Fitting the Janspeed 4-2-1 Manifold

Congratulations! You've found the most comprehensive, hands-on, step-by-step guide to fitting the Janspeed 4-2-1 Exhaust Manifold to the Elise on the net.

I'll take you through the fitting sequence for the Janspeed 4-2-1 Manifold step-by-step ... follow these and you'll be fine. If you intend to fit an alternative performance manifold then most of this guide will be applicable, but of course I cannot help you on specific differences.

Note that the sequence described would be the way I’d tackle it if doing it again, not necessarily the order I took whilst learning!

If you intend to fit heat wrap to your manifold, do it whilst the manifold is out of the car (it’ll be so much easier!). I didn't fit heat wrap, so can't offer any advice on this subject.

Precautions

I strongly advise you wear eye protection (glasses or goggles) when working beneath the car. When removing the exhaust manifold and separating the various parts rust particles will fall to the ground, and into your eyes if unprotected. Fibres will also fall from the heat shield material when it is disturbed; protect your eyes from this too.

What you need:

1. Janspeed Stainless Steel 4-2-1 Exhaust Manifold and Flexi Section, Part Number SM999 / SM999LP.

Available from Janspeed, £382.97 exc. VAT & P&P;

2. Exhaust Manifold Gasket, Rover Part Number LKG100300.

Available from your local Rover dealer, £4.25 exc. VAT & P&P;

3. Catalytic Converter Gasket, Rover Part Number WCM100480.

Available from your local Rover dealer, £0.70 exc. VAT & P&P.

Note: You'll need two if you completely remove the Catalytic Converter;

4. Exhaust Manifold Flange Nuts (x 5), Rover Part Number FX110041.

Available from your local Rover dealer, £0.68 each exc. VAT & P&P;

5. Copaslip (100g tube).

Available from Race Speed, £1.95 exc. VAT & P&P;

6. Stainless Steel 6mm Nut (for when we've modified the Alternator Heat Shield).

Available from Aerotek, Part Number M6NC, £0.06 each exc. VAT & P&P;

7. Stainless Steel 6mm Shakeproof Washer (for when we've modified the Alternator Heat Shield).

Available from Aerotek, Part Number CRW6C, £0.40 each exc. VAT & P&P;

8. Cable ties (various);
9. Drill and 7mm metal drill bit;
10. Steel Rule and Scriber;
11. 5mm Hex bit socket / hex key (for undertray retaining screws);
12. 10mm, 13mm, 15mm and 17mm Spanners / Sockets, short / long extension bars, ratchet handle;
13. 19mm Socket (for engine steady bar, if required);
14. 22mm crows foot spanner (for Oxygen (O2) Sensor);
15. Small square profile file;
16. WD-40;
17. Wire brush;
18. Hacksaw;
19. File;
20. Soft Faced Hammer (for shaping Alternator Heat Shield);
21. Vice and metal surface for metal shaping;
22. Jack & Axle Stands (x 4);
23. Oil Filter Remover;
24. Eye Protection (glasses or goggles);
25. Clean rags;
26. Engine Oil (your choice, I use Castrol GTX magnatec).

1 litre is ample if only to 'top-up' loss from oil filter removal;

27. About eight hours of time.

 

Optional (if replacing oil filter):

28. Oil Filter, Rover Part Number LPW100180.

Available from your local Rover dealer, £5.51 exc. VAT & P&P.

Step 1: Raise the Car

Raise the car by following Step 2 in the Race Exhaust fitting guide.

Step 2: Disconnect Oxygen (O2) Sensor

Disconnect the plug and socket connecting the engine wiring loom to the Oxygen (O2) Sensor lead. The multiway plug and socket is located on a plate bridging two water pipes just below the Rear Timing Belt Cover (nearside end of the engine). Turn the connector through 90 degrees and use a screwdriver to lift the securing clip so that the plug can be pulled from the socket. Use a wire cutter to break any cable ties securing the Sensor cable to the rubber water hose (mine had two).

We will relocate this plug and socket, so now remove the socket by sliding a screwdriver under the socket retaining clip, pulling the socket from its plastic mounting. Finally, remove the plastic mounting by pinching the tabs on its securing lug together, enabling you to pull the mounting away. Put it in a safe place until later.

Step 3: Remove the Diffuser and Undertray

I found it easiest to leave the two button-head screws until last so that I could support the Diffuser for safe removal.

Step 4: Make Life a Little Easier (WD-40)

Spray WD-40 liberally on the three nearside Catalytic Converter screws (or studs if you still have them), the five Exhaust Manifold / Head securing studs / nuts, the four Exhaust Manifold / Downpipe studs / nuts, and the Oxygen (O2) Sensor where it enters the Exhaust Manifold.

Now go and have your first cup of tea!

