Driving Impressions: Lower Stress Bar

[Bobiam]

A QUESTION for those of you that have installed an "ernie bar". I was thinking of using 7/8 hexagonal aluminum stock. So the overall "corner to corner" diameter is about 1.039". The hexagonal shape gives me the advantage of having nice flats and heavier 7/8" diameter at the mounting points.
Does anyone anticipate a problem installing this size material??? Or should I reduce the size to 3/4" hex?

Thanks, Bob

[Kirk]

Here are some quick pics of my new and improved lower stress bars (all three). The large main bar ties the left and right sides of the car together. The two smaller bars then tie the left and right sides to the support in the middle/rear of the car, thus triangulating the three bars together and giving extra stiffness.

Basically I've been running with a homemade setup like this for a couple months and really appreciate the improvement. Now I've taken it a step further by upgrading to light weight and stronger racing components. I'm going to take these parts to work tomorrow and weigh them before I install them. But they're really very light weight. The rod ends or heim joints are three piece (not the cheap two piece) units made out of hard anodized aluminum. Each heim joint is rated to hold over 4,000 lbs! The bars and locking nuts are all aluminum too. Man this is a slick setup. I can't wait to get them on the car!

Kirk

[Kirk]

A closer look at the heim joints.

[insite]

Originally Posted by Kirk

A closer look at the heim joints.

kirk -

awhile back, i designed and built some sway bar links. i tested the rod ends in your pictures. they are rated at 4,000lb radial and 1,500lb axial. wanna know what they tested at? 800lb radial and 240 lb axial. i'd remove them from your car; they are garbage.

[Kirk]

Originally Posted by insite

kirk -

awhile back, i designed and built some sway bar links. i tested the rod ends in your pictures. they are rated at 4,000lb radial and 1,500lb axial. wanna know what they tested at? 800lb radial and 240 lb axial. i'd remove them from your car; they are garbage.

Yeah I got some conical spacers to try these heim joints out as sway bar drop links. One of the seals on a rear drop link on my car is bad and I want to replace it with something using heim joints. After looking at the parts I would agree that they're probably not up to the task as a sway bar link. I think you need something fairly robust for that application, probably made of steel. At least I know what size to get now for the spacers and heim joints. I'll have to see what parts I can find.

For the stress bars though they won't be exposed to as much of a dynamic load as the sway bar drop links. Their role is to support and reinforce the thin sheet metal stress plate that Porsche puts in there. So I think that in this role they will be more than sufficient, especially in use on the smaller, secondary bars. Either way, they can't hurt and can only really help in this application!

I'll know more in a couple weeks. I weighed them this morning - 5 oz for the side bars and 6.8 oz for the main bar - super light weight! I'll get them installed soon and then put the car through its paces and see how they hold up.

Kirk

[insite]

axial load is what i'd worry about. if the car twists, the inner race will pop out of the heim joint fairly easily.

PM me if you need race duty drop links; i still have a set on hand.

[Kirk]

Originally Posted by insite

axial load is what i'd worry about. if the car twists, the inner race will pop out of the heim joint fairly easily.

PM me if you need race duty drop links; i still have a set on hand.

Sent ya a PM.

Yeah, I can see your concern. I'll give these heim joints a try and see how they hold up. I'm getting new wheels next Monday with 20 mm wider rubber and super sticky Falken 615 tires. Once I get those on the car I'm SURE the new stress bars are going to get a real workout. I know I'm going to be having some fun and pushing the car to the limit.

I think the aluminum heim joints like this are perfect though for the side bars. I may just need to go to a steel heim joint and hollow steel tube for the main bar.

[chaudanova]

Originally Posted by Kirk

Here are some quick pics of my new and improved lower stress bars (all three). The large main bar ties the left and right sides of the car together. The two smaller bars then tie the left and right sides to the support in the middle/rear of the car, thus triangulating the three bars together and giving extra stiffness.

Basically I've been running with a homemade setup like this for a couple months and really appreciate the improvement. Now I've taken it a step further by upgrading to light weight and stronger racing components. I'm going to take these parts to work tomorrow and weigh them before I install them. But they're really very light weight. The rod ends or heim joints are three piece (not the cheap two piece) units made out of hard anodized aluminum. Each heim joint is rated to hold over 4,000 lbs! The bars and locking nuts are all aluminum too. Man this is a slick setup. I can't wait to get them on the car!

Kirk

WOW, Looks AWESOME Kirk.... you are tha man!