Conference terri::cars_uk

1443.0. "Sprite MkIV 1600TC Conversion" by ESSB::DOODY () Wed May 15 1991 11:33

In reply to a previous note re MG Midget restoration I mentioned that I too am
restoring an 1967 Austin Healey Sprite Mk IV. However I am 'uprating' 
(and I wont argue over originality issues) it to Fiat 1600TC + 5speed gearbox
spec. Here as promised is a description of what was/will be involved.
A lot of stuff is hard to describe and would really need to be seen.

The car is presently at the engine running to full warm-up temperature
/drive 5 yards stage.

OBJECTIVE: Build reliable quick Sprite which looks original and which
           has no bumps/mods to the bonnet or exterior bodywork

Engine/Gearbox transplant:

A) Remove heater unit + front 4" of battery tray under it
   Relocate battery to boot.
   Heater unit now lies flat in this space and brings air in through
   ford escort fan lying nearly horizontal through Fiat 132 heater element.
   ducts inside car all moved up by 3" approx. Original ducting has been 
   extended slightly Inlet/outlets are now at each side of engine bay to match
   engine. 

B) Steering column had to be cut, and using two UJ's + connecting bar + tube
   + bushings from a Fiat 127, was raised to lie to the passenger side of the
   present accellerator cable mounting over the drivers left foot. In order
   for this to work the steering rack had to be rotated ~10 degrees.
   The position of the steering column/Wheel is unchanged except for the 
   addition of a second steering column bracket 6" down from the original.
   The top UJ is located inside the drivers compartment above the drivers knees.
 
   This was not as difficult as it sounds and has the added advantage of
   removing what was for me the most serious prospect of the steering column
   in the original spridget impaling the driver in the case of a front end
   shunt. Maybe to be recommended in all older spridgets regardless.

C) The original engine mountings were unbolted, and new ones fabricated which
   which are located each side of the longtitudinal chassis rails. (A friend of
   mine did this for me, and very neatly too). Minor bodywork mods also needed.
   Then Engine installed and very simply too.
   
D) The floor of the gearbox tunnel had to be cut back approx. 9" removing the
   original gearbox mounting area. The floor was then strengthened from sill to
   sill across this line. An integral stiffener bolts in under the fiat gearbox
   The Fiat gearbox mounting bar + gearbox mounts, bolts through the floor onto
   the strengthened area. The tunnel had to be heated and locally dished in
   certain areas for clearance. But was essentially simple to fit.
   The gearstick locates almost exactly the same as the spridget 
   and uses the same rubber boot, I had to stretch the metal cover bowl inside
   the car to clear the top of the box.

E) Propshaft is spridget with Fiat sliding joint + rubber bush.
   Retains the 2 original spridget UJ's - This has yet to be balanced.
   It lies in almost the same position as the original.
   
F) Clutch: This is where my problems started.
   The Fiat clutch release bar sticks out of the side of the bellhousing
   and fouls on the spridget chassis rails

   I experimented with all types of mechanical/fluid clutches
   + combinations of these but each time failed due to the
   extraordinary amount of effort needed to press the clutch pedal.
   
   I have somewhat solved the problem by using the cable setup from the
   Fiat pulling directly the release lever which has been bent/supported
   90degrees from original. It is still quite heavy but
   usable. (Anyone got any ideas for servo-assisted clutch???)
   I'm using the original spridget clutch pedal.

   The main reason for the problems is that the pedal travel is
   about 2/3 that of the original fiat setup and i didnt want to change the
   pedals inside the car. 

G) Cooling: uses spridget radiator with front mounted fiat cooling fan
   radiator modified at base by insertion of fiat temperature sensor.
   Problem: Radiator is lower than highest part of engine cooling system.
   Solution: fit bleed valve into to rad hose. Fitted Ford Orion header
   tank to bulkhead at passenger side (the slope is almost exact match).
   This took a lot of figuring out, but engine now will run for hours at
   tickover and won't overheat.

H) Oil filter: Have bought a remote oil filter from Merlin(Castle Coombe)
   but havent fitted it yet. A Renault 5 Oil filter fits (2" high) but
   there is only about 5mm clearance and I cant raise the engine because
   it would require a 'power bulge' in the bonnet which I dont want.
   Usual mods to oil pressure supply/oil light.

I) Exhaust: The same friend did this for me. the fiat 4->2->1
   header setup has been retained and the original pipe lengths.
   however i am stuck with a 'bunch of snakes' which requires me to
   lift the engine 6" in order to remove the headers. rear portion
   is spridget 1500. This setup works well but is unwieldy in practice.
   There are a lot of welds and really can be at best a template for a
   proper setup.
   (I eventually will get this professionally made up)

J) Carburettor: Low 1" pancake filter is used.
                Accellerator is spridget + fiat cable.

K) Electrics: Retained spridget dynamo, polarity changed to -earth, tach 
   changed as described in Lindsay Porters book: 'Sprite & Midget restoration'
   (great book). Starter is a pain : Engine must come out to remove it 
   [I am thinking about some sort of removable panel in the passenger footwell].
   I split the main loom just inside the dash and fitted block connectors 
   to allow easy dash removal in the future. 

I am leaving rear diff ratio/uprating the brakes/suspension until the car
is back on the road.

All of this has taken about 2 years of mainly weekend work. Things are at a
standstill at the moment as I have just moved into a new house and am 
completing a workshop. I have purchased all the replacement
body panels i need and hope to buy a MIG soon and get back to work on the
sprite ASAP.        

Sacrilege maybe! but it promises to be one hell of a car to drive.

Brian.
    

    Well done! A persistant man indeed!
    
    I'd like to see this thing when it's finished. Where are you located?
    I'm in Brussels at the moment, but I will probably be in the Reading
    area with the Frogeye around the end of July.
    
    Laurie.

If your ever over here, no problem. The car is presently in a garage at my
parents house in county Laois - I aim to have my workshop completed and the car
in Galway around the end of June/start July.

Brian.