my brother is working on a 69 mercury cougar and has found a 429 4v engine in the junkyard out of a marquis vert will this engine fit with out cutting the shock towers?

 

Let' assume the Cougar engine bay is the same as a 69 Mustang. If so, then it will fit witwhout taking out the shock towers. Take a look at this Boss 429 in a 69 Mustang. You will notice, however there is one hellava suspension under it to support that monster. This is a factory 1969 Mustang Boss 429.

 

Um yep a 429/460 will fit in the 69/70 Cougar. The Cougar was essentially the same car underneath the skin as the Mustang. Cougars have a longer wheelbase for a smoother ride, but all the parts like suspension, engine, and drivetrain will interchange. Driveshafts are a bit different tho. Also Cougars had disc brakes and V8's 67-70. If you find one that doesnt, it was the victim of a downgrade swap, usually to replace parts on a Mustang, then reassembled with the old parts.

A 429/460 will fit in the 67/68 with some work, but its a no brainer in the 69/70. I prefer FE's, especially since Edelbrock makes heads for them now. One of my USAF buds has a 68 428 Cougar XR7 GT. Now that is one sweet ride...

 

As I mentioned a few days ago on this subject, Boss9 cars were NOT factory assembled machines. They were built by a company named Kar-Kraft who DID modify the shock towers to make the engine fit. That said, a standard 429/460 should fit in a 69 engine bay without modifications. The front sway bar and springs in the Boss car are special but the rest of the front end is pretty much run of the mill FE Mustang stuff.