36 DCD tuned and ready

The Weber 36 DCD has been tuned and installed, main jets 135 air jets 200 idle jet 50 with 25mm chokes
The head was match ported to the manifold, the choke was removed and a custom throttle lever was fabricated. Make no mistake this engine is fully capable of suking al the air and gas this carb supplys!

Rough specs here:
903 engine
PBS ralley cam
balanced and lightened flywheel and pressure plate
Weber 36/36 DCD carb
S/T cam gears
9.5? compression ratio
Fiat 127 water pump
Fiat X19 electric cooling fan
Flipped top spring in front to lower car
Cut rear springs new shocks
850 front disk brake conversion
Fiat 124 spider steel rims with RE potenza 165-65=13 tires
I will pull the engine soon to change to front main bearing seal to the reverse rotation style
Also hope to auto cross/solo this summer in the under one litre group

Fiat 600's new mirror

Spider rear end

A couple of notes when changing to a early diff in a late spider, chase the lug bolt holes with a 12mmX1.25 tap, I used a L bracket that was custom bent to hold up the bracket where the hard brake line meets the soft line it bolts on to an existing 10mm nut on the diff case close to where the caliper bracket is attached, we decided not to use a backing plate giving better brake cooling? All the upper and lower diff locating rods are the same and bolt right up.

Rear ends

Mayuko's spider diff was making a lot of noise, terminal noise. We decided to go with an early pre 1978 style as a replacement.

Here are the parts you will need for the conversion:

*early complete differential with axles (don't forget the shock attachment ears)

* early style straight pan hard bar

*pre 78 back half of drive shaft (or not)

The most common gear ratio was 4.30 we found a 4.10 which is a little closer to the original 3.90 her spicer style diff came with.

You just unbolt everything and carefully slide out the old unit, her springs were cut so no need to compress them, and the brake lines will move out of the way after cutting the wire tape that attaches them to the housing. You don't have to undo any brake lines.

Fill the diff with oil while it's out we used 80-90 EP oil, about 3-4 pints or until it runs out the fill up hole.

We opted to use the original drive shaft which is about 10mm too short, just loosen the drive shaft center support bracket and slot the holes a little then tighten the rear drive shaft to the diff then tighten the center support bracket. It's about a three hour job if you have two monkeys working together.

Photos shall follow.

More DCD photos

Those with sharp eyes will see that I made a cover in place of the choke assembly and I had to make a new cover for the throttle assembly so the lever would clear.