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This is my 3.4 swap.
My car is a 1995 Olds Acheiva with a 3.1, clocking 129000 miles.
Upon blowing a head gasket I said I had enough. 6 months ago I had resealed the lower intake and I wasn’t about to do it again. After I pulled the motor and broke it down, I discovered the head gasket failed on slug #2.
The donor motor is a 3.4 from a 2004 Olds Alero with 9000 miles on it.
I got the original instructions from 3400swap.com, print a copy and follow along. Here are my differences.
1.) Motor Mounts. I reused all my stock mounts and brackets.*
2.) Fuel lines. I removed my 3.1 fuel lines at the FPR and at the rail. Be careful not to loose the o-rings that are in there. I did this because I wanted to retain the stock ’04 FPR, injectors, and rails. In his article he thinks that the ‘00+ injectors are 22.5#. I plan on upgrades so I figured I keep them. More on that later. The other reason is the fuel lines on the 3.4 route under the exhaust crossover. There was little to no heat shielding there for the fuel lines, I preferred the way my stock lines ran up over the cross over pipe and how the exhaust shielding looks to do a better job. It was also easier and I didn’t have to modify anything, just unbolt and re-bolt the upper intake.
3.) Engine Wiring Harness. This was pretty much untouched on the car side of it. The purge valve, 3.1, was located behind and below the coil packs on the rear head. On the 3.4 it is located by the TB. I added about 10” of wire to the plug so it would still look stock.
4.) Battery Harness. Never touched it, I used my 3.1 starter. Ok I cleaned it.
5.) ECU. Never touched it.
6.) Transmission. I changed my tranny lines with stock lines, my leaked. Boy is it a lot easier to do when the motor is out! Otherwise nothing.
7.) Heating and cooling. This was a bitch! I used the heater core piping that was on the 3.4 Like he said I had to tweak it. I still ended up running 2 6’ lines behind the brake booster down behind the rack and then over to the core. This was the hardest part of the job! Acheiva ain’t got much room! I put a dexcool rad cap on. I like the little orange circle J I removed every spring style hose clamp I could find on the motor and replaced them with good hose clamps. Otherwise, I used my stock rad hoses.
8.) Alternator. I used my stock 3.1 alternator and brackets. One mod. The bar bracket that is on the right side of the alt. That is the nut to the bolt that secures the right side of the alt to the mount bracket and then to the corner of the intake. I had to elongate the mounting hole of the bar bracket, because the difference of the intake to the alt bracket is shorter than the 3.1. Makes sense, the 3.4 intake is bigger! Also I then shortened the bar about 1/16” on the bolt side/bracket side and ¼” on the intake side. DO NOT USE PLIERS ON THE 2 STUDS FOR THE ALT BRACKET!!! They have a 5.5mm head on them, do it right or don’t do it at all!
9.) Knob on the timing cover. I took a hand grinder to it, never had the timing cover off. It don’t get more basic then that when it comes to fabrication! You can’t see it anyway. The knob wouldn’t allow the front engine mount bracket to line up properly. It does now.
10.) I used the pulley off of my serp. Belt tensioner and used the 3.4 tensioner, then was able to route a new serp belt in the stock 3.1 config.
11.) Harmonic balancer. Used the 3.4 balancer never had it off.
12.) Knock sensor, I swapped in the 3.1 sensor, plug is different.
13.) Crank position sensors. They are the same sensors, I used the 3.4 ones I got on the motor. Cam sensor I changed to the 3.1 sensor. I had to cut the Injector harness on the 3.4 to remove the 3.4 cam sensor from the harness.
14.) Oil pressure sender. I used my 3.1 sender, I have a gauge in my dash and retained its use.
15.) Injector harness. As you know I used the 3.4 injectors. I did some research and found out that the map sensor power wire is spliced into the power wires on the 3.4 injectors. I found and matched the wires and put the 3.1 injector plug, and MAP plug, onto the 3.4 injector harness. Wasn’t that hard to do. If you do this make sure you do it right, solder and shrink tube!!!! That’s my dad and me extending the purge harness.
16.) Air inlet, stock. I got a K&N filter, who doesn’t?
17.) I think it was a 3/8 allen.
18.) ECT sensor. I bought the 3 pin ECT for $19 and I got the plug from Borg Warner for $23. It’s so much easier than tapping the head. I also reran the gauge wire up through the injector harness so it looks stock.
19.) I used the 3.4 map sensor and I would have used it’s purge valve but it was damaged in shipping, so I reused my old purge valve, in the 3.4 location.
20.) Throttle Bodies. I did the linkage shaft change like he showed, only I got a sheet metal lock nut to screw back onto the shaft under the TPS to replace the lock washer the factory had put on there. I used the 3.4 TPS and IAC. (pic shows size difference)
21.) I used the 3.1 back exh manifold. I didn’t have time to mod the exhaust. I did knock out the guts of my cat, it was clogged, screw emissions. I also capped the egr ports in the manifolds. I used the old exhaust manifold gasket, cut out a chunk, and drilled some holes in it. Works fine. No running problems. I do get a SES light about the EGR, that’s it.
