Heated seats part 3 - wiring

The supplied relays were fixed to the transmission tunnel behind the seats, using self tapping screws over the carpet.

Relay fixed to the transmission tunnel

The transmission tunnel carpets were lifted along the edge near the floor. The wires were then fed along this area towards the front of the car and up to the central under dash tray.

Wires routed under the carpet, against the transmission tunnel

The earth wire was attached to the ground point on the chassis.

Ground point on chassis

The supply and ground wires were both extended.

Wires extended and tie wrapped in place

20mm holes were drilled in the under dash trays near to the heater outlets. The switch wires were disconnected from the loom and fed through the tray and clicked in to place. They were then reconnected to the looms.

The supply (live) wire was connected to position 3 on the ignition switch, so that the seats only operated when the ignition was on and would not drain the battery if left switched on.

So now to test. Without the ignition switched on, there were no lights on the switches in any position - so a good start! Next the ignition was turned on. A green light when the switch was set to the low setting. A red light when it was set to maximum. And no light at the off/central point - great news.

Now I just need to test it in anger.

Edit: Been out in the car today (Thursday) and the heated seats really work. Brilliant!

Heated seats part 2 - the heaters

The heated seats kit has arrived, along with the staples.

The kit

Unfortunately the instructions are in German! But the company who produced them were very quick with a response to an email and a link to an English version. The wiring diagram was fine and understandable, but I was concerned that there was something hidden in the wording.

First the pads were detached from the loom. The pads were fixed to the foam base and back of both seats using the double sided tape fitted to the pads.

Heat pad in place

This was easy for the base, but I needed to remove more staples from the side (bolster) leather to allow me to get my arm up the back. The latter proved a bit tricky to remove the film from the sticky tape when in place! However, once done and pressed firmly in to place it appears very successful and can't be seen from the outside. Next the leather seat covers were stapled back in place using 8mm staples.

A 16mm hole was drilled in the lower back at the centre and the wires from each pad fed through. An extra layer of tape was wound round the wires, to avoid chaffing, and these were then taped in place facing the transmission tunnel.

The wires at the base of the backrest

A 16mm hole was drilled in the lower back at the centre and the two pad wires were fed through. An extra layer of tape was wound round the wires to reduce the risk of chafing. The wires were made to face the transmission tunnel and taped over. The fixing rails were re-fitted using the original cap head bolts, before the seats were cleaned with leather conditioner. Done.

Seat looks like it did originally

Head restraints - liberating space

The head restraints supplied by GD restricted how far back the seats could be pushed back. So to address this I modified them! Now I have an extra 40-45mm of travel in the seats.

The head restraints were removed from the seats. The head restraint was placed on a flat surface upside down and by putting a metal ruler against it, a line was marked in chalk 150mm up (so 150mm from the top).

Line in chalk 150mm up

Next the sides were marked in chalk. These side lines were marked from the line across the back parallel down to the metal location bars and finished about 12mm behind the bars (you can see how much will be removed).

Line in chalk across side

The leather cover was then removed by releasing the Velcro and then compressing the foam of the head restraint, taking care not to rub off the chalk lines. The measurement/markings were then transferred on to the head restraint leatherette. The three pieces of Velcro were removed from the cover and retained for later use. I turned the cover inside out and then unpicked the sewn seams at both sides from the bottom up to the line that went across the head restraint. There were two rows of stitches (a hidden seam stitch - black in my case and a top stitch - red for mine). The threads were then knotted on the reverse and a covering of contact adhesive applied. These two actions should stop the stitching unravelling further. The leather cover was put to one side.

Leather head restraint cover removed

The surface of the leatherette head restraints were then cut downwards from the line drawn to about 12mm from the head restraint location bars underneath. It was then cut across just above the bottom roll (leaving a lower flap for glueing). This formed an H shape cut (see photo below).

Leatherette cut in H shape on head restraint

The leatherette was lifted from the foam underneath. The foam that protruded was removed (try a hacksaw to get a smooth surface, but watch you don't cut any leatherette), as was any residual foam still attached to the leatherette of the back, bottom and side flaps. The top flap had about 5mm removed from the across the bottom (the exact amount can be established by pulling the leatherette tight and marking a line across the flap over a flat area of the head restraint, to remove any excess). The side flaps were carefully thinned, then the top flap was thinned for a strip about 12mm deep across the width. The side flap (a triangle) was marked on the reverse of the top flap and this too was thinned.

Head restraint being operated on!

