Airbox

We spent a while looking at options and designs of airbox. The main requirement was to fit under the bonnet without too much metal work so that we could mount the filter internally. This should mean a reasonably quite induction noise which will be essential to pass the noise emmissions test. We have been a bit worried about this element as I used to have a modified Peugeot 205 GTI which ran throttle bodies and sounded a bit like a canal barge trying to achieve earth orbit, even at idle. Fortunately A T Power (who supplied the throttle bodies) had a link to a company called Reverie, which makes among other things carbon airboxes in a multitude of designs. After much measuring up and head scratching we settled on a model that fits the bill, the Zolder 65 with shallow baseplate option.
The next problem was mounting it - carbon fiber is not easy to cut, makes tonnes of very nasty dust and obviously is not cheap to replace if you get happy with the power tools. So we cut a template out of mdf wood to match the intakes and clamped it to the backplate. It was then straightforward to use a hole saw to make the apertures in the correct place and all was calm in the garage. It looks, although we are proud parents, bloody good....! We had to file down the quick release tabs so that they didn't stick up too far and then it was on to the next task - cutting the hole in the already painted bonnet. Eek!

Vacuum purge supply

In order to have a vacuum supply to purge the carbon canister we had a piece of fuel rail section about 10 cm long drilled and tapped along the top to accept four hose adapters. The A T Power throttle bodies are supplied with blank ending bosses which can be drilled through to the chamber for just this purpose. The hoses were then connected up and this new balance chamber suspended from an engine bay cross member beneath the inlet trumpets. Finally, the ends of the rail section were plugged and tapped to fit a takeoff for the adjacently mounted MAP sensor at one end, with the other leading to the solenoid valve scavenged from the original Focus engine. I managed to modifiy (saw up!) the original bracket which has a nice fitted rubber collar for the valve, and by bolting this to extrusions which used to hold the water block at the rear of the engine we've been left with a very neat install. By my standards anyway......

As a note, when the engine tuning started, Paul noticed a pressure oscilation in the balance chamber which was throwing off the sensor reading. We presume this is either resonance or due to a steal between a pair of TB chambers. Either way we were unable to eliminate it so in the end the MAP sensor was isolated from the vacuum balance chamber and now supplies atmospheric info. Paul was able to work around this in the tuning process and it hasn't affected us at all - as witnessed by the IM 240 pass recently. We may try a different design of chamber later on but, as the saying goes, if it ain't broke have a beer instead

IM240, the emissions.......

Well, we can hold back no longer. The car went to VIPAC a couple of weeks back and..........passed the IM 240 with flying colours! To say we are happy is an understatement. We can only thank Paul Flourentzou and the guys from Chasers Motorworks once again - it was Paul's tuning skills and their help that got us through first time. In fact we got in well under the required emissions levels, so they really pulled it off.
It's not an easy route to take but hopefully this shows what's possible with an aftermarket ECU and throttle bodies.

Rear Lights

We bought these lights from the Caterham shop as we felt they are closest to the look we are after. It's easy to make the rear of these cars look like a trailer (and I'm not totally convinced we haven't achieved that!) but whilst the round single units look more traditional they can also start to look a bit cluttered. You pay your money and take your choice.
That being said, because we're having the spare wheel on board, the requirement for two reversing lights to keep visibillity up to happy engineer levels will look a bit overdone anyway. Ho hum, you can't have everything.

The process of fitting requires some masking tape, a spirit level and repeated check measurements from reference points. It's one of those tricky jobs and the complex curve of the rear guards means that when you finally tighten the retaining bolts, the rubber mounts of the lights can distort and change what you thought was a perfect level to ever-so-slightly off. So we will leave them to settle and adjust them gradually over time. It's exactly like trying to hang a picture on a wall thats not quite square....you're never totally satisfied!

Centre Console

We put this one off for a while as the molding didn't really sit squarely on the transmission tunnel leaving a few gaps. After a little shaping around the edges with a trusty file we got it to sit flush and central , so then we addressed the problem of mounting it. The manual (and I can hear other Birkin owners laughing at the mention of this word!) suggests riveting it in, but this means it is a harder job to dismount if you need access to heater controls etc so we looked at other options.
Our solution was to position it and then place two strips of tape on its side, overlapping the edge with the transmission tunnel. We then cut the tape, removed the console and riveted two angles of aluminium sheet to the struts in the tunnel adjacent to the tape left behind. Next we drilled a hole through the tape marked console and offered it back up to the transmission tunnel. This allowed us to mark the bracket for a corresponding hole to be drilled. Finally, we used a speed nut slipped over the brackets to provide a threaded surface and voila - a removable centre console with the added side support of brackets.
It took less time to do than to describe, but we are insanely proud!!
The panel has controls for the heater, washer wiper, a 12volt power supply (in case we ever break down and mobiles are flat) and the LED for the immobiliser. It looks very smart and we are experiencing the sin of pride once more.

New Loom

As a result of our decision to run with throttle bodies midway through the build, we have removed the original loom and had a new custom loom created. This sounds mad, but we would have had to modify so much of the engine loom that it would be virtually new anyway. Fortuntely we were able to sell on the loom via the grapevine to another Birkin builder so we haven't lost out too badly.

