Mark 1 Cortina Steerng vs Mustang

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Lance54
Posts: 35
Joined: Tue Oct 10, 2017 11:36 am

Mark 1 Cortina Steerng vs Mustang

Post by Lance54 »

Having just fully reconditioned the steering in my Mark 1 Cortina I'm now aware of just how similar it is to a 1965 Mustang....

Image

But for the shape of the cross member this photo could be a Cortina.

So many joints in this design. A Rack and Pinion would have been so much simpler.
Bob_S
Posts: 407
Joined: Fri Nov 27, 2009 8:22 pm
Location: Michigan, USA

Post by Bob_S »

Hi Lance
Rack and pinion would have been simpler but most likely it would have been more expensive.

Developing a new system can be quit costly, nothing off the shelf to borrow from or modified. Modifying an existing part cost less than a new part. The first program to use the new system/part pays the cost for the development and tooling even if there is a followup program that will use the same part.


Example 1:
Say that the tooling will support 200,000 parts per year but XYZ program only needs 100,000 parts. ABC program will launch 6 month after program XYZ and program ABC needs 50,000 parts. Program XYZ pays for 100% of the tooling and development while program ABC pays nothing.

Program XYZ can't afford the tooling and development cost so it ends up using modified or carryover parts already in production.

Example 2:
Say that the tooling will support 110,000 parts per year but XYZ program only needs 100,000 parts. ABC program will launch 6 month after program XYZ and program ABC needs 50,000 parts. Program XYZ pays for 100% of the tooling for the 110,000 and development of the part.
While program ABC pays for the tooling for the incremental 40,000 parts. The tooling for the incremental 40,000 parts cost less because all the tool design, cutting paths etc. have already been designed and the part has passed durability testing. The incremental tooled parts may have to go through some minor durability testing.


I hope this makes sense.

Cheers,
Bob_S
Bob_S
First car 70 Cortina GT
Lance54
Posts: 35
Joined: Tue Oct 10, 2017 11:36 am

Post by Lance54 »

Thanks Bob. Good analysis of how volume is needed to pay for research and tooling.

Still seems odd that rack and pinion was common from the early 50s in sports car but so many sedans kept the steering box and associated linkage. I bet is was a result of engines being moved further forward to enlarge cabin space.

Others like Alfa Romeo, BMW and Datsun all used steering boxes well into the 1970s and beyond.

Clark
Bob_S
Posts: 407
Joined: Fri Nov 27, 2009 8:22 pm
Location: Michigan, USA

Post by Bob_S »

Hi Lance,
It also has to do with efforts. Recirculating ball steering boxes usually had lower efforts VS rack & pinion which are limited by the size of the rack. Back in the day some recirculating ball steering boxes had 4 + turns lock to lock.

I am surprise that the MK2 Cortina did take the rack & pinion from the Taunus 12m P6 since that can out in 1966. But then again Ford of England and Ford of Germany didn't get along.
Bob_S
First car 70 Cortina GT
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