Saturday, 26 January 2013

The foot brake final assembly

The foot brake final assembly


The Sylva J15 has two separate master cylinders and a balance bar. The shape of the bonnet is such that the location of brake reservoir needs to be behind the tank next to the bulkhead otherwise you cannot get sufficient head of fluid (in my opinion). In my case this was a real challenge as my custom tank leaves very little room for the smallest of reservoirs that I could find.

There is also the favourite issue with the balance bar, in that it needs to be wired and an appropriate warning label added.The threads on the balance bar are M11 x 1.25, as it turns out I have a tap and dye for that size so I made some special nuts out of hex bar with locking holes in each hex corner and a turned down bit to lock the bar (see images). I do not claim originality here but I am pleased with the result. It was another item I was not confident about solving elegantly.

I did expect trouble with the RD Euroqip flexible brake pipes, as I had some trouble with the one on the clutch line leaking due to a shard of the ss outer getting into the olive, but this time all eight connectors worked first time. The only leak I had was a poor silver solder job on the lines I made up for the reservoir.

I did have trouble getting the air out of the system, despite my wife's best efforts on the brake pedal. I used my Easybleed and got the air out. I hate using the Easybleed as I find it difficult to control the mess with all that fluid around.

All i need to do now is adjust the balance bar and wire the lock nuts. the images showing the locking wire are for demonstration purposes should the IVA man need convincing.





 



 References

Thursday, 10 January 2013

Fuel filler cap

Fuel filler cap


The tank in my J15 was custom designed by me to give more leg room in the passenger side of the car.  In addition to the custom design a large aircraft style filler was considered desirable to minimise any spillage during filling. At the time of originally writing this I was under the impression I needed a lead free valve for the purposes of the IVA. If you read the comments it became obvious that this fine fabrication was not needed. However I never completely disposed of it and poat IVA I found a use for it. See "Fuel system modifications" 13th Dec 2013.

References

 
Rally Design filler cap
 

Tuesday, 8 January 2013

Heater

Heater

It is essential in Scotland, even with an open topped car to have a heater keeping your legs warm. I have had some great winter journeys in my Westfield and I was so grateful it had a heater.

I found a heater that is just the business for the Sylva, at a reasonable cost too,   Deamon Tweeks.

All I have to do now is plumb it in, the air ducts will go down the sill void.


 

References 

Demon Tweeks:
http://www.demon-tweeks.co.uk/motorsport/cockpit-ventilation/demon-tweeks-lightweight-heater

Contents http://sylvabuild.blogspot.co.uk/2012/01/sylva-j15-is-kit-car-designed-by-jeremy.html

Sunday, 6 January 2013

Handbrake cable routing

Handbrake cable routing

The rear uprights on my Sylva J15 are a fabricated part by Jeremy making reuse of the Ford donor drive shafts. Apparently it takes either a VW Passat or Hydra OEM calliper from Rally Design. The main problem with this arrangement is getting an adequate routing where the handbrake cable neither fouls the AVO shocks or more importantly the boot for the outer CV joint. The completed assembly must give a relatively friction free performance for the VOSA/IVA man.

I have thought long and hard about this problem and I have come to the conclusion there is no perfect solution with that Passat calliper. I may have to resort to trying out a hydraulic handbrake calliper if I cannot find a solution soon.

I did measure the outer dimension of the handbrake cable which was 9.5mm (including plastic covering). I also discovered that B&Q supply a piece of 12mm alloy tubing with a 10mm inner hole diameter EAN 3232630508756. I also have a plumbers bending jig for 15 and 22mm pipe. Putting all this together my approach for IVA is to clad the last 400mm of handbrake cable in this alloy tubing and then bend the whole lot to the exact shape to avoid the aforementioned obstacles.

I have now done this and as said before it is far from being an ideal solution but will it be good enough to get me through the test? Your comments are welcome. I can think of various potential pitfalls, like lack of cable flexibility resulting in a fatigue failure of the mechanism. I have jumped up and down on the chassis and it appears to be a good solution.

P.S. I also discovered there is very little clearance between the hydraulic connection and the outer CV boot. See image 2.




