3.0/915 Installation Checklist

[viejopatron]

OK. I'm almost ready to install a 3.0/915 combo into a '71 last fitted with the 2.2/901. Aside from things like assistants, floor jacks, stands, etc., here's my list of things I need to do on the car itself;

1. Verify fit of ALL mountings; rear mounts and transmission support. Verify support fit.
2. Verify shifting link attachments are compatible.
3. Verify speedometer attachment.
4. Verify tachometer connection.
5. Inspect and replace heater ducts if needed.
6. Verify all ‘open’ engine ports / holes are closed unless accessible after installation.

What have I missed? I'm believe some adaption of the trans support and tach is needed. All reviews and suggestions are greatly appreciated. Thanks.

[don gilbert]

gary, ive done this swap, and the biggist pain are the fuel lines.

[jpnovak]

what year of the 3.0 and 915? Are you keeping CIS or converting to carbs?

While there are many threads on this subject let me give you a few points to ponder.

If you use the 915 transmission mount (901 will not fit) the engine and transmission will "almost" bolt in. The up to 72 tranny tunnel and rear seat stamping is narrower and lower than 72+. You will need to clearance about 3/8" to clear the nosecone of the 915. You will likely have to cut off the most forward of the emission line bracket as it will not clear the 915.

You will need the 915 clutch cable, 915 shifter and 915 shift rod. The 901 shift rod is too long and the shifter is "backwards" with respect to gear shift pattern and shifter lockouts.

If you have a 75 or later 915 you will need to convert to electric speedo. This means running a wire to the dash and using the correct speedo gauge.

If you have a 75 or later 915 you will need to swap your trailing arm stub axles from the 108mm 4-bolt, 2-pin variety to the 100mm 6 bolt variety. You will also need the actual CV shafts/joints. If you have a 72-74 915 the CV axles will be a bolt in. There are other solutions besides this one but none are as easy.

Wiring is simple. you will swap pins in the 14-pin connector and add a 6-pin CDI. You can not use your 3-pin CDI as it can not be triggered from the magnetic trigger in the 3.0 distributor.

The stock tach will still work. It gets a 12V square wave signal off the black/purple wire.

You will need a CIS fuel pump, accumulator and plumbing. YOur 71 will have a return in the tunnel and to the tank. Of course, the CIS will usually have cavitation problems under acceleration so upgrading to a later tank is recommended.

[viejopatron]

Thanks for the info.

Jamie - The engine is a 1981 and the transmission is a modified ‘77 with flanges to mate with the shafts. I’m going with Webers, no CIS. Do you have any pictures of the clearance cuts needed?

[jpnovak]

Pull the nosecone off the 915. Bolt the cross member to it. Use this as the test part for clearance. you will need to bump the tunnel at 11 O'clock to clear the mounting ear of the nose cone. Just below this about 10 o'clock are the two emission lines running through a rectangular mount. I cut the line and then pushed the two lines below the transmission ear.

Oh, don't forget to buy a new nosecone gasket. They are just a few dollars.

If you are running carbs, just pull the entire wiring harness off the 71 and install it on the 3.0.