Contact adhesive was applied to the foam, the reverse of the bottom flap, the reverse of the top flap including the thinned area, the reverse of the thinned side flaps, the leatherette faces of the side flaps, the leatherette face of the lower flap (about 10mm across the width). Once touch dry, the bottom flap, followed by the side flaps were pressed in to place. Finally the larger top flap was pressed in to place on to the foam.

The cover was fitted over the head restraint and the new position of the Velcro marked with chalk. The cover was removed, then the Velcro was glued and machine sewn in place. The stitching was redone by hand, down 45mm below the chalk line - both the seam and the top stitch. The remainder of the seams were simply top stitched for continuity. Finally, after refitting the cover again, it was tightened in place, using the Velcro. The remaining bits at the bottom corners were glued in place to make a neat job.

Head restraint in place liberates about 40mm of extra seat travel,

a further 70-75mm is available if the head restraints are not fitted.

The modified head restraints have removed a fair bit of the padding at the bottom back which touched the rear bodywork. This now allows the seats to be pushed back a further 40mm or so.

Heated seats part 1 - preparation

So living in the north where it is cold, I have decided to fit heated seat pads to my Cobra's seats. I had said a while ago that any future cars I had with leather seats would always be heated. But in my infinite wisdom decided not to bother for the Cobra - big mistake!

The heat pads for both seats were ordered from Amazon for just £58, including switches, relays and vat. This compares with a 2015 GD price list (which is all I had) at about £300 inc vat. I have decided to fit the switches to the under dash trays to avoid cluttering the dashboard. They have LED indicators showing that the heaters are off or on and at what setting. I may not be able to see the passenger side warning light from the driver's seat, but I should feel the driver's seat warm! This should remind me to check the passenger side.

First the seats were removed by undoing the four nuts and bolts that held each seat in place.

One of the removed seats

A seat base was removed from the seat. The base is held in place by Velcro all around and at the front the leather. I lifted the base from the back, pivoting it towards the front. I then found out that the front was also held in place by some glue, so I had to carefully detach it.

Velcro and glued area on front of seat base

I had expected the back rest to be the most difficult, so I explored this first. The leather was secured with staples at the base.

Staples at base of seat back

These were removed and to my delight the back leather was not stuck to the foam, so the pad can simply be fed up the back and attached with the sticky tape provided.

Next, the leather was released from around the back of the seat base. This Revealed that the leather was stuck to the foam! So I had to remove the staples from all around the seat base. This was a very time consuming process, because I didn't want to damage the leather. The Velcro was left in place on the base, but staples were removed where necessary.

Staples removed all around

Once all the staples that located the leather had been removed - loads of them, I tackled the delightful job of separating the leather from the foam. The leather was glued fully on to the top of the foam seat base. Once the leather was released, I scraped off the remnants of foam and lightly sanded this to remove any that I had missed.

Cleaned up seat base leather (reverse side)

To get to this point took me about 3 hours for one seat. Now for the other!

I have also ordered some upholstery staples to help me put it all back together, along with some contact adhesive.

When the pads arrive I will tackle the installation and wiring of them.

Electrical connections

Loom changes

Horn

These should ideally have been made before the loom was put in to the body, as it would have been much easier. On the column wiper and horn switch, there are a couple of changes to make.

First the horn relay (the third in) needs the purple loop removing.

Loop to remove can be seen here if you look carefully!

Loop removed

Earth added (see arrow)

Washer

The washer needs the green (or light green in my case) removing and replacing with an earth.

Earth wire (black) replaced green wire

Intermittent wiper

Then its the intermittent wiper. This needs more wires changing and a relay adding (VW 3BO955531 or 357955531). This has been ordered. It was easy enough to wire, although I did not have the correct colour wires, so used the correct gauge wire that I had and marked it up with the correct colour and the relay terminal. Refer to the GD diagram for wiring.

Changes made to wiring on column switch

Other connections

Now the bits that I hadn't done earlier!

The brake fluid warning wires on the loom had not been fed through the bulkhead or connected, so that was done.

brake fluid warning wires finally connected

Then it was pushing the fuel pump wire through the grommet at the top of the passenger foot well. Some Vaseline helped here. A new terminal has been ordered.

So hopefully that is the end of the wiring, assuming it all works! Now it is down to testing all the electrics.

Passenger seat

This was really easy compared to the driver's side. Basically I used the same process as on the drivers side, but did not have to worry about the handbrake. The seat belts were also added. Another job done.

