Project TR7 part 7: A complete brake job
Old and rusty undersized front rotor
When it comes to the brakes on an old car, I take no chances and cut no corners. I usually rebuild, repair or replace most everything. It’s foolish — and potentially dangerous — to try and save a few pennies by reusing old brake parts because they look OK. But for Project: TR7, a simple rebuild would only restore an inadequate factory designed brake system to, well, working inadequately — and that’s unacceptable for a car that could see daily use.
For some reason, Triumph didn’t bestow the TR7 with confidence-inspiring brakes. The undersize front calipers and pads are the same as those used on the spindly MG Midget. And no matter how hard you step on the pedal, you can’t lock up the rear brakes. A few quick, hard jabs of the brake pedal cause the pads to heat up quickly and the brakes to fade.
Green stuff brake pads on the right, stock on the left
Three tried and true modifications to the stock TR7 brakes will increase braking efficiency just enough for safe street driving. First, we’re going with Green Stuff Kevlar front pads, which have more bite than the stock pads, Next, we’re changing the amount of hydraulic pressure that gets sent to the front and rear brakes. And, finally, I am installing a set of rear wheel cylinders from the TR8 that improve rear braking efficiency and reduce pedal effort.
While working on Project: TR7’s suspension system, I found four of the car’s steel brake lines were rusty, pitted and corroded. They weren’t leaking, but who knows how much longer they’d last. While you can no longer walk into your local British Leyland dealer and order new brake lines, there are options. You can make your own, which requires a flare kit, special tools to bend the mild steel lines you can buy at most auto parts stores, and cutting tools. Or you can do what I did and send the old lines out to be remade by professionals. That way you’ll get new hydraulic fittings and new steel brake lines that fit perfectly.
Last year, I chose Classic Tube in Lancaster, New York (classictube.com) to remake a pair of transmission cooling lines for a 1981 Triumph TR8 with a factory automatic transmission – one of just 13 made that year. The reproduction parts fit perfectly. And so, I sent four of Project: TR7’s old brake lines to Classic Tube. A week later, four new exact reproductions made of mild steel were handed over by the FedEx man.
The old rusty brake lines and the new replacements
New brake lines installed, a perfect fit
TS Imported Automotive in Pandora, Ohio, (tsimportedautomotive.com) provided braided steel flexible brake lines to replace the 40-year-old factory rubber hoses. The Wedge Shop (thewedgeshop.com) in Taunton, Massachusetts, sold me a pair of rebuilt calipers — the originals looked a bit too rough to rebuild — and a new, custom-made brake metering block that enhances brake performance by increasing the pressure sent to the rear drum brakes.
New proportioning valve bolts right in
Old proportioning valve looks pretty tired
The Wedge Shop’s proportioning block fits perfectly in place of the original Triumph part and sends 50 percent pressure to the rear brakes. The recalibrated brakes have another handling benefit: The TR7 won’t nose-dive under hard braking. I am using fatter tires, so I am not concerned with the rear brakes locking up.
Getting the rear brake drums off has been the toughest job I’ve done yet on Project: TR7. Apparently, the car was parked for a decade or so with its emergency brakes on. The wheel cylinders rusted frozen with the shoes pressed hard against the drums. It took a solid hour of banging and prying and cussing, using a BFH, a ball-joint fork on the rear ridge of the drums — and some choice X-rated swear words — to force the drums off.
Brake drums resurfaced
Small hole drilled on the left to take TR8 rear wheel cylinder
The TR7’s original Lockheed brake shoes show very little wear. Still, they were replaced, and the drums were turned. Installing the TR8 rear wheel cylinder required drilling a new hole in the backing plate for the cylinder’s locating peg.
Rearbuilt rear brakes
The last thing, rebuilding the master cylinder after honing the inside, went easily. And then came time to reassemble the brakes. That consumed the better part of a Saturday, but now the brake pedal is firm and I have 100 percent confidence that the TR7 brakes are good to go — and stop — without drama.
Rear brake rebuilt
Rebuilt front brakes
Here’s how much it cost to overhaul and improve Project: TR7’s brakes:
With the brake system overhauled, now the real fun begins on Project: TR7’s resurrection. It’s time to open up the engine and start adding performance parts in a bid to boost horsepower by nearly 40 percent.
But the first order of business is to deliver the radiator to a local Detroit legend named Mel. Turns out, he’s worthy of that reputation.
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