Right you are Doug.....even with a brand new 427 Side Oiler Short Block.... it had to be taken apart & extensively reworked so it would live up to 7000 rpm...always followed this rule..Build it to go to 8000 rpm...never take it past 7000.....
Hum. I had this discussion with one of the mechanics that was with the "continuation Mark IV" GT40's at either the SAAC Convention at Millville or at VIR? I forget which one. It's all bluring into an orgy of horsepower depravity now but I digress.
Now we were talking about 427's that originally went into the Mark II's and Mark IV's. Now in reality, the engine wasn't their part of it. They literally built the cars, pop rivet by pop rivet. Something like 6,000 in each car, but I digress again...my question was why do you build a car around an engine that is intended to go up against the Ferarri's turning upteen bazillion rpm's with an engine limited to 6,000 rpm?
The response was, "what? WTF you talking about?" "You didn't know that?" Huming and hawing and looking back and forth at each other then saying, "well yeh (<NC southern accent), the valve springs only were good for a max of 7,000rpm!"
I said, "that's my point. You're got heads, rods, pistons and a forged steel crank good for 10,000 rpm's. Why?" Shrug shoulders. "I do know?"
The answer really is the 427 is a good base start. Especially for a production based engine BUT it's just a start. Don't worry though. After 65 years, they got it right (but not with stock parts
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