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Discussion Starter #1
looking for a picture that shows a factory spindle from a 65 FB next to a larger spindle from a Granada. i want to see the two compared side by side. thanks for any pics.
 

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This is a side-by side of the '65 (top) and the '71 drum brake spindle. My understanding is that the taper geometry as well as the bearings are common between the '71 and the Granada.

Someone please correct me if I'm wrong.

http://forums.vintage-mustang.com/forums/photopost486/data/500/37250spindle_comparison.JPG
 

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Nice picture, but it is slightly misleading. The outside diameters of the bearings on those two spindles are the same. Ford only changed the inside diameter - i.e., the thickness of the spindle.

John Harvey
 

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I think the optical illusion is because one spindle is closer to the camera than the other.

You're right, that the OD of the bearings are the same. I was able to quickly mount my rotors (using the same outer races) on the '71 spindles using the bearings from the '71 donor cars. With that setup, the spindle nuts didn't quite go far enough in on the '71 spindle. The cotter pin wouldn't go through. I assume that I'll have to replace the outer races to get everything to line up.

The ID of the bearings are quite different though.
 

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Discussion Starter #5
nice picture. thanks for the information. for some reason i thought the spindle swap was far more involved.
 

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Just curious - has anyone on here ever personally broken a 65/66 V8 spindle??? ;) No "my brother's uncle's cousin's dog-groomer" stories.... :winkgrin:

I know that "some is good, more is better, and too much is just enough", but is the (unneeded?) extra beef really necessary, especially considering the geometry tradeoff? :: I'm sure for a strictly opentrack car :track:, it could be justified, but how many billion street miles have been logged on stock spindles?
 

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You're right, I haven't personally seen any broken.

Given what's available and that the only trade-off is bumpsteer which can be fixed (stay tuned for results on the Baer Tracker kit with the '71 spindle), I see no reason to put a couple of hundred bucks between yourself (and your family) and added safety.

The ball joint geometry is identical, the tie rod pickup point is slightly higher on the later spindles and the '70 outer tie rod bolts right in. It's pretty straight forward.

I figure that if Ford saw reason to beef the spindle up as the weight creeped in the later years, that's a pretty good indication. Compound that with our current race tires which generate MUCH more grip than 60's street tires and things just get more and more marginal.
 

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Discussion Starter #10
i agree with your point, which is something i wonder about too: 'how many have really ever broken?'

but i think the primary reason behind the big spindle swap is to improve braking (by reducing or eliminating spindle FLEX), not prevent complete spindle failure.

in my opentrack experience, i think i am getting enough spindle flex that the front brake pads are moved away fronm the rotor and thus not sitting flush. this translates into a soft pedal (not fade) because most of the pedal travel is being used to set the pad against the rotor leaving pedal towards the bottom of its travel before it firms up. i currently run an SSBC front disc with 12" rotors.

at present i counter this problem by tapping the brake pedal twice (to set the pads flush) before i hit my braking zone and really stomp on them. i've heard similar complaints.
 

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"Given what's available and that the only trade-off is bumpsteer. . . ."

This isn't the only trade-off. If you use Global West arms and big tires you can get serious binding issues (because of the changed angles). See GT350clone's site for his personal experiences with the swap spindles.

John Harvey
 

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http://www.sunflower.com/~vervaecke/granada.htm

http://www.sunflower.com/~vervaecke/our_story.htm

Please identify which "angles" he stated are changed when you change spindles. I read through both pages I could find about his story and the only physical dimension that I found him quote as being different was the steering arm on the spindle.

From the sounds of it, a lot of suspension parts were changed only to find out that the car had different bumpsteer characteristics that we servely evident under different driving conditions.

From my measurements of two spindles ('65 and '71), the upper and lower ball joint locations are identical. I can't speak from personal experience about the Granada part, but the consensus on c-c.com and the gentlemen that's re-casting Granada spindles is that the Granada upper and lower ball joint locations match both of the parts that I measured.

Once the steering arm changes you have to realign the car and bumpsteer will probably change as well. No big deal. I'll be testing the Baer Tracker kit soon on the '71 spindle and will report my results in the bumpsteer thread here. Opentracker's initial tests on his car show that bumpsteer can be eliminated with the Granada spindle.
 

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The steering arm angle is the one that matters in this case. When compared to the center line of the spindle and the fore and aft center line the position of the tierod attachment point is in a different spot. Hence the characteristics of the rate at which the car turns its wheels changes. Also the Ackerman angle is different as well. Most people don't have a problem but occassionally the problems are severe.

I've never heard of anyone breaking a 65/67 spindle, but I guess flex could theoretically be a problem. So I guess you are in a difficult spot. All I'm saying is that there may be more difficulties with the swap than you are planning on, for your sake I hope there isn't.

Best of luck and tell us how it all turns out. More data points from actual experience would be good to have.

John Harvey
 
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