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Difference between big block and small block motor mounts?

2196 Views 3 Replies 3 Participants Last post by  mcc351
What is the difference between small block and big block motor mounts? Is there a way to confirm what is installed on your vehicle? The reason I'm asking is that my 69 mustang has a 351w but the previous owner switched it from a 390. The engine seems to sit really low. I'm wondering if I have the wrong mounts. The reason I noticed is because the fan blade is really low ( see my previous thread on fan shroud clearance issues). I took off the fan shroud and the fan blade clears the lower radiator hose by about 3/8". That seems way too close to me...
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This info may help you figure out what you have. Courtesy of Mustang Monthly (I think is where I got this)


There was a good article on all the various engine mounts in Mustang Monthly, Feb 2013, page 52. It gets really into all the part numbers, engines, and body types. For you, the big block mounts lowered the engine 1/2" to clear the hood. It also matters if you have a convertible because of all the body beef-up.

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Thanks. This helps immensely. It looks like the actual problem is the body bracket not the motor mount itself. The article seems to contradict itself ... In photo 11, it says that the body bracket on the big blocks have bolts parallel to the edge. In photo 12, it says that the big blocks have holes not parallel to the edge. Am I misreading this?
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