G Pence Article: Nostalgia - 351C 4V Street Motors in the 1970s

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I came across this article the other day:

Nostalgia - 351C 4V Street Motors in the 1970s | The De Tomaso Forums (infopop.cc)

A couple of comments, he mentions a clearance problem with using regular bolts on the Shelby manifolds for 351C. The solution to this is to either use socket (allen) head bolts (which were on mine when I bought it) or the ARP flanged hex head bolts that I used.

Another thing he mentioned is that the staggered shocks cause the cars to "crab-walk" over bumps and he recommends converting to normal shocks if traction bars have been installed. Has anyone noticed their cars, with staggered shocks, crab walking over speed bumps?

 
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I came across this article the other day:

Nostalgia - 351C 4V Street Motors in the 1970s | The De Tomaso Forums (infopop.cc)

Another thing he mentioned is that the staggered shocks cause the cars to "crab-walk" over bumps and he recommends converting to normal shocks if traction bars have been installed. Has anyone noticed their cars, with staggered shocks, crab walking over speed bumps?
  My answer to that is no, or at least I've never noticed it or even thought about that happening.

I do get a loud bang sometimes if and when I hit a bump, but as I have 153 lb Boss springs on the rear plus KYB Gas-A-Just shocks, which are going to get swapped out for GR2's next spring, and with nothing loose, I assume it is the hard shocks causing the "bang".

 

Hemikiller

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One of the more significant statements in his article is the truth about the 351C compression ratios. 

Ford didn’t help alleviate people’s concerns by rating the M code motors one whole point higher in compression than they really were; the 1970 motor was rated at 11.0:1 compression ratio even though its compression was actually 10.0:1, the 1971 motor was rated at 10.7:1 compression ratio even though its compression was actually 9.7:1. People are quite often reluctant to believe Ford over-rated the compression ratio of those motors by that amount.


This is one of those realities you run across when you're crunching numbers on a build, and suddenly the results look wrong when referenced against factory info. Then you realize the factory was FOS and just playing the numbers game to make the engine sound more stout than it was. People love to talk about that 11:1 or 10.7:1 compression, but if you do the math, reality is a little different. 

With a standard FelPro composite head gasket available today, a stock 70 351C-4V engine only manages 9.7:1 compression. The only way it's hitting 11:1 is if the pistons were zero decked and using a .025" gasket. 

70_351c.JPG

The amazing part is how well these engines performed even with the "low" actual compression ratios compared to it's contemporaries, a testament to the design of the cylinder heads. 

 
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