Author Topic: 427 Cobra rear suspension set-up  (Read 1314 times)

427street

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427 Cobra rear suspension set-up
« on: November 05, 2019, 11:26:31 AM »
Can anyone tell me what the static Castor is in the rear suspension upright of the original Cobra 427 IRS.

Thanks for your help.

Cheers
Greg

A-Snake

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Re: 427 Cobra rear suspension set-up
« Reply #1 on: November 06, 2019, 09:10:36 AM »
Can anyone tell me what the static Castor is in the rear suspension upright of the original Cobra 427 IRS.

Thanks for your help.

Cheers
Greg

The suggested rear setup in April 1965 was 1/2 degree negative camber.

427street

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Re: 427 Cobra rear suspension set-up
« Reply #2 on: November 08, 2019, 01:45:28 PM »
Hi A-snake. I have now learned the CASTOR of the rear upright was spec'd at 2 degrees negative (the top of the upright slopes towards the front of the car).

Cheers
Greg

1109RWHP

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Re: 427 Cobra rear suspension set-up
« Reply #3 on: November 08, 2019, 06:42:38 PM »
Caster!

427street

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Re: 427 Cobra rear suspension set-up
« Reply #4 on: November 09, 2019, 03:29:25 PM »
Yup . CASTOR.

When Ford in 1964 used their first computer simulations to design the independent rear suspension on Shelby's 427 Cobra, they were actually able to design in some rear steering and anti squat when the rear suspension went into compression.

This aided in rear stability and straight tracking while under heavy straight line acceleration or accelerating out of turns where a bump might occur.

So at static (rest) or driving in a straight line with no acceleration or bump compression in the rear, the rear upright had a 2 deg negative CASTOR built into it (top of the upright leaning slightly forward).

Under hard acceleration or a bump (compression),  the Upper Control Arm and leading Lower Control Arm links were so designed (with anti dive and some rear steer) as to move the top of the upright rearward and into Positive CASTOR and created some additional toe in on the rear to aid in directional stability.

I think.

It's really a complex rear suspension.

Cheers
Greg


427street

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Re: 427 Cobra rear suspension set-up
« Reply #5 on: November 09, 2019, 03:30:36 PM »
OOPs.

CASTER!

427street

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Re: 427 Cobra rear suspension set-up
« Reply #6 on: November 09, 2019, 05:28:03 PM »
But if you lube it, do you use CASTER OIL or CASTOR OIL???????????

Cheers
Greg