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850 Fiat 850 Coupe Hill Climb/Sprint car

Introduction

This is my Fiat 850 coupe I bought new in 1970. I drove it for 4 years and did all the usual things like get married and had kids. Sold it when we needed more room for the kids. The car stayed local. About 23 years ago when I was towing home a car for my eldest son to rebuild there it was, parked on the side of the road with a for sale sign! Looked a bit sad with plenty of rust but I jumped at it and for $250 I had my old car back with a spare motor and gearbox, spare doors, glass etc.


A few months ago it was announced there will be a motor racing complex built within 20 kays of here! I had already been involved with a club doing hill climbing with a MX5 but now I had some serious motivation to do something with the Fiat. My Fiat was built in 1970 during a period of unrest at the factory and like all the cars built then had poor paint and rust proofing. I had a partial repaint during the warranty period. I decided that the car would not see road service again so I set about building a car for hill climbing using the original motor to ensure it will be Fiat car club friendly! The division I race my Mazda in is up to 1600cc and the Fiat will be doing the same. I have an AMR500 supercharger that will still allow me to race in the under 1600cc classes and my aim is to get the car down to minimum weight. 15 kilos is about 1 hp!
I have gone to a front alloy radiator, wishbone front end and I'm flop moulding epoxy 'glass bonnet, engine covers. Retaining the original windscreen and will have have the rest of the windows in plastic. Lightweight starter motor, Suzuki 750 brake calipers for the front. I have cut out some sheet metal that was not necessary. Weight I have added is the super charger and the half rollcage. The photo below is from a couple of weeks ago. Car is now off the rotisserie. I had to fabricate two new sills and the A pillars both needed some creative metal work and there were a lot of hours spent there!
I will stick up more pictures later.
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This is looking amazing!
How have you done all those fiberglass panels?
Just out of curiosity, you wouldn't happen to have dims on the gearbox tunnel on hand would you?

Also in the front end, i've noticed that the radiator is out in the open.
Are you planning on making a cowl for that to ensure air is funneled directly through the front of it?

We've got a little 850 in the garage still which was dads first car new in 1969.
Which started out white and was stripped back to bare metal in the 70's to fix some of the rusting issues and repainted Ferrari Dino Red.
Mum always joked that these came factory standard with rust,
which i'm sure isn't too far from the truth.
(It appears the front nose near the lights were a common area)

I'm currently waiting for a tig welder to arrive as i've got a few sections which will need to be repaired including the passenger door sill.
also planning on upgrading the brakes to a set of motorbike calipers.
but have also been trying to find more info on the drum to caliper conversion. Which i believe may need a 124 Master cylinder to run correctly.

Also would love to see more on the wishbone setup. Was that an online kit or something you've fabricated?

Can't wait to see more on this.
 
Akkronos,
The fibreglass panels are simply flop molded straight off the steel panels. Packing tape is laid onto the steel panels as a mold release. Because I used epoxy and fibreglass cloth the thickness was very thin and after a couple of lay ups I just peeled of the new panels and then laid up more layers. The only problem doing this is the rear panel with the reset lights ends up being too small and needs some fiddling about. Because the Fiats of this era have sloppy panel fit the slightly over sized panels are not noticeable.
The frame work for the radiator will have aluminium sheets fully enclosing the intake.
I'm sticking with rear drum brakes because they are lighter but there is plenty of info on converting to discs. I have Tokico front calipers and sticking with a new single line stock master cylinder.
The wishbone kit was made in NZ and is similar to the units available in Europe. If I was doing the job again I might have gone straight to a kitcar front end and Cortina uprights if I was aware of the amount of fabrication I ended up doing.
What dimensions are you actually after. The engine and gearbox is sitting on the ground under the car at the moment ready to go in.
 
Engine and gearbox now in place. Fabricated an alloy engine mount for the rear. Rear suspension is installed. The gas shock absorbers are about 120mm higher, They are new old stock Holden units. Using kevlar rope strops to prevent the rear trailing arms to tuck under.

 
The engine is running now. Noisy but sounds really good. Having a lot of trouble getting the air out of the cooling system and keep blowing off hoses. Will have to try a bleed valve at the front radiator.
 
Update of photos showing the cooling layout. 1" Aluminium pipes running through the car.

Radiator is mounted low down in the front, installed a bleed valve to top up water and bleed air.

Water enters the block through the SS pipe in the supercharger mounting bracket into the old water inlet.

Pump is mounted opposite.

The thermostat is removed and the bypass pipe removed.

Expansion/top up tank mounted where the old fuel filler was and a pipe will run around and up to the top bypass position. That blue bit is a temperature probe mounting I welded to the water outlet on the thermostat housing. To bleed the air out I will unscrew the sender while the electric pump is running.
 
Have the cooling problem sorted now I think. The Bosch pump I had was not man enough.New pump installed today as low down as possible and on it's side at about 45 degrees so air does not get trapped. Its probably lower than the bottom of the front mounted radiator. I simply followed the Davis Craig instructions to the letter. Ran the pump with out the engine and cleared a lot of air out the front vent and out the temperature probe near the thermostat housing. Ran the engine a couple of times and bled some more air out the front. Engine warmed up quickly and all the pipes and radiator were at the appropriate temperatures, I checked the system with a laser temperature probe and was very happy with the outcome. I have a fairly large electric fan I will be switching manually to control the temperature when stationary in the pits etc.
 
This is a video of the engine running. Not the first start but the first after curing the cooling problem I had. Solved by fitting a larger electric pump and a vent at the front mounted radiator. Engine is slightly retarded at the moment and the SU has to have the mixture set. In reality the sound is totally different than what is on the video. Can not hear the induction noise over the exhaust when standing behind the car. Yes there is some whine when the throttle is blipped! Will add some extra exhaust pipe across the back of the car to give a bit of back pressure. Muffler is a Hooker Aerochamber.
 
Front suspension ready for a wheel alignment. Bilstien clubman coil overs. NZ made lower wishbones. Stock brake disc thinned down to 6.5mm and Tokico calipers. Little metal ground off the calipers and the bleeders will have to be shortened to fit alloy 13 inch Cheviot wheels. John Edwards caliper adapters.

 
Have not posted here for awhile so here is a bit of an update.
Have had no joy trying to get the suck through charger SU carby set up to run properly. Have now bought a Microsquirt system and Ford EDIS-4 ignition unit and am in the throes of a full EFI conversion. Presently fabricating the alloy manifolds and will be firing two injectors down the back of the manifold so the supercharger will only be pumping air. Holden Barina[Opel] throttle body.
 
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