs I plan to install on my '74 Super. I'm a bit concerned because my car is lowered two and a half inches and thus the control arms sit very close to horizontal. I would love to find a set of extended ball joints to get the control arms pointing down a bit, however, the only person I've ever seen with a pair (in a thread on STF) has yet to respond to my PM. That said, as I sat looking at my control arms it dawned on me they LOOK as though they could be flipped over to give a LITTLE more downward angle. The ring where the ball joint is pressed in sits so the top of the ring is about 1/4 inch above mid-line of the arm, and the ring itself is 3/4 inch tall. Therefore, if the arm were flipped, the gain would be about 12 or 13mm. I don't see how safety would be compromised, however, I'm no automotive engineer, so I don't have a clue for certain. Has anyone ever tried this?

H2OSB

H2OSB
Posts: 472
Joined: Mon Aug 21, 2000 2:01 am

Re: 1303 control arms

Post by H2OSB » Mon Jun 26, 2017 1:34 am

Small follow-up:

I began scanning google images to see if I could find anything about flipping 1303 control arms. I came across a thread on a page I was unfamiliar with. A guy, who was an off-roader, out of boredom, decided to build a German Look Super. Through out the thread, he posted pictures of his progress. In one part, he describes replacing his drum brakes with a disc brake kit from Topline. In one picture I spotted he had his control arms upside down. He did that brake conversion in 2011, and he was still adding to his build thread in 2015. I'm going to assume, after 4 years, with no mention of an issue with the suspension, the flipped control arms worked out fine.

I think I'll give it a go when I install my new LCAs.

H2OSB

P.S. Upon looking closer, I don't believe the guy had his control arms upside down. They just looked as if there were made with the ball joint cup more up than is usual on the stamped steel later control arms. Alas, back to wondering if it's ok to flip them

User avatar
Piledriver
Moderator
Posts: 21786
Joined: Sat Feb 16, 2002 3:01 am
Location: Van Alstyne, Texas

Re: 1303 control arms

Post by Piledriver » Mon Jun 26, 2017 2:41 am

The late cars have less of an issue IIRC.

I flipped early forged arms and welded new ends on...
I extended them so the camber adjustment was in the middle at 0 at ride height, using 944 struts.
If you are using the Mk1 Golf Topline struts, the dimension may differ.
Need the pictures again?

Again, Coleman racing could make these for you reasonably, with a heim eye in the middle for a trail link if desired.
Then you can put the sway bar wherever it doesn't hit.

All you need is a decent drawing with dimensions.
...And of course, some money.
I, for one, regularly embrace our new robot overlords, as I am the guy fixing the robots...

User avatar
ChadH
Posts: 183
Joined: Wed Mar 30, 2016 6:55 pm

Re: 1303 control arms

Post by ChadH » Mon Jun 26, 2017 10:35 am

Just a random BS idea...Instead of looking at the outside of the control arms - look at the inside. Add a second set of inner control arm mounts above the centerline of the sheet metal pan. Obviously, you'd want to really over-engineer these, and make sure there were very good welds.

Think about an R/C car, with multiple locations to mount suspension ball joints for tuning.

FWIW - This would make it really quick and easy to change from the lower mounts to the upper mounts. You could quickly see if there are noticeable handling improvements. Then report your findings back to me before I head down this rabbit hole. :P

H2OSB
Posts: 472
Joined: Mon Aug 21, 2000 2:01 am

Re: 1303 control arms

Post by H2OSB » Mon Jun 26, 2017 12:37 pm

It's not a bad idea. I've always felt inner control arm mounts are incredibly vulnerable with even a very moderate drop. I have a couple ideas I may look at.

H2OSB

H2OSB
Posts: 472
Joined: Mon Aug 21, 2000 2:01 am

Re: 1303 control arms

Post by H2OSB » Mon Jun 26, 2017 12:37 pm

Double post
Last edited by H2OSB on Mon Jun 26, 2017 3:34 pm, edited 1 time in total.

H2OSB
Posts: 472
Joined: Mon Aug 21, 2000 2:01 am

Re: 1303 control arms

Post by H2OSB » Mon Jun 26, 2017 2:37 pm

It might just be time to seriously consider some kind of narrow A-arm type of arrangement. Something that fixes caster and isolates the sway bar out of the suspension geometry. Going to the effort to change the inner mount or changing to a longer pin on the ball joints (sure would love to do that) is really just a bandage for a suspension design created to be cheap (well, and give more trunk space) and not ever to be used for higher performance.

For now, I'm just going to use my pretty, black LCAs as they are.

H2OSB

User avatar
ChadH
Posts: 183
Joined: Wed Mar 30, 2016 6:55 pm

Re: 1303 control arms

Post by ChadH » Tue Jun 27, 2017 1:29 pm

You could just grab a solid NA Miata for a few thousand and throw good tires on it - Boom done! :P

..I'm still wondering why I haven't done this, other than a weird affinity for old VW's, and an antisocial motivation to be different. 8)

H2OSB
Posts: 472
Joined: Mon Aug 21, 2000 2:01 am

Re: 1303 control arms

Post by H2OSB » Tue Jun 27, 2017 3:40 pm

double post. sheesh
Last edited by H2OSB on Wed Jun 28, 2017 5:17 pm, edited 1 time in total.

H2OSB
Posts: 472
Joined: Mon Aug 21, 2000 2:01 am

Re: 1303 control arms

Post by H2OSB » Tue Jun 27, 2017 3:40 pm

For me, it's a flat out desire to autocross a curved window Super Beetle. I want to build the car so it's fun and predictable. I have no illusions it will be competitive. If I wanted to win, I'd buy a Miata, like you said. Hell, I could autocross my daily driver...an '06 Subaru Legacy GT. BTDT.

H2OSB
Last edited by H2OSB on Tue Jun 27, 2017 6:14 pm, edited 1 time in total.

User avatar
ChadH
Posts: 183
Joined: Wed Mar 30, 2016 6:55 pm

Re: 1303 control arms

Post by ChadH » Tue Jun 27, 2017 5:49 pm

Same thing here.

I know when talking about other racers in our club, if someone says "..you know, that guy with the red Miata.." I draw a blank. However, I do know exactly who drives the Datsun 510, the '82 Toyota Starlet, the Caterham, the POS primer black BMW E30, etc.

TZepeSH
Posts: 169
Joined: Wed Nov 03, 2004 1:55 am

Re: 1303 control arms

Post by TZepeSH » Wed Jun 28, 2017 3:02 am

Why do the control arms need to be inclined, and it is not good to have them horizontal? My 1303 is also lowered ~2.5" with Topline struts, and never got a problem.

User avatar
Piledriver
Moderator
Posts: 21786
Joined: Sat Feb 16, 2002 3:01 am
Location: Van Alstyne, Texas

Re: 1303 control arms

Post by Piledriver » Wed Jun 28, 2017 3:32 am

It probably won't make a measurable difference unless you are competing at the highest levels of pro solo or such...
There are also probably a hundred things you can do that would be more effective.
#1 for many people would be reducing the "payload" by 20-30 pounds. :twisted:
Keeping the weight off is always the hard part, most suffer from liking food.
I, for one, regularly embrace our new robot overlords, as I am the guy fixing the robots...

H2OSB
Posts: 472
Joined: Mon Aug 21, 2000 2:01 am

Re: 1303 control arms

Post by H2OSB » Wed Jun 28, 2017 7:57 am

As the control arms and tie rods get closer to horizontal their arcs change relative to each other creating bump steer at some steering angles. The downward factory angle was designed to limit this.

H2OSB

Post Reply