Seat fixing - fitting to the car

Fixing the seats

This turned out to be a real pain and very time consuming - working out where to drill the holes to fix the runners. In the end I may end up changing the head restraints (which are currently mounted on the seat) to ones mounted on the roll over bars. Otherwise the head restraints touch the rear bodywork, the seat belts touch the head restraint and the head restraint restricts rearward seat movement - apart from that lot it is fine!

GD had supplied four fixing bolts, washers and spacers for each seat.  The long bolts and spacers go at the front of each seat. All the spacers were sprayed satin black to blend in (not that you can see them) and to reduce the risk of corrosion.

The carpets under the seats were turned back. Here I had to remove the seatbelt anchorages from the floor. A measurement from the rear bulkhead of 560 mm was used to locate the front fixing points on my seats, but check your own as Keith Akerman used 640 mm. The front hole nearest the transmission tunnel was about 75 mm from the tunnel side and about 90 mm away at the rear mounting point. A template of the bolt holes was used to determine the other location points.

Template taken from bottom of seat, marking the bolt holes

8 mm holes were drilled through the floor to take the fixing bolts. The holes I drilled in error (I had the runners in the wrong position), will act as drain holes!

The bolts were put loosely in the runners, before the seats were positioned in the car.

Bolts loosely fitted to runners

The seats were then trial fitted, before holes were cut in the carpet. Getting all four bolts through is not easy, so the rear holes were slightly larger.

The carpets were re-fitted with the seatbelt eye bolts. The holes in the floor were then marked with chalk and the carpet placed over them. The chalk was transferred on to the back of the carpet by pressing it with my fingers, before holes were cut in the carpet. Finally the seats were put in to the car and with the spacers at the front. The length of each bolt was noted, the seat removed and each bolt shortened to the appropriate length. The seats were fixed in place using the bolts, nylocs and penny washers from underneath the car.

Driver's seat fitted

Now just the passenger side to do.

Handbrake

Once the seat was in place, I could hardly get my fingers around the handbrake. I solved this by fitting a 3 mm spacer at the front handbrake mounting. Because the rear had no spacer, this caused the front of the handbrake to be move away from the car side and this created enough room to use it. Useful!!

Spacer between the handbrake and front mounting can be seen

The leather that covers the handbrake and the escutcheon were re-fitted.

Attaching the seat belts

I am fitting four point harnesses. I have had these in my Caterham and five point in my other two race cars. The five point were great in the race cars and stopped me submarining under heavy braking, but they could hurt the gentleman parts at times! So four point it was. You feel so secure with them on and they stop you moving about in the seat.

The harnesses are the clip in type in black to match the leather trim. It was simply a case of attaching them to the eye bolts on the fixings on the roll hoops and to the anchorages that I had located on the floor. The belts were then adjusted to suit me. At this point I took the opportunity to shorten one of the eye bolts so that it did not protrude from the fixing under the car.

4 point belts fixed

To keep the IVA inspector happy, I will edge the belt fixings with rubber trim to make sure that the curves are of sufficient radius.

Seat fixing - the runners

Runners

This is the easy bit!

Seat base as delivered

First job was to find the captive threads on the seat bases under the leather. The holes were found by finger and then a small indentation was made by pressing the leather over each hole. There were four of these - one at each corner. These were exposed by carefully cutting around the holes with a sharp craft knife.

Captive threads exposed

The threads needed running through with an M8 tap to clear the them. Eight bolts (M8) had been supplied by GD to fix the runners. One runner was fixed to each seat, making sure that the adjuster spring was nearest to the seat base (the runners are also handed). Next the adjuster handle was fitted over the peg and between the two locating lugs on the fixed runner. Then the other runner was put in to place and fixed to the seat. I have head restraints fixed to the seats, so it was okay to fit the adjuster bar at this stage. If you have head restraints fixed to the roll over hoops, then the adjuster bars should not be fitted for the IVA test as the seats need to be in a fixed position.

Two runners and adjustment bar fitted

Now I just need to fit them to the car

Seats and leather trim arrived

The seats, headrests, door cards, gear lever gaitor, handbrake gaitor, dash padding and dash leather have arrived from Intatrim.

The seats and leather trim (less the dashboard)

They are Muirhead leather in black (DA099), with red stitching to match the carpets.

Red stitching detail can be seen above

Carpets - couldn't resist

I couldn't resist trying out the carpets. I laid out the transmission tunnel and the outer sides, then added the rear bulkhead and floor. My excuse was to get rid of any creases! I think it should look brilliant against the white of the car..

So here is a quick pre-view! I am still undecided whether to have a black leather tunnel cover and rear section, but plenty of time to decide.

Carpets loose laid

Black leather seats, door cards and dash should set it all off nicely.