References


Contents http://sylvabuild.blogspot.co.uk/2012/01/sylva-j15-is-kit-car-designed-by-jeremy.html

Wednesday, 2 January 2013

Front wheel hub spigot rings

Front wheel hub spigot rings

The front hubs as supplied in my kit are an alloy assembly originally intended for a Caterham (formerly a Triumph Spitfire upright). They do not have Ford 108PCD spigot rings despite the correct Ford 108 stud pattern. Now some readers at this point may not know what I am banging on about.

Here is a quote from AUTO Inparts.com

"What are Spigot Rings and why do I need them?
Spigot Rings (Centre Rings) are used to ensure that an alloy wheel is correctly centred on to the hub of the vehicle. If an alloy wheel is fitted without spigot rings it will probably cause the wheel to vibrate, make it almost impossible to balance, increase uneven tyre wear and in time will work the fixings loose. So, fitting wheels without spigot rings can be very dangerous."

The hubs do have a ring that is 2.6mm high and 58.5mm in diameter. The Ford 108PCD spigot ring is 63mm in diameter and approx 10mm high. I therefore decided to make an alloy adaptor made out of a concentric wheel spacer similar to a DemonTweeks part see reference below.

I managed to get a pair from ebay second hand 10mm thick. These spacers assume there is a spigot ring in place already on your wheel hub and you are placing the spacer on top of the existing ring maintaining concentricity. By turning off 5mm from the inside of the spacer I effectively made a 5mm spacer without the starting camphor provided. I then turned a ring out of 63mm bar that matched the 58mm ring on the inside and the 63mm hole in the wheel spacer. I now have concentric spigot rings on both front hubs. I also have 5mm x 2 extra wheel width at the front. It appears the studs have plenty capacity for the 5mm spacer.

Excessive attention to detail, I don't think so. What do you think?




References

AUTO Inparts.com:
http://www.autoinparts.com/Wheel_nuts,_bolts,_locks,_spacers_and_accessories-Spigot_rings_for_O.E_and_Aftermarket_Alloy_Wheels/c628_897/index.html
Concentric wheel spacer example:
http://www.demon-tweeks.co.uk/performance/wheel-spacers/demon-tweeks-hubcentric-wheel-spacer

Contents http://sylvabuild.blogspot.co.uk/2012/01/sylva-j15-is-kit-car-designed-by-jeremy.html


 
 
 
 



Tuesday, 1 January 2013

The drive shafts and rolling chassis test

The drive shafts and rolling chassis test

I decided to use a company called CPS Drivelink to modify my drive shafts. The chap called Paul Sowerby is very knowledgeable. He proposed to friction weld the shafts using compatible materials. I did consider getting them remade by a chap Jeremy recommended but I got cold feet and decided to use Drivelink one stop refurbishing service and the parts would be ready to go on the car once returned from them.

I found the process of preparing to send them away quite stressful, I was told by Paul to cut and shut them by tack welding after removing a bit in the middle of each shaft and then trying them on the car. Even if I got it wrong he said, as long as long as I told him the error from what I was sending him +/- mm.  I devised a method of measuring the amount (30mm and 40mm) to initially remove the middle sections (see image). I then made up two mild steel sleeves and tack welded the whole lot together again. After I tried them in the car I appended a note to indicate there was no error.

The modified shafts were done within a week including transport, the finished shafts are now in the car and you cannot tell where they have been welded. A test drive of the rolling chassis was now in order. Before doing that I had to connect the clutch hydraulics, another stressful episode as the flexible hose leaked of course. I also had the slave cylinder, flywheel and lightweight clutch assembly replaced earlier in the year so was not 100% confident the cluch actually worked.

Anyway the test drive was a great success despite the only brakes I had was the handbrake.

The engine appeared to run too hot but that was a red herring as the temperature gauge is totally inaccurate for some reason. I checked it with a Laser/IR external device and the temperature is fine 80deg and steady.

Many thanks to my friend Angus for helping with the clutch bleeding and video record.

References

Video http://youtu.be/gv1rk9z7mhQ

Contents http://sylvabuild.blogspot.co.uk/2012/01/sylva-j15-is-kit-car-designed-by-jeremy.html