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Jamerian
01-02-2008, 08:48 AM
I own a 1987 Pontiac 6000, with the incredibly loud Tech IV engine. I love it, it has never disapointed me but luck would have it that i have the chance to swap for a 2.8 for free or for an extremely low price. I have no idea what goes into swapping so i need some tips. At my school we have lots of these engines lying around and i found an LB6 v6, that i believe is the rightful engine with 128000 kms on it. My teachers think its a good learning project so im going for it. These are the things that im guessing are going to be changed...

- Fuel delivery ( at the junction between line and original tbi system )?
- Computer?
- Engine subframe?
- Tranny?
- Exhaust?

There must be so much more that goes with engine swapping, so anything would help, thanks

87Cutlass Ciera
01-02-2008, 01:48 PM
I like this idea, in fact, it's almost what I might do with my Cutlass, swap the 2.5 for a 2.8.
The 2.8 and 2.5 have the same bellhousing, so the transmission will bolt up to the 2.8, after that I don't know much about transmissions. :p The 2.5 is fuel injected, and the pump is in the tank. There are two 2.8s out there for these cars, one which is carbed and one which has a multiport fuel injection, which one do you have your hands on? I'm going to say that there will be some work in rearranging your fuel delivery system for both of these, chaning the sending unit and things like that. I think both engines will bolt up the same on the subframe. 3 motor mounts. two on the bottom. (one is a cradle on the passenger side, the other bolts up to the tranny and the enigne at the same time), and then there is the torque strut on the top of the motor nicknamed a "dog bone." I have no clue about the computer. The exhaust if you're doing the job right, then you would need to change the whole system. Make sure you label everything and set all of your nuts and bolts aside safely. Preferably, I like to take pictures of things as they're coming apart and when I go to put it back together, if I have any questions I just have to look, and It's like a finding waldo puzzle! Good luck, I think it's a great idea!

dcjredline
01-02-2008, 02:26 PM
You will need a new Fuel pump no matter which engine (Carb or FI) I am not sure about the sneding unit though. Computer and prolly a little wiring will need to be changed also (FI only) computer will prolly be eliminated if going to carb.Thats my only input.

a1veedubber
01-02-2008, 06:14 PM
You will need a new Fuel pump no matter which engine (Carb or FI) I am not sure about the sneding unit though. Computer and prolly a little wiring will need to be changed also (FI only) computer will prolly be eliminated if going to carb.Thats my only input.

I don't have much to add but will second this. The MPFI 2.8 runs at a higher fuel pressure than the 2.5. Depending upon how easy this is I might be considering this as an upgrade for my 86 2.5 too!

On another note, you go to a school with a lot of cars laying around to play with? Awesome! Back in the late 90's I was in the GM BSEP course and had scads of low milage factory donates GM cars to work on. When we were done with them they had to be destroyed, we would actually take hammers to every part on Corvettes & Firebirds with less than 50 miles on them! :( We even had one of the pre-production Beretta Indy 'verts too. Total sweetness.

Jamerian
01-02-2008, 09:49 PM
Ok, nice.. so i keep the same rad too? Thats amazing that i can keep the same tranny and subframe, so i dont have to drop either. Yes, the fuel pump makes sense, theres no way im going with carb though so i do need a computer. Where can i get one of those?.

Yea, im very lucky to be at this school, i save a lot of money, i yanked my subframe and power steering rack from a celebrity with the same engine, so that was a "would be" expensive fix for free. I also robbed alot of components from that engine, including the tranny, so i have an extra one kicking around my garage incase something happens.

Hey, would any body be able to post a pick of their 2.8 engine , just want to do some comparing to see where things would go?

Electra_T_Type
01-02-2008, 10:13 PM
Fuel pumps different? Last I checked at autozone the 2.5 and 3.8 Centurys used the same one, dunno about the 2.8 but 90% sure its the same.

86euro
01-03-2008, 02:29 AM
Multi-port FI runs at about 45psi where tbi only runs around 12, so the pump will need to be changed. Also needed will be exhaust, computer, engine wiring harness, underhood fuel lines, AC compressor, AC lines and evaporator, alternator, coolant hoses, power steering pump, power steering lines, air intake tubing and air cleaner, and likely other stuff too.

Jamerian
01-03-2008, 07:33 AM
nice, i was waiting for a list lol so..

exhaust - do i need a cat convert (plz say no) and will the manifold link up at all will the rest of my original pipe?

Ac compressor- i guess this doesnt really matter since i never had any to begine with, i should just disassemble it from the engine.

alternator - still attached

coolant hoses - so i can keep the original rad?

power steering pump - still attached, but they look the same

" " lines - really?

air intake and cleaner - i know this is going to be difficult.

86euro
01-03-2008, 11:22 PM
nice, i was waiting for a list lol so..

exhaust - do i need a cat convert (plz say no) and will the manifold link up at all will the rest of my original pipe?

Ac compressor- i guess this doesnt really matter since i never had any to begine with, i should just disassemble it from the engine.

alternator - still attached

coolant hoses - so i can keep the original rad?

power steering pump - still attached, but they look the same

" " lines - really?

air intake and cleaner - i know this is going to be difficult.

The cat is welded to the headpipe, and the headpipe is different. If it were my car, I would replace ALL of the exhaust because the 2.8 cars are supposed to have 2.25 tubing as opposed to the four bangers 2 inch. It actually seems to make a difference in upper rpm's, too.

You will need an AC compressor mounted so the belt has something to go around. The 4cyl AC lines will interfere with the upper plenum of the v6.

Rad hoses are different, rad is the same. I think the heater hoses are different too.

I think the PS pump actually is different, so are the lines that connect it to the steering rack.

Air intake is pretty simple, just some tubing, MAF, and filter canister.

Basically you need to go to the junkyard and rob an '87-'88 2.8 A-body of everything that looks different. '89 used different fuel lines and fuel rail.