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Running cables, brakes, etc under car
pezzer - 19/10/11 at 11:56 AM

Hi,

I'm building a kit (sdr vstorm - rear engine) and am considering running cables, brake pipes, clutch pipe, accelerator cable, etc all on the bottom of the car which is completely flat. Other people have run them through the chassis tubes, but I'd rather avoid this as it's complicated, and means you can't get at anything once it's in.

Obviously I need to protect the cables/pipes, so I was thinking of sticking them between two one inch box sections, and putting a cover plate over. Does this sound sensible? Anyone got any better ideas?

What metal would you suggest for this? I was thinking of using aluminium as it wont rust, and will save weight. But will it be strong enough?

britishtrident - 19/10/11 at 12:11 PM

If you don't have a tunnel they should go through the interior, either along the sills or in a small tunnel on the inside.
You will also need to run heater pipe work through the interior.

adithorp - 19/10/11 at 12:30 PM

quote:
Originally posted by britishtrident
If you don't have a tunnel they should go through the interior, either along the sills or in a small tunnel on the inside.
You will also need to run heater pipe work through the interior.


How is a heater going to be of any use in this ?

But I'd agree inside would be better. Your idea of two box sections and a cover would work I suppose in creating a mini tunnel for them, but I'd prefer them inside clear of speed humps etc.

jossey - 19/10/11 at 02:06 PM

r u mad.

what if you hit them on a speed ramp or something....

wont you lose brakes, water, electrics ETC

pezzer - 19/10/11 at 02:26 PM

quote:

but I'd prefer them inside clear of speed humps etc.


This was my first thought. But then I realised the handbrake and gear linkage both run along the bottom, so the problem will already be there.

As cables/pipes wont stick out as much as them, is it really a problem to run them underneath in another smaller tunnel?


quote:

How is a heater going to be of any use in this ?


Indeed. Although, one of those neck heaters from a merc would be nice

pezzer - 19/10/11 at 02:34 PM

quote:
Originally posted by jossey
r u mad.

what if you hit them on a speed ramp or something....

wont you lose brakes, water, electrics ETC


Hence why I was suggesting making a tunnel! Most cars run brake and fuel lines underneath them. Usually in a raised but exposed section of the floor-pan. I did manage to hit the o2 sensor on my civic on a speedbump once, and that killed the car (grazed the cable, shorted it, blew a fuse that operated the dash, which in turn knocked out the alternator!)

foskid - 19/10/11 at 02:34 PM

Absolute lunacy to put them under the floor, if you can't put them in the chassis tubes why not fabricate a conduit on the floor using alloy angle/sections, make it with a removable cover so you can have them safe and access. Shouldn't be to complicated.

Cheers, John

pezzer - 19/10/11 at 03:43 PM

I'd agree that it's absolute lunacy if they're unprotected. But is still going to pose a problem if I run the cables between two box sections, with a cover over them? Surely this is close to the same protection they'd be getting above the floor. Sorry for re-asking the question, I just wanted to make sure you didn't think I meant exposing them.

My only reason for wanting to do this is that this is the simplest option. The floor is flat underneath, but there's some small box sections on top. In order to run along the car, I'd have to run the pipes/cables above this box section, raising the floor well up in the car. It's a three seater, so that'll under the drivers seat (if it'll fit). The sills are an option, but i'm not sure where they'll go round the back seats (don't have the grp yet to check), so that's going to hold it up further.

One question about running them in the chassis tubes - they won't be fixed. Aren't electrics/brakes meant to be fixed at particular intervals?

Island - 19/10/11 at 04:05 PM

Make sure regulations alow you to run fuel pipes thru the cabin, i think that is the main reson they are run under all cars.

Mal - 19/10/11 at 04:48 PM

If it helps facory built Westfields run fuel pipes on the underside of the floor.
Many Westfield self builders take them through the tunnel.

pezzer - 19/10/11 at 05:18 PM

The car is rear engined, so no fuel pipes. It's just brakes, power (battery is at the front), accelerator, clutch, wiring.

Mr C - 19/10/11 at 05:32 PM

I'm presuming its Dan, Hi Dan if it is and apologies if not. Jeremy and myself looked at all the options and for the sake of neatness went for the tube install either as far as the rear bulkhead then let the cables etc out there or ran them into the car further forward and then ran the cables etc down the sill sides where they can be fixed.

Jeremy ran all of his through the bottom rails and let them out into the sills once in the forward part of the cabin. I did the same but also ran stuff through the top pipes the whole length to the rear bulkhead. Its not as difficult as it sounds especially if you preassemble looms etc and use electricians rods. Where pipes etc are enclosed in a conduit they don't need to be fixed. If you go the tube route then once completed it may be worth filling the tubes with expanding foam or something similar to stop any rattles What goes in them shouldn't go wrong either The other option is to bolt a U channel down the middle of the underside from front to back and run everything in there. On the demonstrator It added no more than 20-30mm

Unfortunately to a certain degree the car has been designed with form over function in mind so there is no easy way of fabricating something in to the floor.

There is no wrong or rights with whatever way you choose. All the best with it

AntonUK - 21/10/11 at 05:32 PM

In my mini days, The standard car had the main battery cable & brake lines along the underside of the floor. Once it was lowered a bit and bigger exahaust added the battery cable was always getting smacked but brake lines were ok until its was very low.

But if we ever re-ran brake lines for any reason we would run them in car to save them from the elements.