Frankenarms Installed Yesterday

[sportfan]

To save weight and have replaceable ball joints and bushings I modified my stamped lower control arms on my 13' Sport. I welded steel braces on the underside to make them stronger. I had to bore out the bushing bore on the rear and weld a steel sleeve in to accept new Powerflex purple bushings. Then I had to bore out the ball joint bore so I could press in new NAPA ball joints. Before I installed the new parts I had them powder coated. Now I need alignment done. I had a transmission seal leak . So while the car was down I replaced the seals and wheel bearings also. With so many different postings on the axle nut torque , I called SKF and talked to their automotive engineer . He said the 229 ft. pds. is correct. One note on the wheel bearings is they can be installed backwards. If they are your antilock brakes won't work. The seal on one side of the bearings has magnets in it that the sensor in the knuckle reads wheel speed from.Frankenarms (5).jpgFrankenarms (1).jpg

[Fiat88]

Nice work! I wish something like this was available from the aftermarket, especially like the idea of replaceable ball joints. After having both ball joints fail at 30,000 and issues with superseded parts costing me $1000 for each side, I have anxiety.

[sportfan]

I've read that ball joint failure is quite common with Fiats. I wonder if it is more commom with the cars with the stamped steel control arms or the cars with the cast control arms. I also wonder if the failures are the control arms or ball joints. I found cracks in my control arms that were near the rear bushing bores. So I guess its possible that they could be around the area where the ball joints are pressed in also.control arm crack (2).jpgcontrol arm crack (3).jpg

[Hermiabarth]

Nice work! I wish something like this was available from the aftermarket, especially like the idea of replaceable ball joints. After having both ball joints fail at 30,000 and issues with superseded parts costing me $1000 for each side, I have anxiety.

There are some really nicely designed control arms from DNA racing, made in Italy - See link below. They have replaceable ball joints and are made for the North American Abarth. I don't know if they work for the 500. I have several other DNA chassis braces and they are well made. I would definitely change to these control arms when I need ball joints (or sooner if I go autocrossing).

https://www.dna-racing.it/en/fiat-500-abarth-usa-components/958-dna-racing-front-suspension-arms-kit.html

[Mikeyjm1]

There are some really nicely designed control arms from DNA racing, made in Italy - See link below. They have replaceable ball joints and are made for the North American Abarth. I don't know if they work for the 500. I have several other DNA chassis braces and they are well made. I would definitely change to these control arms when I need ball joints (or sooner if I go autocrossing).

https://www.dna-racing.it/en/fiat-50...-arms-kit.html

Late to the party. He actually tried and just sold off the DNA arms. They didn’t clear his wheels enough and were rubbing.

[Hermiabarth]

Late to the party. He actually tried and just sold off the DNA arms. They didn’t clear his wheels enough and were rubbing.

Yes I recall seeing that. I wonder just what difference there is between the 500 control arm geometry and the Abarth, aside from the stamped vs. cast material.

[sportfan]

DNA (2).jpg

I believe the shape of the cast and stamped control arms are about the same. The picture attached here will show the differences between a stamped control arm and the DNA control arm. We never could figure out why my wheels rubbed and many other sets of these were sold with no problems.

[Hermiabarth]

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I believe the shape of the cast and stamped control arms are about the same. The picture attached here will show the differences between a stamped control arm and the DNA control arm. We never could figure out why my wheels rubbed and many other sets of these were sold with no problems.

Very curious. Is it possible that you got a set of Euro spec arms instead of the North American variant? I am interested because I'm thinking of installing the DNA arms; they seem to be a much better (and lighter) part than the stock cast arm. It's especially good to get rid of unsprung weight.

[sportfan]

All I can say is the vendor I bought them from contacted DNA about the problem . They bolted on and worked fine as long as I didn't turn the steering too far either way, then the wheels rubbed. The oem Abarth are strong but, like you say heavy. I would like to know how much one of them weighs. When I rebuilt my stamped out control arms I added about a pound of metal to each one. I would guess that they are lighter than the cast Abarth control arms. The DNA control arms weight are 5 lbs. 4.9 oz., the stamped out control arms are 4 lbs. 14.8 oz., and my Frankenarms are 6 lbs. 5 oz..