IRS torque control

[7ish]

The powers that control certification of the Factory Five kits in New Zealand are unhappy with the rear upper link on the Mustang IRS, as it has been modified from the original Ford design.

They seem to think that the supplied rodend would not be sufficiently strong to counteract the torque reaction as supplied with the ff kit.

Has anyone ever heard of a FF IRS suffering any issues with bending or failure of the top rodend or suspension arm?

Thanks for your comments.

[David Williamson]

You are using the new version IRS based on the 2015 and newer Mustang? It is very strong and I am not aware of any failures. On my Coupe with sticky 315 Michelin Pilot tires and 450 Hp it just spins the tires.
David W

[edwardb]

No issues have been reported on either forum of any type of IRS component failures. Including the component you reference. It's now going onto 8 years since it's been used in hundreds (thousands?) of builds. This includes normal street driving (like me) up to and including numerous dedicated track cars. It's a non-issue. Perhaps a more technical response could be obtained from Factory Five if required.

[J R Jones]

The upper link on an IRS experiences relatively little (acceleration) tension and somewhat more (brake) compression load because it supports a bearing carrier, unlike a live axle that torques in reaction to the pinion/ring gear.
You could look up the loading capacity specs for the rod end size that you have and explain the situation to your authorities. Dynamics and numbers. They will be impressed? maybe
jim

[7ish]

Thanks for the replies. I had no doubts about the design and that is confirmed by the lack of reports about failures.

Hopefully FF will be able to supply the data to the NZ authorities.