Step 5: Disconnect the Catalytic Converter

Remove the three nearside Catalytic Converter nuts / washers / screws (or the stud retaining nuts) using a 17mm socket. If this is the first time these components have been disassembled, be prepared for some difficulties! Now would be a good time to replace the studs with stainless steel alternatives. See the Stainless Steel Cat Bolts guide for details. Discard the Catalytic Converter / Exhaust Downpipe gasket.

Step 6: Create Space behind the Exhaust Manifold

Note: depending on year of car the heat shield arrangement may vary from that described.

First some words of comfort. Although this Step is wordy, it's actually quite simple, so don't panic!

Remove the Main Heat Shield from behind the manifold. You’ll need a 10mm spanner to remove the nuts and hex head screws. Note the order of assembly. For the upper two hex head screws, the screw passes through (from the engine side): a) large washer; b) heat shield (engine side); c) mounting bracket; d) shakeproof washer; e) nut.

For the lower two hex head screws, the screw passes through (from the bulkhead side): a) washer; b) mounting bracket (bulkhead side); c) heat shield (bulkhead side); d) large washer; e) shakeproof washer; e) nut.

Next remove the Alternator Heat Shield. There is a hex head screw plus washer (13mm socket) securing it via a bracket to the head, plus two smaller hex head screws (8mm socket) securing it to its Mounting Plate on the engine block.

Remove the Main Heat Shield Mounting Brackets from the bulkhead wall by removing the locknut and washer using a 10mm spanner. This is a precautionary step so that you don’t accidentally knock them (then bend them or damage the securing screws) when removing / refitting the manifold.

Step 7: Remove the Exhaust Downpipe Flexi Section

The Exhaust Downpipe Flexi Section is now free, remove from the working area (ready to sell it on eBay!).

Remove and discard the Exhaust Manifold / Downpipe Flexi Section gasket.

Step 8: Remove the Exhaust Manifold

This is secured using five flange nuts onto studs screwed into the Cylinder Head. Using a 15mm spanner / socket, you may find the studs come out with the nuts. If so, you’ll need to clamp the unthreaded part of the stud in a vice to remove the nut. Clean the stud thread with a wire brush for refitting later. Note the absence of WD-40 on the studs in the photo - Doh!

Lift the manifold out from above.

Remove the Exhaust Manifold / Head gasket.

Step 9: Remove the Oxygen (O2) Sensor from Manifold

This can be a real pain, or not so bad, depending on the condition of your Exhaust Manifold. A large 22mm crows foot spanner with some crafty footwork undid mine. I’m sure the WD-40 spayed on some time ago helped a lot. Use a wire brush to clean the thread on the Sensor, and gently clean the Sensor body itself.

Step 10: Fit the Janspeed 4-2-1 Manifold

Refit any manifold studs into the Head by first coating the thread with anti-seize copper grease ('Copaslip') and then screwing it into the Head as tight as you can with your fingers.

Now coat all the protruding stud threads with 'Copaslip' and place the new Exhaust Manifold gasket onto the studs (note: metal side is on the outside).

Carefully feed the Janspeed 4-2-1 Manifold from beneath the engine, and suspend on the studs. Take your time, by judicious manoeuvring it will fit!

Fit new flange nuts onto the studs and tighten them down. I was unable to find the torque setting, so went for 'tight' but not 'grit teeth and use long lever tight'. Bruce (Ragtop Roadsters) goes for 50Nm. This MGF site goes for 45Nm. Either way, it's not given in the Elise Workshop Manual ('Service Notes')!

Option: Take a look at Step 13 to decide whether you want to refit the Alternator Mounting Bracket using its upper hex flange screw unmodified by fitting it before tightening down the Manifold flange nuts. Note that this will probably mean that you will have to remove the manifold in order to remove the Alternator Mounting Bracket again in the future (should you ever need to).

Step 11: Fit the Janspeed Flexi Section

Slide the silicon mounting bush over the Flexi Section hanging bar and refit the Flexi Section to the underside of the car, remembering the order of the components detailed in Step 6 above. Don’t tighten the hex screws yet; allow some slack so that the Flexi Section can move around.

Push the end of the Flexi Section over the end of the 4-2-1 Manifold, making sure that the Catalytic Converter mounting is correctly aligned. You need to get the raised lip of the Flexi Section pipe as close to the corresponding raised section on the 4-2-1 Manifold as possible. I used a soft-faced hammer to help knock the two ends together. This will allow the Clamp to bridge over the two lips.

Tighten the Janspeed Flexi Section to 4-2-1 Manifold Clamp, using a 16mm socket. Ensure that the Clamp bridges the lips of each end of the pipes so that, as you tighten the Clamp, it brings the two sections together.

Step 12: Modify the Alternator Heat Shield Mounting Bracket

In order to refit the Alternator Heat Shield we need to modify it and its Mounting Bracket. This is because the new Exhaust Manifold obstructs the upper section of both these parts.

