Rebuild the 2.8 or put in a 3.4/3.8?

[2.8 Grand Prix]

Hello,
My 1988 Grand Prix has the 2.8 which is by no means a bad engine, but with 250,000 miles, time has taken a toll on performance. It only runs on 5 cylinders. I was told by the previous owner that it needs the heads rebuilt. How long would it take to rebuild the heads? How much would it cost?
I am wondering whether it would be easier and less costly to just put in a new engine. I have located a nice, good running 3800 out of an Oldsmobile. It comes with the complete wireing harness, computer, and transmission. Would it fit? Thank you for any suggestions or other alternatives.

[robertisaar]

3800s aren't our type of thing.

if you insist on using it, check w-body.com for more help.

the easiest thing to do is probably just drop a 3100 or 3400 in it. you'll pick up at least 30HP even with the small port motors.

[2.8 Grand Prix]

Ok, thanks!

Is replacing the engine still an easier alternative to rebuilding the heads? I am trying to do this with the least amount of money possible because I just graduated from college and don't have a lot of money right now.
How long would it take to rebuild the heads? I am just trying to find the easiest way to do this right now. If I do replace the engine, I will still keep the 2.8 and rebuild it, but I would really like to keep this car running as long as I can for now.

[asylummotorsports]

Have a look on www.car-parts.com for engines in your area.

A 3100 is good, a 3400 is much better. A 3500 is the most powerful option, but involves a little more work and expense.

In the long run you would likely be better off swapping to newer technology than rebuilding a 2.8, and it may also end up costing you less.

And at 250K just doing the heads is a bandaid.

[ghrarhg]

It would likely be much cheaper to find a 3x00 and swap that in rather than rebuild the 2.8. With 250,000 miles, it's probably a good idea to do at least a clean up bore. Then pistons and rings to go with it. Then on to the top end. Cost and time depend on what's wrong with them right now. Just cost of gaskets for the top end plus any head work would probably get you a running 3400.

The heads can be pulled with the engine in the car, so that may make it easier, but if you're doing anything to the block, you'll have to pull it.

My vote is motor swap.

[2.8 Grand Prix]

Ok, thanks guys!

I will definately go with an engine swap. Now all I have to do is try and find a decent one with good miles. I'll check the website you posted and see about that. Thanks again.

[no_doz]

get a set of 3100 or 3400 heads/intake/tb, the custom pushrods to match, & some headers, as well as a tune from wot-tech & you should be thrilled with the power you get. or you could get a set of TGP exhaust manifolds & a t25 or t28 turbo, & have flybynight on tgpforums.com tune you a chip to match.

you could be gradually buying parts & make it an crazy badass ride without a full out engine swap. if you go the route of the turbo you should get:

a set of pistons from summit racing or wot-tech
ARP studs for the connecting rods
manual boost controller
walbro 255 lph fuel pump
boost gauge
intercooler
the intake piping
tgp headers
stiffer valve springs
chip tuned for boost (flybynight on tgpforums.com would be a good person to talk to)
bigger injectors
accommodating oil lines

or you could do the 3400 heads with a t25 or t28 turbo which will require different headers & i you went that route you could skip the t25/t28 & go for a T4 & really push some power.

there are lots of options even with the stock engine

[ghrarhg]

get a set of 3100 or 3400 heads/intake/tb, the custom pushrods to match, & some headers, as well as a tune from wot-tech & you should be thrilled with the power you get. or you could get a set of TGP exhaust manifolds & a t25 or t28 turbo, & have flybynight on tgpforums.com tune you a chip to match.

you could be gradually buying parts & make it an crazy badass ride without a full out engine swap. if you go the route of the turbo you should get:

a set of pistons from summit racing or wot-tech
ARP studs for the connecting rods
manual boost controller
walbro 255 lph fuel pump
boost gauge
intercooler
the intake piping
tgp headers
stiffer valve springs
chip tuned for boost (flybynight on tgpforums.com would be a good person to talk to)
bigger injectors
accommodating oil lines

or you could do the 3400 heads with a t25 or t28 turbo which will require different headers & i you went that route you could skip the t25/t28 & go for a T4 & really push some power.

there are lots of options even with the stock engine

I did all that to my 2.8. T25 + Turbo cam, 3400 heads, basically everything you have listed except pistons and arp fasteners. If my car had to be my DD, I would go 3400 in a heartbeat for about 1/3 the cost. I like the setup I have, but for cheap and reliable everyday usage the 3400 wins hands down.

[IsaacHayes]

Check out domesticcrew.com there is a swap guide there for putting in a 3400 into an older vehicle. Going into a W body I'm not sure but I think your stock mounts *should* bolt to the 3400.

[robertisaar]

Check out domesticcrew.com there is a swap guide there for putting in a 3400 into an older vehicle. Going into a W body I'm not sure but I think your stock mounts *should* bolt to the 3400.

certain Ws did have 3400s... although the dogbone mount may be a different length...

[2.8 Grand Prix]

Thanks guys!

I am really getting excited about this. I'll just have to wait until I get a full time job so I can afford to do all of this. The good thing is, the tired 2.8 still drags itself around town just fine. It's just loud and not very fast. Well, thanks for all your help so far!

[no_doz]

yea there were some of those cars that came with the 3400-my friends sister had one & it was a pretty dandy running car for stock :P

[2.8 Grand Prix]

Back to the drawing board.

Well,
I talked to my grandfather, and he is suggesting taking the car to a mechanic and having them look at the car to see if there is anything else wrong with the engine. He says that a junkyard engine might have something wrong with it too. That makes sense. He thinks that if there isn't anything major wrong with the engine (besides the heads), that I could have the heads rebuilt and maybe get another 50,000 miles out of this engine.
I've decided that if I really want to get a new engine, I need to find one that the salvage yard owner knows/guarantees that it runs good. So for the time being, I'll just let the car stay the way it is.

[robertisaar]

most yards around here will give you a 30-day warranty on the motor... if there is something majorly wrong with it, you'll know within that time.

[2.8 Grand Prix]

Would salvage yards have "low" to "mid" mileage engines for under $250? I am really trying to get this car going good with a little money on hand.