Hey everyone i will be picking up a 67 425 D block B heads for my 84 cutlass Calais that has a 350/350 and was wondering wat all i need to swap over the 425

 

You need the correct exhaust manifolds or headers for a BBO. If you are running the original 307 accessory brackets, you'll need to make a couple of slight modifications to accommodate the taller deck height of the 455. If you are running the 307 starter currently, you'll want a high torque starter. You'll need a larger radiator.

The one thing you WON'T need is new motor mounts, however. Simply bolt the current ones to the 455 and drop it in.

 

So will the accessory brackets from my 350 olds work on the 425 ?will I have any clearance issues with the hood or anything else

 

It depends on which year 350 brackets you have. Brackets from cars that were built during the period when Olds was building both BBO and SBO engines typically have two sets of holes to accommodate the two different deck heights. Brackets from 350s built in the late 1970s will likely only accommodate the SBO deck height and will require mods to fit the BBO.

 

Depending your air filter asm. hood clearance may be tight. A Toronado iron intake will gain you perhaps an inch of room for a taller filter.

Great choice of a 425
B heads are typically seen on 1966 model year engines, not 1967.
Look for the exact application and Engine Unit Number stamp in the flat machined area on the fwd end of the RH head. Please state what that is. R100123T or similar.

Also look for the drill spot in the rib adjacent to the oil fill tube, which indicates a Tornado type D block.

 

Does this help

 

Looks to be a Toronado engine. Good starting point. You will need the .921 lifters for it.

 

^^^^ Look at the date of the original post.

 

Sorry I'm getting old

 

It beats the alternative! We all make mistakes, nobody walks on watet. It was good to see Chris Witt's post. It reminds me of better times, Oldsmobile-wise. Jmo.