Reposition the Mounting Bracket against the engine block to determine the amount of alteration required. I had to remove the upper corner, using a hacksaw to remove the main waste then shaping and removing the sharp edges with a file. This resulted in the loss of the upper heat shield mount nut (the one that's welded to the mount), so we'll tackle this next by creating a new mounting point.

Working away from the car, align the lower Alternator Heat Shield Mounting hole with the corresponding nut location on the Bracket. Use a scriber to mark a cross on the Bracket 60mm above the centre of the nut, the same distance in from the edge as the centre of the nut. Drill a 7mm hole at this point. Align the lower Alternator Heat Shield hole again, mark and drill through a corresponding new hole.

Step 13: Modify the upper Alternator Heat Shield Mounting screw

Step 14: Refit the modified Alternator Heat Shield Mounting Bracket

Step 15: Modify the Alternator Heat Shield

The upper right-hand corner of the Alternator Heat Shield needs to be modified so that its profile matches that of the Exhaust Manifold.

Place the Alternator Heat Shield into its fitted position and mark the area that comes into contact with the Exhaust Manifold. Use a soft face hammer to reshape this area so that it curves out towards the bulkhead, instead of the fold that comes towards the Exhaust Manifold. Take your time, returning the Alternator Heat Shield to its mounting location to check progress, until it can be placed against its mounting points without touching the Exhaust Manifold.

This worked perfectly for me! If you find it too difficult or you're not happy with your end result you could always buy the EliseParts.com Alternator Heat Shield, but you won't need to, will you?

Step 16: Refit the modified Alternator Heat Shield

Refit the modified Alternator Heat Shield, remembering the order of the components (see Step 6 above).

Use a Stainless Steel 6mm Shakeproof Washer and Nut to secure the Alternator Heat Shield at the new hole, using the original hex screw.

Step 17: Refit the Main Heat Shield

Refit the Main Heat Shield Mounting Brackets to the bulkhead. Don’t tighten the locknuts yet, allowing the Brackets to slide in their grooved slots.

Refit the Main Heat Shield, remembering the order of the components (see Step 6 above).

Tighten the Main Heat Shield Mounting Bracket nuts that secure the Brackets to the bulkhead.

Step 18: Replace the Oil Filter

Clean the Oil Filter Adapter mating face and smear a coating of engine oil on the Oil Filter rubber sealing ring. ‘Prime’ the Oil Filter with engine oil by half filling it. Screw the Oil Filter onto the engine Oil Filter Adapter by hand, just sufficiently to make a firm seal, typically 2/3 to 3/4 of a turn after the Oil Filter sealing ring has made contact.

Top-up the engine oil as required.

Step 19: Replace the Oxygen (O2) Sensor

Apply 'Copaslip' to the Sensor thread. Screw into the hole at the end of the 4-2-1 Manifold and tighten using a 22mm crows foot spanner. You’re aiming for a torque of 55Nm. Ideally you should fit a new compressible sealing washer first, but I didn't as I didn’t have one!

Now we will re-route the wiring. Looking up into the rear of the engine bay, just below the Coil Assembly, you will see there is a free hole (5mm or so) in the chassis cross-member (on its outer lip). Take the connector plastic mounting (from Step 4 above) and, using a small file (a small square edged file is best), open this round hole up into a square shape sufficient to accept the plastic mounting lug.

Route the engine loom Oxygen (O2) Sensor socket down behind the engine to this location. Orientate the connector plastic mounting so that it accepts the socket such that the open face of the socket is towards the offside of the car (i.e. no twists or loop in the cable). Push the connector plastic mounting lug up into the newly created square hole, then secure the socket to the mounting by sliding it home.

Route the cable from the Oxygen (O2) Sensor so that it is clear of the offside drive shaft, and push the plug into the socket, making sure its securing clip is engaged.

Use a cable tie to secure the Oxygen (O2) Sensor cable in place. I used a hole in the lower offside edge of the Coil Assembly Mounting Plate to accept the tie and fix the cable in place.

Step 20: Checks

Ensure all tools etc. are removed from the working area. You should have the following left over:

• Exhaust Manifold (with four studs in downpipe flange);
• Exhaust Downpipe Flexi Section;
• Exhaust Manifold / Head gasket;
• Exhaust Manifold / Downpipe Flexi Section gasket;
• Flexi Section / Catalytic Converter gasket;
• Nine locknuts;
• Anti-tizz bracket and two hex screws (if applicable).

If you have more, or less, something isn’t right!

Lower the car.

Start the engine, check that everything is OK (no exhaust blowing or oil leaking from the Oil Filter?). If not, let things cool down, raise the car again and tighten the offending item and retest. If everything is OK, you’re almost there!

Step 21: Finish

Re-raise the car and refit the Engine Bay Undertray and Rear Diffuser.

Lower the car.

Recheck the engine oil level and top-up as necessary.

CONGRATULATIONS!