More about the Troopy; add turbo and IC, cruise control, interior build: land-cruiser-78
When I bought a 2001 Troopy in 2019 one thing struck me right away. How bad brakes it had! I was used to driving an 80 with ABS, and if not very good, at least decent brakes. But the Troopy brakes was miserable. It was impossible to get the wheels to lock, and the braking distance was frighteningly long. Except on wet roads, then the wheels locked frighteningly fast. This can however probably be attributed to the Mud tires.
The car has a permissible total weight of close to 3,500 kg and my overland equipped car is close to this.
So, what can you do with this.
Tires
First, consider how big wheels you need. Larger wheels provide greater torque on the brakes and longer braking distance. My car was equipped with 285 / 75-16 Mud tires. I think these were unnecessarily large on an overlander, and Mud tires are not good to drive on, and as mentioned dangerous on wet surfaces. Especially a width of 285 is unnecessary, on most surfaces narrower tires are preferable. Read more about tires here Modifications and equipment.
So I bought new AT tires in dimension 265 / 75-16 instead. This only gives a reduction in diameter of 4% so it does not have a big impact on braking distance, but with AT tires I get at least shorter braking distance on wet roads.
Brake Booster
The most important thing you can do to improve the brakes, at least by simple measures, is to replace the brake booster. On the 78, for some reason, there is a single diaphragm brake booster, while on the 80, which is a car with a lower total weight, there is a dual diaphragm booster that provides more braking power. So a common upgrade is to use an 80 booster.
An 80 booster is bolt-on on a 78 with two exceptions. On the 80 there are normally 4 bolts for brake master, but there are also two bolt versions. At a 78 there are usually a 2 bolt master. It is therefore important to obtain a booster with the correct bolt number. In addition, the rod that goes to the brake pedal is longer on a 78 so this must be extended. If you get a suitable 80 booster then you need to make an extension.
I chose the easy way, to buy a custom booster. Then I got the right number of bolts and extended rod.
The only place I found these was in Australia where Troopiers are very popular. I bought at superiorengineering.com.au and they send worldwide so that is no problem. The booster turned out to be an Aisin booster with an extension rod fitted, so it is probably a standard 80 booster. Aisin is a Toyota company.
Replacing the booster is very easy. Loosen the rod from the brake pedal by pulling out a pin and unscrewing 4 nuts inside. Then unscrew the master, 2 nuts. Carefully pull off the master, being careful not to bend the brake pipes too much. If it is problematic you have to loosen the brake pipes, but that requires a bleeding job afterwards.
Remove the old booster and in with new one. NB. Before fitting the new one, measure the length of the brake pedal rod on the old and adjust the new one to the same length. The bracket for attachment to the pedal is moved from the old one.
I have seen numbers that say that this upgrade will give 30% better braking effect. I have no way of measuring this, but the brakes improved considerably. Now the car dips a lot more in front when braking, even though the front wheels still do not lock.
Load sensing proportioning valve LSPV
This is a valve that is connected to the rear axle and controls the braking force of the rear brake, depending on the load on the rear axle. With heavier loads at the rear, more force will go to the rear brakes.
Many Land Cruisers have been lifted and mine was no exception. Only a few centimeters, but this affects the load distribution valve and must be compensated for, otherwise the rear brakes do not get enough pressure, and the overall braking effect is worse.
Adjustment is done by adjusting the screw on the axle so that the spring-lever comes further from the axle, in principle as much higher as the car is lifted. If this is not enough, you can move the valve itself a little down, about 6 mm at 5 cm lift.
When the car is not loaded, the spring should almost touch the valve. You can test this by pushing the spring upwards and feel it through the rubber around the valve. When pushing, it should move 1-2 mm upwards before hitting the valve.
If you have an equipped car, it will naturally have a larger load on the rear axle and it is not possible to adjust as described above for an empty car. Then the spring must rest against the valve and push it in a little, depending on how much load you have on the rear axle. This is not so easy to assess, but an old trick to test the setting is to drive on gravel roads and then brake hard. The rear brakes should not lock first.
Also check procedure in the Toyota manual.
More about Troopy : land-cruiser-78
