Morris Minor V8 - Suspension and brakes

Front suspension is based on Triumph Herald uprights and wishbones with 9" long springs (350 lbs) and Spax competition dampers. Modified Marina stub axles and hubs were fitted on Triumph uprights. Minor RHD steering rack is narrowed, turned 180 degrees around and fitted in front of the suspension. Note that my car is LHD and this setup turns the wheels to correct directions. Test drives will show if spring rate is correct but it is easy to fix. Shock absorber had to be modified. Triumph has a spring platform on top of the shock but since I had to modify just about everything also this had to be altered. I threaded the top of the piston to 7/16 UNF and fabricated a loop. I also turned a pair of aluminium top plates for the spring. See photos. All this was unexpected work simply because the steering rack would not work where I had planned.

Steering rack was supposed to be Herald item but I considered it a bit weak construction compared to Minor rack. Minor housing is more robust and rack itself is about 8 mm thicker than Herald rack. I did some measurements and found out that Minor rack needs to be shortened some 4 inches. So I simply cut the rack next to the bearing blocks, removed the bit that was left inside the bearing block and pressed in the shortened housing. Rack was cut in lathe and new tie rod threads were cut and threaded. This is an odd thread nowadays, being 1/2" Whitworth but luckily a correct tap was found. Otherwise the rack was rebuilt with new longer tie rods from MG Magnette and fitted with Triumph Spitfire tie rod ends. Steering shaft needed serious fabrication due to rack´s new location. I found out that Mazda 929 has same splines in steering rack pinion as Minor so I could use universal joints from Mazda. Steering column and intermediate shaft from Austin Allegro complete the job. Because I have fitted 3 universal joints also a support bearing had to be fitted.

The plan was to use Marina/Ital front and rear brakes but I chose to uprate even further. While checking brake disc catalogues I found out that BMW 300 series discs could be easily adapted to Marina hubs. These are 260x22 mm vented discs. Marina calibers can no longer be used so I chose Vectra front calibers. In fact any single piston sliding calibers can be utilized, provided they fit inside the wheel. My setup requires 14" wheels.

Fitting was easy:

BMW 320i (E30) discs are diameter 260 mm, thickness 22 mm, depth 35 mm, diameter of flange bore 66 mm.

Marina discs are diameter 249 mm, thickness 9,5 mm, depth 45,7 mm, diameter of flange bore 66,7 mm.

On BMW the disc is fitted on the hub, between the wheel and drive flange. Changing the disc is easy. On the other hand, Marina has the disc fitted between the hub and upright, so to change the disc the hub needs to be removed.

BMW disc is turned on a lathe to open the flange bore to 66,7 mm. This bore guides and centers the disc on a hub. Now the BMW disc can be fitted on Marina hub. To fasten it I cut Marina discs in pieces. Marina disc has a thick flange where the bolts are fastened. I cut the flanges off and cleaned the remaining flange. This left me with circular disc with threaded holes. Now it is simple job to fit the BMW disc to Marina hub with longer 3/8 UNF bolts. See photos.

Caliber brackets were machined from 11 mm steel plate.

I was going to fit Marina rear axle but was not convinced about its long term reliability. Luckily I located a Triumph TR7 5-speed rear axle which is basically the same as Rover SD1. This axle would handle the V8 easily. Only problem was its width, about 5 inches too wide for Minor body. Solution: cut and weld. I took careful measurements and chose to cut the axle at the location where it rests on the leaf springs. I first cut and shortened on end. I used 4 feet long steel tubes bolted on both flanges to check the tracking. Once I was happy I welded the tube back together, smoothed the welds and checked the tracking both horizontally and vertically. After applying some heat I got the flange spot on. Then I did the same to the other end. After welding yet another check to make sure everything is correct.

TR7 rear suspension has coil springs and I had to fabricate new spring platforms and grind original ones away. I chose to retain the brackets for upper diagonal arms and use them on Minor. This gives additional support for rear axle. Halfshafts needed attention too. Luckily they are of different length, the other about 2,5 in longer. I could fit the shorter LH side shaft to RH side and only shorten the longer one about 5 inches. Well, not so simple. It turned out that the shaft was induction heat treated the whole length and about 4 mm deep so ordinary cutting tools would not work. Luckily I finally located a machinist who had correct tool bits and he could machine the new splines to hardened shafts. Now this shortened ex-RH side shaft is fitted to LH side. Diff was rebuilt and assembled with SD1 3.08:1 ratio and new bearings, seals and gaskets.

Since I use Triumph rear axle the natural choice would have been matching drum brakes. These needed a total rebuild and I have always liked disc brakes so I chose to fit rear discs to Triumph axle. Halfshaft flange diameter on this axle is 130 mm so first I had to find discs that fitted on the flanges and were not too deep. Peugeot front solid discs are 247 mm in diameter and 10 mm thick. Depth is 34 mm. Inside diameter is 66 but I enlarged it to 70 mm. Hub diameter on flange is 64 mm so I turned a pair of spacer rings to close the gap. See photos. VW Passat rear calibers were chose due to their size and inbuilt handbrake. These are fitted to caliber brackets machined from 11 mm steel plate.

I chose to fit Austin Metro master cylinders and pedal pox because the could be fitted vertically and were of compact size. Brake master cylinder has a integral servo. These were fitted to the modified bukhead. Brake pedals needed small modifications. An adjustable brake bias valve was fitted to the rear brake circuit. Handbrake handle is from an old Toyota and the cables are a mixture of Morris Minor and VW Passat.

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	Updated December 4, 2000.