Been focusing on gear linkage for the past couple of weeks after finding out from my fuel tank fabricator that the tank is going to be delayed a little due to his excessive workload.
All the traditional Elise engine swaps - FWD derived donors like Audis,Hondas, and Duratecs - have one thing in common. Cable shift gearbox linkages.
This means that with all the swaps getting the lotus gearlever to work with the new box is child's play, although depending on the donor 'box getting it shifting sweetly can be tricky.
The F355 box is rod change. This has some advantages and disadvantages.
Advantage No1 is feel, solid rod change linkages tend to have a positive precise feel to them, where cables can feel a little vague and 'stretchy' sometimes. The F355 shift in the Ferrari is reckoned to be one of the best manual open gate gearchanges in a road car and if I can get it 80% as good in mine I will have done well.
The main disadvantage (along with increased weight) is the reduction in flexibility for packaging. In order to get the rod linkage to work you need line of sight, and not only that but if the rod-spans are excessive you need additional sliding supports.
With all this in mind going for the F355 original lever linkage rather than trying to design some custom conversion for the Lotus lever was a no-brainer!
I needed 3 sections of rod, so 4 universal heli-joints. Luckily none of the joint angles were excessive.
Squeezing the rod between through the original cable space was tight but just about achievable.
For support I used bronze-bushed rod ends as these generally have a ground ID with a good tolerance and surface finish.
To mount the housing in the cockpit I used some 3mm aluminium U channel.
Hopefully within the next week I will find out if it works (with a static engine).
The open gate is an aftermarket "slick shift" billet item with improved quickshift gate angles. The F355 owners seem to rate them so I gave it a go.
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