Building our AC Cobra 289 LeMan

Mark had bought a new polishing set from the internet and decided to put it to work by polishing up the newly wielded throttle linkage bracket and header tank. They look amazing and now ready to fit. Hopefully we’ll get another weekend soon to get the build moving forward again. Watch this space.

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Once we had done the final fit of the throttle linkage, we looked at it once again and thought to ourselves that there might be a problem with the lower bracket once the engine was running . As its only fixed to the inlet manifold at one end, we thought this may allow it to flex (a bit like a diving board) and over time may cause it to snap. So Mark set about once again to make a few improvements. His solution was simply to make a new piece of bracket that could be wielded onto the existing bracket, allowing the other end to be bolted to the the back of the engine head, making the whole unit even more solid.

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We both arrange to get another day together to get on with the build. The last weekend we both had free was end of February where we had respraying the footwells. We were keen to get cracking again. The first job of the day was to refit all the bits we striped off in order to do the painting. This included putting back the peddle box, battery shelf and brake reservoir bracket and reconnect the throttle linkage.

Mark had spent a few more hours over previous weeks polishing up the rods and blades getting them extra shiny in preparation for the final fit. We decided as a little extra that we would make some extra plastic washers for the rose joints to try to prevent any potential rattles between the joint and the bracket.




Once altogether and everything fully tightened up, we then spent over an hour tinkering to getting the leverage of the peddle between idle and full throttle absolutely perfect. I’m glad to say we finally got there. Considering Mark designed our mechanism (based on photos of Andy Gordan’s Car) we are really happy and think it look great.

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We decided we’d like to repaint the white on the footwells as while we were fitting the throttle linkage and accelerator pedal we had managed to scratch it in a few places. So we striped everything down including battery tray, reservoir bracket, throttle linkage, accelerator peddle housing and peddle box, before masking the whole area and respraying. We can then reassemble it all over again.

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The final job for today was to fit the radiator into the front on the engine bay. This proved to be a fiddly job due to its position and we jacked up the front end to get better access. We got the radiator kit from Gerry, which has a large capacity and made from copper which should give better cooling quality. It came with 2 angled brackets to bolt into either side of the body.

Firstly we posted the radiator in from underneath to work out the position for the brackets. Its a very snug fit which is good but meant we had to carefully manoeuvre the radiator in and out a few times while drilling and fitting, careful not to damage the fins in the process. We haven’t got the fans yet but we’ll measure up for them soon and get them fitted.



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We decided at this point to get the throttle linkage mechanism finished and fully fitted. We did the first fit back on 28th January, but now we have all the necessary bits to finish off.

This involved connecting the springs to the throttle lever on the carb and Mark’s newly made bracket as well as make all the connections tight and fully lined up. We carefully worked out the leverage of the throttle going from idle to full to make sure there was always some tension in the springs at all times. We then marked up the position for the spring holes before drilling and connecting them up.

Next we added smaller springs either side of the connections on the transverse rod. This is to keep everything inline as well as to allow some movement when the engine is running. We secured these all in place with collars either side.

When we originally fitted the throttle linkage on the 28th Jan we made a temporary bracket to secure the transverse rod connection to the inlet manifold. The intension was to design and make a better solution and since then that is what we have done. We marked up 2 pieces of the stainless steel for the new bracket and asked our uncle Dave if he could wield it together for us along with a threaded boss on the top that the rose joint screws directly into.

To finish the 2 brackets off we rounded off the corners then shortened where necessary before polishing them both up.

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The next 2 little jobs were to fit the battery tray to the nearside and the reservoir bracket on the offside of the engine bay. Gerry had made up the battery tray and it arrived last week. These were quick and easy to fit, marking up the 4 bolt holes either side, drill through using a 90 degree chuck and secure with nuts and bolts provided. We will fit the battery and connect up the master cylinder later.

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We planned to get some more time on the car this weekend. We have planned to get most of the little job under the bonnet out of the way today. First job was to fit the new braided fuel pipe that Mark got made a few weeks ago to replace the rubber one we originally had. We fitted the connecter to the fuel regulator and ran the pipe through to connect to the carb. Mark had made a new bracket that bolts to the top of the inlet manifold which will eventually serve as the attachment for the springs onto the throttle linkage, but is also perfect to attach a stainless steel P clip to hold the fuel pipe in the correct position and to prevent it rubbing on the plug leads.

The last job will be to polish up the bracket nice and shiny, which we’ll do later on. Onto the next job…


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Once the throttle peddle and pivot where fitted, we moved onto fitting the throttle linkage to the carburettor. This is something we have been thinking about for a few weeks. We had the option to get the bits from Gerry but Mark wanted to design and make our own system. We had pictures of Andy Gordon’s Cobra at Silverstone, once again we used his car as the inspiration as we thought the solution he found was quite a neat one.

Mark spoke to his engineering department at work, asking them if they could manufacture the blades for the rod linkage and also some stainless steel strips, cut to size, that we plan to make a bracket from and mount to the inlet manifold. We have made a temporary bracket for now, that we will replace with a better one later. We have marked up for the new bracket that we hope to get our uncle Dave to wield for us.

We fitted the rose joint on the top of the footwell first. we then slid the 10mm rod into it. We then put another rose joint on the other end which we lined up and marked the hole to be drilled on our temporary bracket fitted to the manifold. Then drilled the hole and fitted the rose joint onto the bracket. We then fitted a blades to each end of the transverse rod.

We linked the blade to the carb using 2 female rose joints and 8mm rod. we had to tap a thread to both ends. We connected the other end to the peddle in exactly the same way using a shorter 8mm rod.
It took a little time adjusting the lengths of the rods to get the travel of the pedal correct but it works really well. We have just got the final bracket to make and fit now to finish this off.

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We started today thinking it was about time we fitted the peddle box. As we had already cut the hole in the footwell ages ago, its a job we could now do as the body is back on. The bolts go through the floor and flat section of the chassis and it was just a case of lining it up, marking up and then drilling the holes through. As the end of these bolts are exposed under the car, Mark had bought some stainless steel M8 bolts for this job, so they won’t corrode when exposed to the weather. Due to its position it proved a bit awkward getting these in and getting them tight. Mark bumped his head on several occasions while he had his head stuck down the footwell trying to get the bolts in (Hopefully knocked some sense in). We had noticed before hand that the floor of the body wasn’t quite square so we had to use a small piece of fibreglass, that we saved from cutting the original hole, to pack the front edge, getting a good seal between the vertical edge and engine bay.

Next up was to negotiate the position of the throttle peddle. The throttle pedal is posted through a hole in the top of the peddle box with the throttle pedal housing mounted on top inside the engine bay. We read through the Hawk manual and it didn’t really give any hard and fast rules for the position, although when we had spoken to Gerry at the NEC he told us to aim to mount it about an inch from the front of the peddle box. So this is what we aimed for. We initially drilled a small hole posted the peddle through to get a rough position. We wanted the accelerator peddle slightly further forward than brake and clutch peddles but for all 3 peddle to be equally spaced apart. From there we marked up the holes, drilled and fitted. This was also a bit fiddly due to it being under the wing and had to use a 90degree drill bit for this job.

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