Tubular Control Arms.

[SA E30]

Version 1.0 in Steel.

Later we will get them machined out of ally (pricey).

[Aptyp]

what did all ball joints cost you? and which kind did you get? Going to post up some specs? and fitment?

[SA E30]

Not sure if the Rod end price will really be relevant to you guys as I'm in South Africa.

I used the Early Tubular DTM arms and Gustaves arms as a base line. They are slightly different to dimensions to what someone with a e30 strut would use (We are using e36 328i Group N struts)

Still have to buy the new rod ends and spherical bearing, the ones in there are not the correct size, with the exception of the rear one.

I'll post more pictures tomorrow.

[Hick]

i need those.

once i make this current DD into an autocross/track car only im going to look into making a set.

those heim joints, mainly the inner, look weak. whats the rating on that one?

[87e30]

What is the benefit of this? Is it simply weight?

[Hick]

adjustments. more camber

[SA E30]

i need those.

once i make this current DD into an autocross/track car only im going to look into making a set.

those heim joints, mainly the inner, look weak. whats the rating on that one?

Still have to buy the new rod ends and spherical bearing, the ones in there are not the correct size, with the exception of the rear one.

[Hick]

Oh sorry, i passed over that.

if you make a detailed write up with sizes, part numbers, and what not then i wil love you forever!

[blueapplesoda]

I've also been wanting to do this for a while and just haven't had the time.

What size rod ends are you planning on using? I searched some, and so far I've only come up with a few rod ends that seem like they might work, but I'm not diggin the quality.

[xLibelle]

i like this! nicely executed for a first-timer!

BUT.... i highly advise against track implementing them with the two holes drilled in the ring of the lollipop. A better design would be to leave them as designed and build a "bolt-on" much like Gustave has on his site.

I'm no structural engineer, but i can see a situation of concern when it presents its self.

[mazur]

What is the benefit of this? Is it simply weight?

Camber, like already mentioned, but caster as well.

And if you make it mount higher up on the subframe you can improve roll center, which I would be most concerned about when making custom arms.

[StreuB1]

[StreuB1]

The mods to the lollipops are fine as long asthey are sleeved with sufficient wall thickness.....which it looks like they are.

Other concerns are the lack of rosettes on the threaded tube ends. Very very important to do this. Drill a 1/4" hole in the tube 3/4 of the tube diameter from the tubing end and perform two rosettes 180° opposite eachother. This puts an extra mergin of safety into the joint. One radial weld in tension/compression and the two rosettes in shear.

Also the strut balljoint connection should be gussetted in all 4 planes. One radial weld is not sufficient to handle the forces put on that ball joint sleeve. You need always engineer into a system several lines of safety incase one fails.

Also is the other tube sleeved where it attaches between the two plates? Since it looks like you sleeved the lollipop, Id assume you sleeved this penetration also. Just wanted to ask.

Main areas to address are the lack of gussets on the ball sleeve and the lack of rosettes.

[xLibelle]

the lollipops are carrying an incredible amount of weight under braking, i'm highly against compromising the original structural integrity with cuts and welds.

This should be the only way to utilize the OEM lollipops

Acutally, i'm not happy with the wall thickness of the adapter ring on the front side. Should be thicker and a relief angle implimented or additional brace support on the front.

Streub, what do you think of this build?

http://www.e30m3project.com/e30m3performance/installs/installs-3/control_arms/index.htm

[SA E30]

Thanks for the input guys.

I should also add that these arms were designed by the head Race engineer for Nissan Motorsport South Africa, and welded by their head fabricator (aka the guy that welds the chassis for the Nissans that take part in Dakar).

I don't think that there is a need for the extra gusseting on the bearing carrier or the need for plug welds. The reason I say this is these arms are designed with an inherent weakness so if there is a substantial hit, the suspension will break and not stay fixed, in turn not ripping the chassis to pieces.

The lollipop penetrations are sleeved on both ends



The Lollipop pickup I'm using a 3/8th's Rod end with 1/2inch UNF

The inner pickup is using 1/2 inch rod end also with 1/2inch UNF

The spherical bearing is 1 and 3/8's.

All the bearings and rod ends are from Aurora and are aerospace spec.



Sorry about the bad pictures my camera wasn't co operating with me.