My car is a 1995 Olds Acheiva with a 3.1, clocking 129000 miles.
Upon blowing a head gasket I said I had enough. 6 months ago I had resealed the lower intake and I wasn’t about to do it again. After I pulled the motor and broke it down, I discovered the head gasket failed on slug #2.
The donor motor is a 3.4 from a 2004 Olds Alero with 9000 miles on it.
I got the original instructions from 3400swap.com, print a copy and follow along. Here are my differences.
1.) Motor Mounts. I reused all my stock mounts and brackets.*
2.) Fuel lines. I removed my 3.1 fuel lines at the FPR and at the rail. Be careful not to loose the o-rings that are in there. I did this because I wanted to retain the stock ’04 FPR, injectors, and rails. In his article he thinks that the ‘00+ injectors are 22.5#. I plan on upgrades so I figured I keep them. More on that later. The other reason is the fuel lines on the 3.4 route under the exhaust crossover. There was little to no heat shielding there for the fuel lines, I preferred the way my stock lines ran up over the cross over pipe and how the exhaust shielding looks to do a better job. It was also easier and I didn’t have to modify anything, just unbolt and re-bolt the upper intake.
3.) Engine Wiring Harness. This was pretty much untouched on the car side of it. The purge valve, 3.1, was located behind and below the coil packs on the rear head. On the 3.4 it is located by the TB. I added about 10” of wire to the plug so it would still look stock.
4.) Battery Harness. Never touched it, I used my 3.1 starter. Ok I cleaned it.
5.) ECU. Never touched it.
6.) Transmission. I changed my tranny lines with stock lines, my leaked. Boy is it a lot easier to do when the motor is out! Otherwise nothing.
7.) Heating and cooling. This was a bitch! I used the heater core piping that was on the 3.4 Like he said I had to tweak it. I still ended up running 2 6’ lines behind the brake booster down behind the rack and then over to the core. This was the hardest part of the job! Acheiva ain’t got much room! I put a dexcool rad cap on. I like the little orange circle J I removed every spring style hose clamp I could find on the motor and replaced them with good hose clamps. Otherwise, I used my stock rad hoses.
8.) Alternator. I used my stock 3.1 alternator and brackets. One mod. The bar bracket that is on the right side of the alt. That is the nut to the bolt that secures the right side of the alt to the mount bracket and then to the corner of the intake. I had to elongate the mounting hole of the bar bracket, because the difference of the intake to the alt bracket is shorter than the 3.1. Makes sense, the 3.4 intake is bigger! Also I then shortened the bar about 1/16” on the bolt side/bracket side and ¼” on the intake side. DO NOT USE PLIERS ON THE 2 STUDS FOR THE ALT BRACKET!!! They have a 5.5mm head on them, do it right or don’t do it at all!
9.) Knob on the timing cover. I took a hand grinder to it, never had the timing cover off. It don’t get more basic then that when it comes to fabrication! You can’t see it anyway. The knob wouldn’t allow the front engine mount bracket to line up properly. It does now.
10.) I used the pulley off of my serp. Belt tensioner and used the 3.4 tensioner, then was able to route a new serp belt in the stock 3.1 config.
11.) Harmonic balancer. Used the 3.4 balancer never had it off.
12.) Knock sensor, I swapped in the 3.1 sensor, plug is different.
13.) Crank position sensors. They are the same sensors, I used the 3.4 ones I got on the motor. Cam sensor I changed to the 3.1 sensor. I had to cut the Injector harness on the 3.4 to remove the 3.4 cam sensor from the harness.
14.) Oil pressure sender. I used my 3.1 sender, I have a gauge in my dash and retained its use.
15.) Injector harness. As you know I used the 3.4 injectors. I did some research and found out that the map sensor power wire is spliced into the power wires on the 3.4 injectors. I found and matched the wires and put the 3.1 injector plug, and MAP plug, onto the 3.4 injector harness. Wasn’t that hard to do. If you do this make sure you do it right, solder and shrink tube!!!! That’s my dad and me extending the purge harness.
16.) Air inlet, stock. I got a K&N filter, who doesn’t?
17.) I think it was a 3/8 allen.
18.) ECT sensor. I bought the 3 pin ECT for $19 and I got the plug from Borg Warner for $23. It’s so much easier than tapping the head. I also reran the gauge wire up through the injector harness so it looks stock.
19.) I used the 3.4 map sensor and I would have used it’s purge valve but it was damaged in shipping, so I reused my old purge valve, in the 3.4 location.
20.) Throttle Bodies. I did the linkage shaft change like he showed, only I got a sheet metal lock nut to screw back onto the shaft under the TPS to replace the lock washer the factory had put on there. I used the 3.4 TPS and IAC. (pic shows size difference)
21.) I used the 3.1 back exh manifold. I didn’t have time to mod the exhaust. I did knock out the guts of my cat, it was clogged, screw emissions. I also capped the egr ports in the manifolds. I used the old exhaust manifold gasket, cut out a chunk, and drilled some holes in it. Works fine. No running problems. I do get a SES light about the EGR, that’s it.
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