Im not sure if there is a website or other on this but will a 1998 Lasabre 3.8 work in a 1996 Bonneville???? If not what is compatible???

The engine itself will fit no problem. Some brackets may need to be swapped along with some of the sensors. Sensors changed part #'* between the different years. But, to be safe, swap them all over and you will be fine.

Well thats good news but instead of changing all the sensors wouldnt it be easier to just replace to computer to a 98 Lesabre????

No, the Bville PCMs are different. I should know. I have a 96 supercharged Buick PCM in my 97 Bonneville. It'* not compatible with the sending unit, EVAP etc. But thats a different project i'm working on.(have to wait on HP tuners for an update for my current 97 PCM)

While the engine is out, it will only take 10 minutes to swap out all the sensors. LEAVE THE OIL PRESSURE SENSOR UNTIL AFTER THE ENGINE IS IN. I can't count the number of times I have broken that thing by putting the engine back in.

Believe me, less headache afterwards.

Oh ok, i see what your sayin.... That makes sense...

Well new motor is in and it runs great. Its a 98 Grand Prix supercharged with only 80K. The previous owner spend some cash on the */C and it shows. Lots of power. Before the motor went in i looked at the guts of it and it was very well cared for. Right now im just waiting for the new exhaust since my factory one is not flowing very good. Once it get it breathing better im sure ill be happier than i am now....

Is your original trans still in it?

Well i just hit the 5k mile mark on my car with the engine transplant and ill say that its run like a top... No issues at all........ Love this car....

Gives you a whole new perspective of the car now doesn't it? Same thing happened to me when I upgraded my L36 to L67.

Well i just pulled the blown engine apart a found the issue. it was a broken valve spring. 2 thumbs up to GM for the 3.8, everything looked good. The main bearing show some wear but otherwise there was little sign of wear on the rest of the engine.... For a motor with 175K on it it looked good......