I may make my own rear upper control arms someday.

I need input from you guys on to what loads are seen by these arms. Let’s say a car has 500 ft*lb or torque, and the bunny ear is .5 ft away from ring gear center. That is 500 ft*lbs/.5ft = 1000 lbs of force / 2 control arms = 500 lb compression/tension for each arm. I think compression is more critical.

during accelleration, only tension occurs on the uppers. Compression occurs in braking and cornering.

I agree, compression is more critical for strength (in tension, they could just as well be made out of rope :D )

The highest compression loads will occur while cornering, but I'm not smart enough to figure out what that will be. You may want to search around on www.corner-carvers.com for similar numbers posted for fox-body mustangs. Read their rules before attempting to post there though... they're real strict on enforcing them. :yes:

Also figure loads may spike during cornering on uneven surfaces, or if you spin off-track :D so definitely over-build them. :yes:

Thanks for the reply.

I guess I can use the stock ones as a baseline. I can 3d model rear end housing side of the stock arm (I believe .090” THK u channel), and run a FEA with mild steel properties in tension/compression. I’ll adjust the load until I see yield.

I’ll also check out the site you mentioned.

Factor of safety is your friend in this case. There is no reason build the upper links to a minimum strength.

Ryan

Factor of safety is your friend in this case. There is no reason build the upper links to a minimum strength.

Ryan

Agreed. I want to try and use mild steel for the adjuster, and want to find out when it will fail.

Calculated some good info located in this thread:

http://www.chevelles.com/forums/showthread.php?t=257851&page=3