Engine swap in a 66

[rdawg999]

Hey, I wanna know if there are any major changes I would have to do to the engine bay to pull a stock 289 out and replace it with a 351W? I figured I would need stiffer suspension, but anything else? Thanks for the help.

[MagicRat]

I don't think stiffer springs may be in order. The 351 has a 1 inch higher deck height (and bigger crank) and is a bit heavier, but no more than about 50 lbs or so. Some of the weight gain could be made up by using an aluminum intake. The 289 intake will not fit the 351.

You can still use the original exhaust manifolds but they would sit almost an inch higher and slightly wider apart so the original exhaust might not bolt up.

Use the same flexplate or flywheel that came with the new engine. Some of the 351's were externally balanced while your 289 was internally balanced (I think) so the housing may not interchange.
If the 289 was a manual and the 351 is from an automatic, you may not have a clutch pilot bushing in the rear of the crank. This may be a problem.
Finally, check hood clearance with the air cleaner, as the 351 is a slightly taller engine.

[351wStang]

With a car that old you shouldnt have any problems. Pull the 289 (and give it to me) then set the 351w down in there and basically be done with it. They both have the same bolt pattern so the same tranny can be used. Should be fun, and very easy. Good luck.

[rdawg999]

Originally Posted by 351wStang

With a car that old you shouldnt have any problems. Pull the 289 (and give it to me) then set the 351w down in there and basically be done with it. They both have the same bolt pattern so the same tranny can be used. Should be fun, and very easy. Good luck.

Alright, thanks. You said the bolt pattern was the same for the tranny, what about the engine mounts? And would I have to stiffen anything before hand or just drop and bolt right in?