Now that summer is well over, its time to work on the electric Datsun again.

3 main features missing from the truck:

• brake assist
• power steering
• heat

Brake time.

The original truck had engine, which produced vacuum. That vacuum was used for powering things like the brake booster.

Being there’s no longer an engine, and thus no vacuum, we need to add brake assist back into the truck some how.

Two options:

1. Electric vacuum pump, plumbed into the original brake booster
2. Electric brake booster, replacing the original vacuum booster

Option 1.

Vacuum pumps are a fairly straightforward, and bit clunky as you are just “adding on” noisy parts.

Vacuum pumps from diesel vehicle works well, you just need 12v and a way to switch-off the pump when enough vacuum pressure is built up (vacuum switch!).

its a fairly indirect and inefficient way of providing braking assistance.

electricity-> vacuum pressure-> brake pedal assistance

But its simple and safe as you are not messing about with new brake parts.

(if you don’t know what you are doing)

Option 2.

Electric brake boosters are efficient and powerful. There are many variants out there, but the most common, and well understood one is the bosch ibooster. found in every tesla, and a lot of new vehicles theses days.

It’s an electric motor that helps your foot push the brake pedal.

that’s it!

electricity -> brake pedal assistance.

much more elegant and efficient (and powerful) but requires some custom brackets and plumbing to work.

*NOTE if you don’t know what you are doing, stop, because your truck might not....

How I installed the Ibooster in my 720 pickup:

The unit I used is a gen2 bosch ibooster, out of a late tesla model Y (2023+).

The tesla ibooster has a dual 1″ bore MC (master cylinder)

The Nissan/Datsun 720 has a dual 14/15″ bore MC, very close in size!

The ibooster provides a lot more brake assist than the vacuum booster did, this makes up for the bit of extra effort required to pushing the brake pedal with the slightly larger MC (because hydraulics). A nice little balanced upgrade in braking performance!

note: The 720 MC has a residual valve for the drum brakes, built-in, the ibooster dose not.

The ibooster MC dose not have any residual valves. So an additional 10lbs residual valve was installed in the brake line for the rear drum brakes !

Supplies:

• 1x tesla model y/3 ibooster
• 1x ibooster harness/connectors
• 1x 40amp fuse, 5amp fuse
• 2x M10x1.0 inverter x M12x1.0 bubble brake line adapters
• 1x 10 lbs residual valve (for drum brakes only)
• 1x original brake pedal clevis and push rod
• 1x M8x1.5 female x M10x1.5 male coupling
• loctite
• 1x firewall spacer bracket

step 1. Testing:

Start by testing the ibooster on the bench to make sure your unit works! check out the (simple!) wiring needed over at evcreate. it should power up and self calibrate with permeant 12v and ignition +.

step 2. Push rod:

Remove your stock brake MC/booster assembly. Keep the pushrod, clevis and the firewall bracket.

Remove the pedal clevis from the ibooster pushrod, but keep the m8 push rod on the ibooster.

Apply some Loctite, then thread the M8 x M10 coupling into the original push rod assembly. (M10 male end of the coupling into the M10 female end of the push rod)

Then thread the modified push rod assembly onto the ibooster pushrod. (Female M8 coupling end onto the male M8 ibooster pushrod end)

step 3. Fire wall bracket:

To make a new mounting bracket, we will need the distane from the fire wall to where the ibooster sits based off the push rod length.

Re-connect the push rod clevis onto the brake pedal and measure the distance between the fire wall and the matting face of the ibooster, with the pedal in its neutral position.

Once measurements are done, you can disconnect from the pedal assembly.

Next cut off the vacuum booster matting face side from the firewall bracket.

After that cut out a new plate that mates with the ibooster.

Weld on the new ibooster matting plate to the firewall bracket, spaced so it matches the distance we just measured.

step 4. Assembly:

Bolt the new fire wall bracket to the ibooster, then to the firewall, and connect the pedal clevis.

thread in the brake line adapters into the tesla MC.

Now carefully bend the 2 original brake lines into position and thread them into the ibooster, through the adapters. They shouldn’t be too fare off from their original position, 1-2in or so. You may want to make a new line off the branch from the front brakes to the MC.

*NOTE(only needed for drum brakes) install new flare nuts in the brake line that runs to the rear drums. Install the residual valve inline, with the flow of the valve going towards the rear.

step. 5 Wiring:

Wire the ibooster to permeant 12v lines via a 40amp fuse, and the ignition line via a 5amp fuse. detailed wiring info here

step 6. Bleed and speed:

bleed your brakes!

now feel the braking POWER!

silent, powerful, and strong brakes in your truck 🙂

time to add power steering…

If there’s any interest I can provide a ready made kit you can bolt into your truck for upgraded braking performance