[olddog]

I have no idea what a 427 SO cost back in the day, but it is a little hard to believe it was significantly more than a 426 Hemi back in the day. Maybe quite a bit less. However to assert that independent racers could not afford Ford engines, which would certainly mean they couldn't afford Mopar either, doesn't seem to me to hold water. If this were true, why did independent racer ever race any Cobra's? I also have to ask just how much could have a 427 SO cost if you could buy the entire car new for ~$5K?

I recall watching Nascar races on TV a lot when those engines were raced. I recall a race when the first dozen cars (give or take) alternated between Ford and Mopar. The big block Chevy's seemed to run very fast, but couldn't stay together long enough to finish the race. I'm not so sure a Chevy engine was cheaper to use when you add up all the costs of trying to keep them on the track.

Also GM had Pontiac, Oldsmobile, Buick, and Chevy. All totally separate engine designs. If GM did win more races in some years (which I do not doubt), how many GM wins were Chevy?

This is all interesting to debate, but has absolutely nothing to do with what engines were in Shelby Cobra's. They were Ford engines. Even if some clown put something other than a Ford engine in a Cobra back in the day, what does that prove, other than he was indeed a clown?

Although there is a rumor that Shelby went to Chevy first and was turned down. It is just a rumor. I believe the official story was that Shelby was aware that Ford about to put the new small block engine into service (or had just introduced it), when he started negotiations with AC. The small size and weight was likely to work in the AC car. The small block Chevy was both physically larger and heavier. I doubt he would have wanted to go with a Chevy if he could get the smaller lighter Ford engine, when you consider what AC had been using.