MGB Special Tuning p.455 - Suspension Tuning, Road Spring Rates & Competition Parts
Reference · 1962-1974 BAll 6 data & spec plates
MGB Special Tuning data: lightened flywheel part CAHT 86 (16.5 lb), steel timing sprockets, oversteer/understeer factors, fly-off handbrake parts and a competition ignition coil table.
Part of 1962-1974 MG B Data & Spec Plates
This is page 455 of an MGB competition/special tuning reference. It covers a lightened flywheel (C-AHT 86, 16¾ lb.), steel timing chain sprockets for high-rpm use, and an extensive Suspension Tuning section explaining understeer and oversteer with numbered lists of factors that promote each. A Road Springs section explains spring rate and working load, followed by a table of nine coil and leaf spring part numbers (AHH 6451, AHH 5789, C-AHT 21, AHH 7080, AHH 6453, C-AHH 8343, AHC 31, AHH 7346, C-AHT 20) with rates, working loads, deflections and fitted heights, plus footnotes on MGB Tourer/GT applicability by car number. Anti-roll bar options (9/16 in., 5/8 in., 3/4 in.) with part numbers and installation kit C-AJJ 3306 are listed, along with competition shock absorbers and stiffer valve assemblies. The right column covers Dunlop tyre advice, the Stage 4 distributor (C-BHA 4415, Lucas 40943A), Champion spark plug grades (N-9Y, N3, N62R, N57R), dynamo pulley notes, free-flow exhaust manifold (C-AHH 7103), fly-off hand brake conversion parts, Sebring Perspex headlamp cowls (C-AJJ 3307), and detailed instructions for baffling or deepening the engine oil sump for 18G/18GA and 18GB engines, including modified sump and packing-piece part numbers.
Is this accurate? Sign in to help verify it.
Frequently asked questions
- What road spring rates were available for the MGB?
- Coil springs: AHH 6451 (348 lb./in., 1030 lb. working load), AHH 5789 and C-AHT 21 (480 lb./in., 1193 lb.). Leaf springs: AHH 7080 (93), AHH 6453 (99), C-AHH 8343 (100), AHC 31 (99), AHH 7346 (124), and C-AHT 20 (124 lb./in.).
- What anti-roll bars are listed for the MGB and what part numbers?
- 9/16 in. (14·3 mm.) AHH 7329 (2 off bearing AHH 6541 also required), 5/8 in. (15·9 mm.) C-AHH 7593 (includes bearings), and 3/4 in. (18 mm.) C-AHH 7924 (includes bearings and locators). Installation kit C-AJJ 3306 is required if the car had no anti-roll bar previously.
- What factors tend towards understeer on the MGB?
- Stiffer front springs; fitting a front anti-roll bar or increasing its diameter; lowering the front suspension (premature contact of front bump stops); increasing rear tyre pressure above recommended figures; decreasing front tyre pressures (must equal at least recommended figures).
- What spark plugs are recommended for competition MGB use?
- The standard plug was Champion N5, now N-9Y. For competition, N3 is recommended; if a colder grade is needed, use N62R or the colder N57R.
- What is the Stage 4 distributor for the MGB?
- Part No. C-BHA 4415 (Lucas 40943A with 32-oz. spring). It has no vacuum advance; automatic advance is 24° crankshaft degrees, giving 30° maximum with a 6° B.T.D.C. static setting.
- How is the fly-off hand brake conversion done?
- Fit pawl C-AHH 7223 and operating rod C-AHH 7222 for early cars, or C-AHC 551 from Car No. 115596 and on all GHN/D-4 cars.
No comments yet.