Contents of the Jaguar V12 Dossier

Introduction.

Historical and Background

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1. Why a V12 – an assessment of the advantages and disadvantages of a V12 engine.
2. Historical Background – engine developments in the 1960s that would have influenced Jaguar designers and engineers in creating their V12 engine.
3. Brico Injection – the story of the electronic injection system originally intended for the V12 but which sadly was discontinued at a late stage forcing a change to 4 carburettors.
4. ECU changes for the TWR Group A racing XJS – how the Lucas 6CU injection system was adapted, first with simple changes, then with addition of a new circuit board.
5. Harry Weslake – a great character who made important contributions to Jaguar engines.
6. Jaguar Roots in Stockport – where it all started, long before Blackpool.
7. The Four Valve V12 Story – some background to the four valve cylinder head Jaguar prototypes and a later version tried briefly and abandoned by TWR.

Support and Advice.

8. V12 Vacuum Advance Files – a series originally published in Jaguar World detailing all the vacuum advance systems used on the V12.
9. Exhaust Over-axle Mounts – a guide to the variations of mounts and their positioning.
10. Over-run Valves and Cutoff – an explanation about an important but often misunderstood topic with relevance to manual transmissions.
11. Idle Adjustment – Lambda 6CU, 16CU, etc. – a guide to idle adjustment of V12 engines with Lambda feedback.
12. Lambda Sensors – an explanation about different types and how they work and why they might fail.
13. Spark Plug Thread Friction – guidance for avoiding seizure problems with taper seat long life spark plugs.

Technical.

14. Early Days of Emission Control at Jaguar – how the topic grew from the original US requirements for the 1968 4.2 E Type.
15. Exhaust Emissions and the Jaguar V12 – arriving just as emissions regulations were gathering pace, Jaguar had to keep the V12 compliant in the face of ever tightening legislation.
16. Air Injection – why it is used and how it works.
17. The V12 Structure – assessing the open deck construction and many other details.
18. Cylinder Head and Combustion Chamber – charge motion, flame propagation, squish, the change from flat heads to HE.
19. Cams and Tappets – a detailed examination of the V12 valve operating mechanism and racing developments.
20. Valve Seat Security – why valve seats sometimes come loose and what can be done about it. Also the reality about valve seat recession and unleaded fuels.
21. The Crankshaft – details of the design of this important component, featuring the oil ways, balance and vibration issues, and how it was made.
22. Rear Main Oil Seal – the story behind solving a rather difficult sealing problem, first with a rope seal then with a lip seal.
23. Connecting Rods – H section or I section and other considerations.
24. The Timing Chain and Tensioner – a simple and mostly reliable camshaft drive and the tensioner with virtues and frailties.
25. The Oil Pump and Lubrication System – the reasoning behind the unusual crescent type oil pump and the change from relief flow cooling to full flow.
26. Hot Air, Pumping Work and Heat Losses – how the system losses affect performance.
27. Ceramic Coatings on Pistons, etc. – experiments to reduce friction and thermal losses.
28. Balance Pipes – explanation of why they were widely used with multiple carb induction systems.
29. Induction Systems and Inlet Ports – the build-up of knowledge in this area leading to the V12.
30. V12 Air Intakes – the real significance of intake size and air temperature.
31. It’s not just about Flow – the importance of resonant pulsations in the induction process.
32. Obscure Ignition System Issues, not just V12 – magnetos, HT leads and interference, early Lucas electronic racing system, capacitor discharge, etc.
33. Detonation, Octanes and Ignition Timing – avoiding damage when chasing performance.
34. Musings about the Jaguar V12 – why the production V12, including the HE, was actually rather disappointing in terms of the usual yardstick of b.m.e.p. and how this was reflected in fuel mapping and efficiency.
35. Jaguar V12 ECUs – Types, part numbers, applications, interchanges, brief comments.

General Interest.

36. May Combustion System Alternative – an internal memo by the writer about an alternative method.
37. The Butch Test – an explanation of a rather brutal engine test procedure.
38. The Rare and Exceptional 1980 XJS – a description of this rare model with the desirable 10:1 compression ratio variant of the V12 engine, also used in a small number of XJ12 saloons.

Oddments.

39. GTM – a little mid-engined kit car based on the BMC mini engine and running gear, which the writer was deeply involved with in the 1960s.
40. The Garden – somewhere to relax away from engineering yet still with a Jaguar V12 connection