Extractors

When I test drove the E21 earlier in the week, I noticed that the steering linkage was binding on the exhaust I made for the car. As a result, I decided it was time for the temporary exhaust to go - and dug out the sacrificial extractors from the parts bin.

Some photos of the existing setup for those who don't remember or hadn't seen it, a standard cast iron manifold (stock part from EA-AU I6 even in XR6 form) along with a rudimentary J section to get it past the steering arm.

The dismantling begins! I thought at first I might be able to get away with retaining one of the collectors but alas, on a falcon the steering arm goes on the outside edge of the engine bay and the collector/exhaust hug tight to the engine and run to the engine side of the steering. Not so in this case due to space constraints.

Cleaning up the cuts ready for re-welding with a flaps wheel (outside) and wire wheel on a drill (inside)

Collectors mocked up into place, clearance on all sides and angle of ingress/egress determined.

A fully dismantled set of extractors to start with.

Here I've used some concretors reinforcement bar to fix the collectors and flange together in 3D space before removing it from the bay. This allows me to work out where I can and can't run pipes and also gives me an outside dimension from measurements I've made.

Shaun helps to clean the outside of some donor pipe from the original extractors using the flaps wheel on the grinder.

Mocking up and tacking in place the extensions to the original pipes. For almost all runners, the original pipes were used in place, except cylinders 4 and 5 which were transposed.

Clamping cyl 2 runner in place to determine positioning for Cyl 3 (which is then tacked as per the image)

Cyl 2 tacked.

Gaps bridged

Cylinder 4 and 5 tacked into place, Cylinder 6 now has a pipe connecting it to the flange.

Here I've made a connection for Cylinder 5 - this was the most difficult part of the whole process as the Cyl 6 curve is very tight to this join.

Test fitting, it had a bit of trouble at first around the alternator wiring, clutch cable and hydraulics for the power steering; later I relocate these to the top of the brake bracket.

A shot of the inside of the collectors

Cutting the tacks to Cyls 1, 2 and 3 for finish welding on the collectors (both banks).

They warped a little during finish welding but a bit of reo-bar as a lever soon sorted that. Here they are with the temporary reo-bar removed also.

Here you can see I've moved the hydraulic lines for the steering to the other side of the steering linkage for better clearance.

I've also moved and secured the clutch cable and other hoses out of the way.

Secondaries added - I taped nuts to these pipes to give clearance under the car to the floor, then held them up in place and tacked them on the car. A little hard to remove due to the distance between the ends (side to side) as a result of the cross-over (getting them to turn 90 degrees)

Here's a video of how it sounded at this point.

Started making a joiner. Turns out I used the wrong sized pipe (4") so it was never going to fit properly; it was later cut down to fit.

Cutting and bending the pipes to flatten them out and get them closer together to make it easier to put them in the car and so the collector can be made.

Cutting like this allowed the pipes to be opened out to more of an oval shape

Welded on the inside while I can still get to it.

Tacked on the outside before test fitting; always test fit before finish welding something like this!

Here you can see I've welded a peice of reo-bar to the setup when test fitting under the car, the reo bar marks the centreline of the pipe and is pressed up hard against the floor to ensure clearance.

Pieces of the 4" pipe cut up and in place.

Fitted then trimmed to fit up to the flange from the original extractors.

Joined to the flange and then finish welded. Test fit under the car proved perfect.

Here's a video showing the sound coming straight from the rear collector.

Angle of egress from the collectors into the secondaries.

The connecting pipe (formerly the de-cat pipe from my falcon) needed to be curved slightly to fit into the new exit location (this location has better ground clearance than previously)

Tacked with reo-bar with flanges bolted to both parts of the exhaust and bends finalised. Note that the cuts do not go all the way around the pipe, this makes it much easier to handle and bend neatly

Finish welded.

I moved the car to sweep the shed and managed to snap the connector off the oxy sensor wires with the brake linkage. Here I've cut out, bent slightly and re-welded the oxy sensor mount for clearance.

Cleaning up the extractors with a wire wheel is fast, but very dusty, has lots of vibrations, and occasionally you get impaled or pelted with bits of wire. I modified my failed cigweld auto mask as a face shield as it was too painful just using a regular pair of goggles.