A Dream Fulfilled - MY 904FF

[Kirklands 904]

When the car was up on the rotator, the opportunity was taken to revise the "bum" tray which gave a lower seating position which meant that I could sit without my crash hat touching the roof.





To accommodate the 6 cyl engine, the engine mounting locations needed to be moved forward. The actual mounts are competiion ones which are a bit stiffer than standard and were used on the 4 cyl engine. The same mounts are used on the back of the gearbox.




Mike recommended that an engine mounting cradle be made to spread the load but also to give better access to the front of the engine rather than a standard mounting bar.




At this time, thought was being given to an exhaust system and having good experiences previously with MittelMotor in Germany, we decided to look at their 914/6 competition exhausts. Andy did not believe he could fabricate one any cheaper and advised that I buy the Mittelmotor unit and he could adapt it as necessary.





We decided that when actually seen on the engine, it was the proverbable canine's appendages.

[Kirklands 904]

When competing in the 4 Cyl, I had ran into some problems with certain scrutineers who were not exactly thrilled by the battery being in the front under the fuel tank! It had been placed there to try and even up the weights front to rear and compensate for the lump in the back. I decided to buy a Varley red top and housing and it would be fitted on the opposite side to the dry sump oil tank.




On the other side, a mounting bracket for the oil tank was fabricated and fitted by Andy.



Now we get to the difficult bit, the actual oil tank. The decision was made that it should be made and fitted to the right hand side of the car. It was to be LARGE and incorporate a swirl tube on the top as the oil returmed to the tank from the oil radiator at the front.





Talking to Mike Bainbridge at regular intervals, he expressed the view that the oil tank should be on the other side so Andy set to and made a left handed tank to fit where Mike advised.







So we now had an oil tank but what of the rest of the oil system.

When the real engine had been collected from Cumbria and fitted into the chassis, we were now in another "Oh shite" moment. The oil cooler on the engine was now in the same space as part of the chassis. In other words engine was installed but no oil cooler. Luckily in Malton there was a Porsche specialist Sam Lander who had been asked to pop in and answer any Porsche type questions. When he saw the problem he immediately said that a 993 housing and filter would fit rather than an oil cooler. In other words the oil would go through a filter rather than a cooler.



It was all very tight round the engine and the gearbox oil pump drive had to be removed and was returned to Mike as for hill climbing and sprints there was no need to have a gearbox oil cooler. We had decided that there should be a filter to protect the front oil cooler and this was installed close to the oil tank.




We were making progress with the oil system now which now had two filters and capacity in the tank of approx 15 litres. We run with 12 litres and the oil temperature hardly registers on the gauge.

I have always believed in the principle that oil is cheap compared to a blown engine but the oil and filter change each winter does bring a tear to the eye.

[Gary71]

Some lovely engineering going on here.
Keep posting!

[911hillclimber]

Hello Bill, fully understand what all this has been to you and the Team!
What are the rear uprights off, Westfield?
JUST GONE BACK IN THE THREAD BILL, DOUGLAS UNITS.

Hope you have entered some of the same events as I have so I can see the car again.
Graham.

[bjmullan]

Fantastic build Bill, and glad that you got posting pictures sorted!

[Kirklands 904]

Graham, At the present time, I have entered for all the Shelsleys and Blyton in May. We shall see how the year develops and it will depend on how the car is going and how I stand up as to whether I enter any more. I shall not be going north this year as Bo'ness is not taking place.

[Kirklands 904]

I think that I had mentioned previously that Mike Bainbridge had built a transmission with two first gears, one in its usual dog leg position and one where second is normally to be found. This meant a conventional "H" pattern for competition and the other first opposite reverse for maneouvering in the paddock. George then set to to make a proper gear shift linkage to supercede the cable shift that Pete Bentley and I had made for the original tail shift box and which was not that reliable.

The transmission from Mike Bainbridge had the shift lever into the sideshift box as shown.



George then modified this to have a support for the rod at both sides of the gearbox shift lever which can be seen on this pic.

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The rest of the linkage back to the shift lever then had to be slotted into the space not taken up by the exhaust and chassis tubes.



A lockout device was fitted to the gear lever which meant that the the rod attached to the gear lever had to be pulled up to select reverse and a first. In other words to protect "the paddock plane" from ham fisted operatives in the driver's seat.

Up to the time of speaking it has proved bullet proof. What a relief to know that all the gears could be found without fumbling!

To finish off this gear change sector, the clutch pull cylinder used on the four cylinder engine was adapted for the six.

[Kirklands 904]

As well as the gear change linkage, George had also revamped the steering column area and fitted a detachable steering wheel. Not only did this look neater but saved a good few kilos compared to the original from the donor 914. There was a general concern that, as I got more geriatric, it would be more and more difficult for me to get out of the car. It's always easier to fall into the seat with the help of gravity rather than to extricate oneself. There has been many a smile by those in the paddock watching me get out!



In period steering wheel obtained from Karmann Konnection. The blue knob behind the shift lever is the adjustment for the brake balance bar.

Andy had also taken on the task of altering the rear engine cover to make it easier to open and close. The arrangement I had previously was a pain in the proverbial since it meant scrabbling under the rear of the car to remove a couple of "C" clips and then two of us lifting the tail off completely.



The framework is attached to the tail via 13 ply blocks fibreglassed in place.



