Steering Wheel Conversion
Original Nardi to Aftermarket Momo
This guide shows you how to fit an aftermarket Momo steering wheel to an Esprit with an original Nardi steering wheel. This was done to fit a Momo wheel with a flat bottom to give more room for the drivers legs. This conversion required an adaptor to attach the steering wheel to the original boss.
The Nardi to Momo boss adaptor was purchased from an ebay shop. It is a 10.5mm thick aluminium ring with 'Nardi spaced' countersunk holes, allowing it to be attached in place of the existing steering wheel. It also has M5 tapped holes with 'Momo spacing' to allow a Momo style wheel to be attached. The outside of this particular ring is painted black so it is inconspicuous when fitted.
The inside diameter of this adaptor was 55mm. To fit the Esprit's boss this needed to be opened up to 60mm, which was also the correct diameter to allow the horn ring to be inserted. The horn ring is attached between the adaptor and the steering wheel, and allows the fitment of a horn button (which is being used for cosmetic purposes only in this installation).
It would be a simple job for any machinist to make an adaptor of this type, but given the low cost of this item it made good starting point
This is a fairly simple install and should take around 10 mins to do if no modification is needed for the boss adaptor.
You will need the following parts:
to Momo boss adaptor
You will need the following tools:
and 4mm allen keys
Remove the crash pad from the steering wheel. This is held in place by rubber 'wings' and simply pulls off. This reveals the six countersunk screws that hold the existing wheel to the boss.
Unscrew these with a 3mm allen key. The wheel will now pull away from the boss.
The boss adaptor should now be attached in place of the old wheel using the original screws.
The new wheel may now be attached to the adaptor, remembering to sandwich the horn button ring between the wheel and the adaptor. The Simoni wheel is not countersunk like many wheels, so cap head screws were used. I wanted black, and managed to source High Tensile black M5x16 cap head screws from Modelfixings.co.uk. Do Not use Black anodised aluminium screws that I found more easily available. Luckily, the boss is recessed at the positions of the new wheel mounting screws, allowing M5x16 screws to be used which would otherwise be slightly too long.
All that is left is to fit the horn button. The button should push in place, but the threaded end of the steering column protruded too far into the horn ring to allow the button to be inserted fully. This was quickly resolved by removing a 20mm diameter area from the centre of the back of the horn button. This horn button was hollow in the centre apart for the electrical contact (which was not required), so removing this was not a problem.
If making a boss adaptor from scratch, an ideal thickness would be around 16mm to allow a horn button to be used without modification.
A vinyl lotus sticker was used to cover the horn button, which was then pushed in place to finish the installation.
by Russell Bosier
My main aim was to gain extra height between the driver’s seat and the steering wheel. This was achieved in 2 ways. The presence of the adaptor extends the steering column upwards slightly providing a little extra space, in addition to the space gained by the flat bottomed steering wheel. Along with this and the updated look, there was also the unexpected bonus of being able to see more of the speedo from my seating position.
The down side of converting to a Momo fitment wheel is finding a suitable adaptor, if you do not want to modify, or make one from scratch.
This mod was performed by Russell Bosier on his 1989 SE
If you have any comments, feel free to e-mail LEW at firstname.lastname@example.org