Opel Manta A series Turbo Build Sheet

The technicians at Broadspeed who converted the cars from standard to Turbo specification used the following set of instructions:

1. Remove engine: (retain engine oil and coolant for re-use)
   

   a.	Remove sump; fit oil drain union using template, paint sump.
   b.	Remove cylinder head, fit new valve springs, taking care to replace valve stem oil seals correctly. Paint cylinder head and rocker cover.
   c.	Remove pistons; fit low compression pistons correctly graded and fit special big end bearing shells.
   d.	Refit cylinder head with special gasket. Paint cylinder block.
   e.	Refit sump. Mark timing on crank pulley.
   f.	Remove clutch pressure plate and replace with competition pressure plate, using special 1.6mm spacers

2. Modify R.H. Chassis rail to template - prime and paint.
3. Fit fuel pump mounting bracket to crossmember - prime and paint.
4. Remove petrol tank filler neck, bronze in fuel return tube and re-fit filler neck.
5. Install fuel return line using ‘P’ clips and STEEL pop-rivets or PK screws.
6. Fit fuel pressure regulating valve - connect up fuel return line.
7. Mount dump valve on R.H. flitch panel.
8. Refit engine - ensuring that engine mounts are correctly settled.
9. Install high pressure fuel pump and pipe to mechanical fuel pump and fuel pressure valve, ensuring that the pipes do not touch bodywork or brake lines.
10. Fit exhaust and intake manifolds using Loctite 602 on the bolts.
11. Replace carburettor mounting studs with special studs, using Loctite 602.
12. Fit oil feed and oil drain unions with sealing washer using Loctite 602. Slacken turbo centre clamp and compressor housing screws. Mount turbo on manifold studs with gasket, starting the threads on both ends of the oil drain pipe at the same time. Fit plain washers and stainless nuts to the exhaust manifold studs using Loctite 602 and tighten. Tighten the unions on both ends of the oil drain pipe and then tighten the turbo centre clamp. Position the compressor housing and tighten the clamping screws.
13. Fit the oil pressure union and transmitter to the oil gallery thread in block, using sealing compound on the threads and ensuring that the transmitter lies at the right angle. Fit the turbocharger oil feed pipe to the union and route along the cylinder block to the turbocharger. Prime the turbocharger bearings with 2 oz engine oil and connect the feed pipe to its union immediately before cranking up the oil pressure prior to starting the engine.
14. Bolt the exhaust flange to the turbo with 3 bolts and position the exhaust primary pipe with the jig. Tack weld to the flange; remove both pipe and flange, weld pipe to flange. Bolt exhaust primary pipe in position with gasket, using special stainless bolts and spring washers with Loctite 602.
15. Remove exhaust system and remove baffle from centre silencer. Modify exhaust front pipe to suit primary pipe and refit exhaust system, taking care that it hangs correctly and no fouls can occur. Fit support bracket and clamp between the primary pipe and bellhousing.
16. Fit the oil cooler kit, mounting the cooler on rubber mounts and routing the pipes correctly.
17. Modify the radiator grill and R.H. headlamp surround as per template and fit the turbo cooling duct, using P.K. screws.
18. Mount the air cleaner unit in position and fit the ducting to the dump valve and compressor inlet
19. Strip the carburettor and modify the jet settings according to the carburettor specification. Change the throttle linkage to the mechanically operated secondary choke, ensuring that the butterflies open smoothly and close completely. Fit the special carburettor cover together with the damped float and special needle valve and fuel inlet union.
20. Remove the throttle operating cam from the original spindle and bronze to the new spindle using the jig to obtain the correct position.
21. Modify the throttle cable bracket and mount on the inlet manifold.
22. Fit the throttle spindle seal to the airbox and fit the two bulkhead fittings. Fit the throttle operating spindle, using moly grease and fit end float shims and the roll pin to give an endfloat of ¹/₁₆", ensuring the roll pin clears the base of the airbox when the spindle is rotated.
23. Assemble the airbox and carburettor together on the inlet manifold, ensuring that the roll pin engages with the fork in the throttle lever, and the gaskets are correctly positioned. Fit the carburettor retaining nuts using Loctite 602. Fit the fuel pipe between the carburettor and bulkhead fitting. Connect up the throttle cable and return spring, ensuring full opening and closing of the throttles.
24. Fit fuel and boost pipes between the fuel pressure valve and air box via the correct routes.
25. Fit the boost pressure duct from the turbo compressor outlet to the airbox.
26. Fit the choke wire and union to the airbox, connect the terminal to the choke terminal and install the resistance.
27. Remove the distributor, strip and remove the centrifugal advance mechanism, refitting the springs such that the cam is retained in the retarded position. Refit the distributor and set the static ignition timing to 20^o B.T.D.C.
28. Fit Bosch W200 T35 Spark Plugs.
29. Install boost gauge, oil pressure gauge and clock in correct position in the auxiliary instrument panel and mount the panel taking care that it is square with the fascia. Install auxiliary instrument panel light loom and feed wire loom. Ensure that all connections are properly insulated.
30. Install the boost gauge/fuel pressure valve pipe; ensure that the grommet through the bulkhead seals properly.
31. Wire up the fuel pump, connecting the feed wire to fuse no.4. Change fuse to 16A.
32. Set the clutch adjustment according to workshop manual.
33. Fit engine breather hose between rocker cover and air cleaner, using ‘P’ clips and PK screws. Fit blanking grommet to small breather hole in rocker cover.
34. Remove lower attaching bracket from front overrides. Fit front spoiler, positioning as accurately as possible to give a good fit-paying particular attention to the centre join. Drill fixing holes through lower end of the front overrides into the apron and retain with PK screws.
35. Set fuel pressure to 4 psi. with master gauge.
36. Prime the turbocharger bearings with 2ozs. engine oil and fit the oil feed pipe to the turbocharger union.
37. Crank up oil pressure.
38. Start and warm up engine to normal working temperature. Set tappets with engine running using the timing chain splashguard.
39. Connect Sun Tester and set points dwell angle. Re-set ignition timing to 20^o B.T.D.C. with strobe.
40. Set up carburettor as follows:-
    Screw idle air bleed screw fully in throttle stop. Adjust CO reading to 4% with mixture screw and set idle speed to 700 rpm on the screw. Screw out idle air bleed screw and simultaneously adjust idle mixture screw to maintain a CO reading of 4 ¼, such that the idle speed is 800 -850 rpm, with the air box cover placed in position. Set the throttle on fast idle speed to 2700 rpm.
41. Fit air box cover with gasket and attach label with adhesive.
42. Fit mixture control screw access plug to air box. Fit hose between air box and dump valve.
43. Check all fluid and oil levels.
44. Fit alloy road wheels and balance.
45. De-wax car and clean all window.
46. Fit body-lining tape.
47. Fit registration plates and tax disc.
48. Set tyre pressures.
49. Check that all lights, instruments and controls function correctly.
50. Carry out rectification work in conjunction with road test report.
51. Thoroughly clean car inside and out.

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