So I have a 347 in my 66. But, My 75 bronco is a little sluggish. So I was thinkin maybe getting a new long block for my bronco. However, since my mustang with the 347 just runs terrific, why not screw that up and take out that power plant and put it in my bronco. Then, put a 363 or 427 in my mustang!
Am I thinking clearly?
So how tight is a 351 block in a 66? I know I will need new headers, but it that all? for 2k difference I may as well have both of them be awesome right?

 

I would go with the engine swap from the Mustang to the Bronco, with a new engine for the Mustang.

I may be wrong, but I believe the 363s are based on a 302 block and the 427s are based on the 351 block. The 363 shouldn't be an issue at all as far as room.

Good luck!

 

you are correct about the blocks. Is anyone on here running a 351 block in a 65 or 66

 

I know FPA makes swap headers for that...

 

I’d keep the 347 in the mustang and put the big block in the bronco. 65-68 mustangs run better with small blocks as far as handling and drive ability

 

NoReins put a 351 based engine in her car, I remember she had some type of issue getting the right oil pan but I think that was due to the aftermarket crossmember and power rack making it a tight fit. Hers was a 67 though, so it might have been a bit wider between the towers, not sure.

 

I️ had a 65 coupe about 10 years ago with a Windsor in it. Was very very tight, it came that way and sold it that way, but the 289-302 is a much better option. Also had a 67 coupe with a fully built 351w as well and it had more room for than the 65 but still not as good as a 289 based block. Id take a 331-347 stroker in a 65-68 Mustang all day over 351+ sized block

 

The handling and drivability should be the same. There is cery little difference in the 351 and 302 blocks. Just a slightly different deck hieght. The wieght is nearly the same. The difference is only about 50 lbs.
I dont think i can get mi h more power out of a 302 iron block and i want more juice in the 66.

I am so far leaning on a 351 based 427 in the 66.