Saturday 16 March 2013

Car Limits Day at North Weald

Yesterday I went to the Car Limits day at North Weald airfield.  There were a few of us from the Southern Kit Car Club, with 25 cars in total attending the day.  These ranged from a Ferrari 360 to a Ford Escort Estate!

The weather wasn't very kind on the way there and back, but wet tarmac made the session that bit more interesting.  I learnt a lot about handling car, which could never have done on the public highways.

Here is a short video of a couple of the circuits:


Thursday 14 March 2013

Mud Flaps

Often when out on a run down country lanes I find that I end up having to drive the car through puddles or being caught in a heavy rain shower.  With the positioning of the front cycle wings there is quite a bit of space for the water to spray up towards the side of the car, the occupants and even the interior of the car.  It was time to do something about it.

I bought 3mm thickness rally car mud flap material.  There was 4mm available, but I thought that would be too heavy.  Fortunately one piece of material cut in two was the perfect size for each side of the car.  A couple of 4.8mm rivets were used on each mud flap to hold them in place.  I positioned the mud flaps about 65mm above the ground so as to prevent them being caught under the wheel when reversing up a bump.  This could tear the cycle wing off the car.

I've been out for a test drive, up to motorway speed.  The mud flaps seem quite stable and didn't fly off!  I now just need to find out if they actually stop the spray of water from the road.


Wednesday 13 March 2013

Raceline Wet Sump

I have never been entirely happy with my sump installation.  In particular, the fact that there is no baffling, with the consequent risk of oil surge when driving hard.  When building the car I had changed the standard Zetec oil pressure switch for a lower (15psi) version.  This at least should give some advance warning of oil pressure problems, but by the time it illuminates permanent damage to the engine may already have occurred.

In 2012 I did have one trip to Brands Hatch and one to Curborough Sprint Circuit.  While I had no oil pressure issues on these two occasions I started to think that I'd be pushing my luck with the three track sessions that I have booked this Spring.

So I decided to bite the bullet and upgrade to the Raceline wet sump.  This is very highly rated by those that use it.  It is even used on many race cars.  Most racers considering it to be good enough that at upgrade to a full dry sump installation is not even necessary.

The old sump was removed without any major problems.  Then it was time to start preparing the Raceline sump ready for installation.

Here is the main pan.  It is a very nice piece of engineering and you can see where the effort has been spent on the design, the casting and the machining.


Here is the Ford windage tray, Raceline windage tray and oil pick up pipe, etc.


First the oil pick up pipe is installed, with two rubber o-rings to make a seal into the main pan.  A metal filter gauze is inserted into this pipe from the outside of the sump.  This can be removed and cleaned at oil changes, if required.


Next the Raceline windage tray is bolted into place.  This windage tray is one of the methods used to control oil surge.


After that the Ford windage tray is bolted to the Raceline windage tray.  The Ford windage tray is designed to 'scrape' oil of the crank and con-rods.  Helping the oil to fall to the bottom of the sump and not be whipped up into the main engine block.


Standard Zetec Silvertop sump gasket fitted along with oil drain plug and gauze filter plug.  There is a double top hat spacer with rubber o-rings fitted that makes the oil seal between the sump pan and the engine oil pump.


The sump itself fits very well.  The main issue, and one which consumed a lot of time, was getting access to all the sump bolts.  Many are hidden by things like the starter motor, engine mounts, etc.


The old Tiger ERA sump was higher than the gearbox bellhousing.  The Raceline sump is level with the bellhousing.  The previous sump had around 100mm of ground clearance, but unfortutately the Raceline sump only has about 65mm.  This is too little, especially as the car is used a lot on country lanes, where there is often a raised centre to the road.  So the springs on the front dampers were wound up by 20mm.  Due to the geometry of the wishbones this translates to an increase in ride height of about 35mm, i.e. back to around  100mm under the sump.  Result.  I will take a look at the rear ride height as soon as I can and get the car leveled again.

Before running the engine for the first time I removed the plugs and rotated the engine by hand (socket set on crankshaft pulley).  I wanted to make sure that the Ford windage tray was not fouling the crankshaft or con-rods.  Next, I took the spark plugs out and cranked over the engine until the oil pressure light went out.  Once this was done it was time to fire up the engine and go for a test drive.  I'm happy to report that so far all appears to be working fine and there are no leaks.  Roll on the good weather and some track time!

Sunday 10 March 2013

Cooling System Updated (Again!)

  1. As advised by Tiger I originally ran the car with no thermostat and no bypass plumbing.  I understand this is a fairly standard set up for race cars.  However, if quickly became apparent that the engine was being over cooled.
  2. My next configuration had a thermostat with a 3mm hole in it as a bypass.  This worked very well all summer - the engine stayed at a constant 88oC, unless the fan needed to cut in.
  3. Once the cold mornings of autumn arrived the engine started to run cool again.  Things were fine at lower speeds, but once there was a significant air flow through the radiator the coolant temperature struggled to maintain 80+ oC.  So I decided to introduce a full bypass pipe and fit a thermostat with no bypass hole.  To do this I had to fit a thermostat housing from an earlier Silvertop Zetec.  This was necessary in order to fit the coolant temperature sensor in a place where it would get a reading prior to the thermostat opening (as the Blacktop Zetec housing has no sensor holes and I'd previously had the coolant sensor in the main pipe to the radiator).  This set up generally worked very well, but there was one problem: somehow air from the expansion tank would make its way to the top of the radiator, which is higher than the pipe that feeds it from the thermostat housing.  A little bit of air would get trapped there each time the engine was run until there was sufficient air there for the flow of coolant to break down - not good.
  4. So one more modification and hopefully the final configuration.  A 8mm hose barb was welded on to the top of the radiator and plumbed into the pipe joining the thermostat housing to the expansion tank. Now all works well.  Any air can return to the top of the system and an added bonus is that the hole coolant system is now self bleeding, which will help when I come to renew the coolant at future services.
Here is a schematic of my final cooling configuration:


8mm hose barb welded in to the top of the radiator.  It is just above parallel with the ground.  This is to allow it and the pipe to fit under the curvature of the nosecone.


Full routing of the new pipework (apologies for the poor quality mobile phone pictures, must use the proper camera next time).


C-shaped brackets were fabricated from aluminium strip.  These were fixed under the camshaft cover bolts and rubber lined p-clips were riveted to them.