Now the screws could be taken out of the engine cover at the front and the tail hinged back without difficulty. It had all been designed to such fine limits that the tail could be opened in the Shelsley sheds with less than an inch of clearance. Sometimes Lady Luck is with you!!

[rhd racer]

Brilliant!

Some fantastic problem solving and engineering going on here, thanks for sharing Bill. Great thread

[Kirklands 904]

As George and Andy continued with the work in Yorkshire, I was taxed with sourcing other parts which were required. In the original iteration, the drive shafts were modified 914 to get the correct length but also to use the Ford hubs etc at the wheel end which, of course had different splines. These were made by cutting off the 914 outboard splines and sleeving on to the ends of the Ford drive shafts and the whole lot welded together. They had worked with less than 120 BHP but it was thought that we would be dicing with danger with 200 BHP. One of the originals was taken to Brand Mechanical Engineering Ltd in Aston, Birmingham to machine new shafts in proper steel, EN24T rings a bell but I might be mistaken. Of course there was a link back to Shelsley Walsh in that the late Bob Dayson had been involved with the company.



On an earlier post, I had mentioned that a Clewett system was to be installed and was advised to be careful with the plug leads as a DDK member had had problems with them breaking down on his Clewett system. Clewett recommended Magnecor leads so the piggy bank was raided once again and a set was purchased and taken to Yorkshire when I was delegated to wire in the Clewett system. The manual that came with the sytem has 36 pages to cover all engine configurations from 1 cylinder through to 12 cylinders and rotaries. The six cylinder variants are even-fire, odd-fire and twin plug. It took a bit of figuring out.
The XDI control unit was fitted inside the cockpit on the back wall and a mounting plate for the three coils was fitted on the top of the engine behind the fan housing.



To try and keep it as authentic as possible, I decided to use the original 914 instruments so the tachometer was modified to 6 cylinder and a square wave signal by Speedy Cables. The face of the instrument was not changed so the red line area starts at 5,600 rpm. Very useful when the noise police in the paddock check on the decibels produced. It still reads to a max of 7,000 so is still practical.

One other thing to mention at this stage is that all the friction material is standard and not competition. So a standard cluch cover and drive plate are fitted and the brake linings are a nice soft standard spec. Brakes in a hillclimb or sprint never get hot!

[911hillclimber]

They are indeed En24T, a wonderfully versatile steel alloy. Bob Dayson would machine the shafts (24T is machinable from the mill) and then slowly heat treat them to give the toughness required.
Apparently he used to fall asleep I front of the tempering furnace most of the day while the process completed. A legend of a man.

Bit of info Bill, I use a stock 915 clutch in the Lola with no probs and big slicks.

[hot66]

Fab looking build Love the gearbox details

I have the Clewett twin plug on my 2.4S .... might have been me that had the problems with the clewitt leads , a couple failed at the spark plug connectors. I replaced them like for like with some new ones and have since been fine. They do recommend changing them every few years though ( which I haven't )

[Kirklands 904]

James, I am sure it was you who warned me way back.

Those of you following this saga may notice that some photos which I was using when trying to work out how to post from Flikr have disappeared. Bootsy removed them at my request since they were out of sequence and broke the flow of the story. Keep patient and they will reappear with an explanation!!

[Lightweight_911]

.

Just caught up with your updates Bill - as others have said, some great problem-solving/engineering which makes for fascinating reading.

Hopefully I'll get over to Shelsley later in the year to see it 'in action' ...

.

[Kirklands 904]

Andy had, by this time, cut, welded and rivetted aluminium panels in the front to seal off the front wheel arches. We had also procured wheel spacers and longer wheel studs for the front as the new wheels just fouled the calipers and needed to be moved outboard a tad. A new shroud piece had been made to seal off the back left hand barrel which was now exposed by the 993 housing and oil filter.

The oil lines and breather tubes were installed and the thermostatic bypass used on MK1 was dispensed with. The oil tubes were increased in bore size since we wanted to remove any restriction to the oil flow going forward to the oil cooler in the front. As I said before oil is good stuff!

We were now reaching the stage where the bullet had to be bitten. The Clewett was wired up as per the manual even to the extent of powering the system with a separate fused feed (more of which later.) As usual, we turned over the engine without the ignition circuit being live. There was oil pressure and lovely clean oil flowing into the dry sump tank.

It fired up immediately when the ignition was switched on. Three very happy chappies!

However, there were a few oil leaks which just meant tightening up in a few places. One major/minor was oil dripping from pin holes in the oil drain tubes.

I should point out at this stage the space round the 6 cyl engine is tight. To install it, the first task is to thread the transmission between the chassis tubes, then lay the exhausts in place, lower the engine and connect it to the transmission. Finally to bolt up the exhausts to the outlet ports. A complicated and slow procedure. I blame the chassis designer!! The oil drain tubes are now very difficult to access. The only way to stop the leaks was to use the coca cola tin and jubilee clips method with globs of sealant.

Next step was a trip along the road to Dave Boggs to tune the Webers on his rolling road



Well, Mike was correct, over 200 BHP on the dial! Dave Boggs has been tuning engines fo ever and recommended that the jets be such as to run a little rich for the first season as the engine bedded down. He also advised me not to increase the choke size as the small chokes would give better pick up even though increased power at the top end would result from larger chokes. Since the car would be doing hills and sprints in the main, torque was the requirement, hence the "E" cams and small chokes.

It will be interesting to hear what is the opinion of the forum followers.