I hafe to replace the motor bareings in my 2.8. Am I just better off getting the 3.4 and putting it in or is it easier to just replace the bareings. I would be very greatful if any one could give me some numbers on the cost of things.

 

It's probably easier to get a good low mileage 3.4 and put it in. Althought I have changed bearings in my 83's 2.8, it is more involved because after removing the engine you have to disassemble it to install the bearings. If you went to a 3.4 you'd only have to remove the engine and swap parts between the two motors (easier). Cost wise, replacing the bearings and crankshaft would run about $200. I would strongly recommend a full valve job (200) and all of the Gaskets about 150. So that's about 550 to rebuild the 2.8. The 3.4 used would probably cost about 800-900. Then I would budget for about another 150 to cover gaskets, and anything else that may come up

 

You have an 82-84 carb'd motor, right? The crankshaft on that motor has different main bearing sizes; the #3 journal is the largest. An 85-up 2.8 or 3.1 or 3.4 will have the "large journal" crank, which has all the journals the same (#3's) size, which makes for a stronger crank. I agree with MD, doing a motor swap will be easier. Don't forget if the bearings are messed up, you'd have to get the crank ground, which is going to cost money. Like MD said, you're going to spend the same amount, and you'd just be doing the crank bearings.

Don't forget, too, if you can't find a 3.4, you could also use a 85-up (87-up is best) 2.8 or 3.1, which might be even cheaper than a 3.4. My local junkyard told me $100 for a running f-body 2.8. Then again, I'm there all the time ("You're back? I just got a Firebird for ya!"), but I can't see a junkyard wanting more than $200-$300 for a 2.8 block. Like I said, try to get 85-up, at least.

 

Since yours is a carb'ed 2.8 (older style design) you may just need an oil pump! Those oil pumps were a aluminum caseed housing with steel gears. They wore out the alum. housing and would start knocking as the engine warmed up.

 

is the oil pump easy to replace
in both the carbed and MPFI v6's???

doesnt he have a oil pressure gauge ...(whats the ideal oil pressure when teh car is hot and when its cold???).that should tell him if his pumps bad / not

 

If the pump is bad, it will start to knock after about 3-5 minutes of running. If it knocks right from the start, the pump has grenaded itself, or theres bearing damage. Oil pressure should be right around 10psi for every 1000rpm (roughly). Once the oil pan is dropped, the pump is real easy to change, just make sure it is primed before the engine is started.