Tunnel changes to fit an overdrive box

[j.fernie]

I have an 1800 TC based car to which I'm planning to fit an overdrive gearbox. The back of the "new" box is wider than the original and it isn't going to fit into the existing tunnel.
Was the tunnel factory fitted or was it a builder's option? Obviously its important as it supports both the floor and the back of the gearbox. Does it have any other critical functions? or can I make it whatever shape I like?

[dogoncrazy]

Re: Tunnel changes to fit an overdrive box

Jim
You can alter the shape without detriment. I believe various patterns were available to accomodate different engine /gearbox configurations on placing your order for the kit.Kits from YKC came with galvanised steel floors /tunnel and bulkheads as opposed to the original ally panels and ply floors of the earlier cars.

[j.fernie]

Re: Tunnel changes to fit an overdrive box

Alan,
Thanks for the info. I have an earlier car with an ali tunnel and ply floors, so it will all have to be modified to suit. I might look at replacing the floor as well as the tunnel since I've got to take it all apart.

[stevejgreen]

Re: Tunnel changes to fit an overdrive box

Or I have managed to fit a Ford Type 9 with no tunnel mods.
Useful as a SWB and me is a tight fit.

[andy4]

Re: Tunnel changes to fit an overdrive box

What sort of Overdrive box are you fitting ? Obviously if the length of the box is different you will need to mod the propshaft, as the propshaft angle then changes you need to think carefully about the height at which you mount the tail of the box etc.