Our new loom was designed, made up and fitted by G.R. Motorsport Electronics and should, quite frankly, be in an art gallery. Like all genuine motorsport devotees, the chaps there really know their stuff, and were incredibly good to us throughout the whole process. Despite the fact that we must be pretty small fish to them they made us feel like we were developing a Le Mans special! We went with a Motec M400 on the recommendation of our tuner (more anon) as it had the power and flexibility to give us the best chance of pasing emissions testing requirements. He is also an expert with the software, which helps!

Confession time - Throttle bodies!

We have planned from the start to attempt to pass emissions testing on throttle bodies rather than the standard Ford manifold and ECU. This was and is a less than easy approach. Everyone spoken to has warned of the difficulty. The fantastic thing about the clubbie community is that there is always help and people have been incredibly generous and frank - the last thing you need is to start something like this in the dark. However we are nothing if not stubborn! We suspected the emission requirements might relax a bit and this now being the case we feel we are in with a chance. In order to avoid large egg/face interface scenarios when it fails dismally we have obviously kept a bit quiet but now that we have confessed we'll keep the blog updated more regularly. We still have all the OEM manifold gear so if it does fail we will just bung that on again and mark it up to experience.

Anyone who may have read earlier post might have noticed the bodies in shot already - they are from a company called AT Power in the UK. They have been designed for the Duratec motor as direct to head replacements and they are magnificent. The quality if the engineering is outstanding and I have seen video of them running on a clubbie - the induction sound is outrageous. Yippee!!!

Carbon Canister and Fuel Reg 2

Not earth shattering but I remade the bracket for the carbon canister from aluminium strip - it won't rust and I can almost hear Mr. Chapman's approval. Or maybe it's Gordan Murray....one of the two. I also added a moisture/dust trap to the manifold pressure outlet on the fuel reg - this isn't used in my car as it's non turbo - by coiling some hose and lock tie-ing it on.

Heater Fan

We attached the fan to its mounting point by drilling 2 holes in each side and making a small aluminium plate to act as purchase for the rivets. It was then riveted in place and the mounting bolts for the brake and clutch resevoir holder used to clamp the mounting plate firmly to the scuttle. This means that it is firmly attached despite being quite a heavy item and hopefully shuold keep supplying warm air for the Victorian winters in years to come!

Rear Caliper Issue

On bleeding the rear calipers we discovered an issue - they leaked badly. After attempting to tighten them with force failed, we loooked a bit more closely and discovered the bleed valves were placed inside two adapters. This looked odd so we removed them to discover the adapters were BSP or NPT fittings that had beeen forced into a straight walled metric fittings. Any seal formed had been acheived by mangling the first few threads and bunging on some sealant.

I would strongly urge those with birkins of this era to check up on the calipers as it is not a great engineering solution. After peering under cars with similar calipers it would appear that Birkin have swapped the position of the bleed valve and brake line - leaving a fitting too big for even a truck bleed valve and hence the "solution!" We had the original hole retapped and coiled and ground off the lip in the casing to allow the brake banjo fitting to leave the caliper at the right angle. This meant getting a larger banjo fitting attached to our brake lines and getting bleed valves that matched the original smaller holes but the end result is a system that has not leaked a drop and has the bleed valve at the highest point of the caliper where it was intened to be.

Battery Mount

There's a few places to put the battery, including on the scuttle or in the nose by the steering rack. The former is low but out front, and also awkward to reach for those jump-starting moments which I'm informed are pretty regular occurences. The scuttle is good but we're trying to keep it uncluttered - especially as we're planning to put a huge air filter there some day. So we decided on the wall in front of the passenger footwell.

First we riveted in a plate to the chassis tubes to help take its weight, and covered this in foam strips from Clarkes. We then got a steel bracket made up to enclose the battery and bolted this to the footwell wall. Rob from Meridian fabricated the bracket as it's something they've made several times before and it fitted nicely. We had to take a bit off the edge of the starter  motor and cut a resess in the bracket to allow for a bell housing bolt - we expect the engine to rock a bit under torque and don't want them to touch. All in all the hardest part was drilling in  a confined space and a right angled drill bit was a big help for this. We still managed to scuff the bracket but rest assured this will be tidied up soon!

Water Rail

We have finally added the water rail which is from Raceline. It's a lovely bit of engineering, with plenty of take-offs for temp senders and heaters. Due to the Birkin headers being a bit tall, it does need some modification to fit over the exhaust manifold of number one cylinder.

This was achieved with the angle grinder and a metal file. Rob from Meridian welded a plate over the resulting gap and once a few troublesome bosses were ground off the engine block the rail fitted as nature intended. It looks great!

Carbon canister and fuel reg

 We've used a Toyota MR2 carbon canister as it's very small and fits nicely in between the tank and the side wall of the chassis. The bracket was fashioned from 2 hose clips riveted to a strip of steel which had been bent to suit the profile of the canister. The canister was wrapped in two strips of sticky foam, the clips tightened and the whole thing was bolted to the car with minimal stress. Which was a first......

At the same time we attached a fuel filter and pressure regulator to the back wall of the cockpit, as our pump doesn't have one inbuilt. They are pretty standard items and again didn't require any Anglo-Saxon language. We'll tidy up the lines as we go along as I think they will need protecting from abrassive contacts - for now though we'll just cable tie them out of the way