OK, I have searched for this and can't find the answer.....

I'll shortly be buying an Indy with some standard Sierra uprights and some lovely Cortina uprights with great brakes.
I much prefer the Cortina uprights......

A few times people have discussed using Cortina Uprights on an Indy, but the answer has either been:
- No, just use Sierra
- Yes, you could, but you'd need to remake wishbones etc, geometry's different, etc. But I've never seen this go any further.
- (OR, another option, you can now buy the new HiSpec ally Sierra replacement uprights, but that will cost £££)

So, my 2 requests for help from the massive power of the forum are:

- Has this actually been done before? Any pics/build diaries/descriptions of how it was done?
Or
- If not, why not? It seems fairly simple to me. Make a new top wishbone, about 20mm longer (I'll do more precise measurements later, of course) to adjust for less KPI on the Cortina, and a little more rearward position on the outer ball joint to give more castor for self-centring (a known Indy problem). Maybe if a thread is different i'd need different BJs/TREs, but that's no biggy, I can't see any other issue.

If I'm remaking, I can also adjust for any other geometry differences which come up, using some brainpower, string, a tape, and more knowledge from the forum!

Am I missing something?

Thanks
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I helped a mate of mine to do this exact conversion on an Indy R when he purchased my Cortina uprights after I upgraded to Ally versions.

All we had to do, was do exactly what you think, add ~20mm to the length of the top wishbone. He actually had MK make new wishbones. The rest all fitted together with no problems.

I'll see if I can get him to send a picture but its not a difficult job.

Thanks Callan,
Glad I'm not going mad! I'd love to see a photo.

I've also replied to your email on the other question, that's for another option i'm considering, but if this one works it would be great.

Cheers
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