i'm looking to put a new engine in my 96 deville and was wondering if the 4.6 out of a 2005 would fit in it without any modification. if anybody knows i'd appreciate the info. thanks

Nope, totally different engine, and engine controls. Stick with a 96 to 99 engine, with your intake on it.

Short answer: NO.

Been discussed in here and Northstar Performance many, many times. Too many mechanical and electronic differences - two different engines and control systems.

Best bet - rebuild the 96 engine to new specs - there is practically nothing you can do as far as aftermarket or power gains, so keep it clean and tuned. You could try www.westersgarage.org for a mild PCM tune, but that won't net you much.

well if my best bet is to rebuild can anyone point me in the right direction to find the parts for the internal and the gasket set without going to the dealer?

What is the condition of your engine now - why are you rebuilding it??

Even high-mileage Northstars usually don't require rings or bearings, so unless your halfcase seals are leaking there's no sense in taking the block apart (the block is in 3 pieces: cylinders, halfcase [4-bolt mains and stud girdle all in one], and oil pan [part of the structure, not an add-on])

The heads are usually good also - maybe valve seals and a new set of hydraulic cam followers ($$$). Sometimes exhaust cams ($$$). Check the timing chains (3) and chain tensioner and slipper faces for any wear. Check the timing chain intermediate sprocket for bore wear. The oil pump is driven by the crankshaft pulley, so there's a very special torque process on reassembly, also very specific on timing the chain drive sprockets and 4 cams.

You MUST Timesert, Norm's Insert, or stud the block for new cylinder head bolts. There is no way to do the job without inserting every head bolt hole. Look at www.northstarperformance.com for stud kits (engine out of the car, and it has to come out the bottom).

Either get a GM/Helm Service manual on eBay or from www.helminc.com. Most gaskets and parts can be found at www.rockauto.com, and for dealer-only stuff try www.gmpartsdirect.com (Flow Chevy/Cadillac in NC), www.gmotors.com (Palm Chevy/Cadillac in N. FL) or call Luke in Parts at Lindsay Cadillac over there >>>>>>> M-F, 9-5 EST