Coil Springs.

[Rogue Trooper]

Just be aware that aside from the safety issue around cut springs you are going to screw the camber on the front of your van as well as the toe which means you are going to go through tyres like nobody's business. The toe can probably be fixed with a wheel alignment but to fix the camber issue you are going to have to spend serious dollars and make a number of modifications.

[Numnutz]

Yeah I understand the issues with the camber. If it wears tyres really quickly, I’m going to have a go at moving the lower wishbone.
The lower wish bone is only held on by 4 small bolts either side. (Remove, weld up holes, drill new holes, reinforce, bolt back up) should almost be easy.
Just have to do some good maths, to calculate the right place to drill.

From what I understand about springs, cutting them is not really a safety issue, as long as they have not been heated.
(I.e. giving springs a blast with the oxy until they sag to the desired height.) Big no no.

I read a detailed engineering article somewhere; it was saying the ride characteristics of the spring should almost be exactly the same,
As the coils per inch and diameter of the spring have not changed.

once I get it done, I'll let everyone know how it goes,

[BusyKiwi]

if you move the wishbones you'll be putting more strain on the tierod ends so really need to shorten your steering rack too
the tie rods will thread in further but the more you do the less adjustment you'll have ....

[Rogue Trooper]

From what I understand about springs, cutting them is not really a safety issue, as long as they have not been heated.
(I.e. giving springs a blast with the oxy until they sag to the desired height.) Big no no.

Bear in mind that the top and bottom of the springs form a flat plain that allows the spring to sit flat in its seats. When you cut them you are going to lose that flat seating at the top or bottom which will mean that the spring doesn't sit properly and will no longer be properly captive. That's your safety issue.

[Jeff]

I read a detailed engineering article somewhere; it was saying the ride characteristics of the spring should almost be exactly the same,
As the coils per inch and diameter of the spring have not changed.

Not quite. The shorter spring will effectively be stiffer overall = Harder ride.
Because for a given load, each coil in a Bedford compresses by the same amount,
So less coils = less total compression.

[Merlin]

The shorter coil being stiffer is not entirely true as the load remains the same on the spring the weight is dispersed over the coils (think of 10 blokes lifting a car as opposed to 8 blokes they will still lift it but they have to work harder) and you will suffer coil bind much sooner due to the shorter travel  hope that clears it up for you    Cheers Neil

[ben]

is coil bind when the coils all touch each other/ bottom out?

Quote from: Numnutz on Today at 07:18:03 AM

From what I understand about springs, cutting them is not really a safety issue, as long as they have not been heated.
(I.e. giving springs a blast with the oxy until they sag to the desired height.) Big no no.


Bear in mind that the top and bottom of the springs form a flat plain that allows the spring to sit flat in its seats. When you cut them you are going to lose that flat seating at the top or bottom which will mean that the spring doesn't sit properly and will no longer be properly captive. That's your safety issue.

only the top forms a flat plain. the bottom is not flat. but is still slightly different to the centre of the spring so rouge has a point. althou i know of people that every van they have ever owned they have cut srings to lower front just a little for the last 20 years..

here is pics to show of a standard spring.

[Jeff]

Merlin, if the spring was stretched out into a bar, it would display the same *springyness* as a coil.
And if the bar spring was one meter long and a weight hung off the end, it would drop X amount.
But if the weight was moved to 500mm it would only drop half of X.
(The graph of a spring , load vs movement is a straight line until the elastic limit is reached.)
Therefore the spring would be stiffer.

I lowered a Cortina in my youth by chopping the coils and the ride was noticeably harder.

[Rogue Trooper]

only the top forms a flat plain. the bottom is not flat.

Hmmm, from memory both my ends were flat although admittedly my memory is pretty crap. Mine are coming out again shortly to be reset and retempered to bring my ride height down to normal before we fit the power steering rack so I'll take a look then.

[Jeff]

The bottoms on mine are as Ben says. This can be seen by looking underneath the bottom wishbone.
You can see the helical spring seat.
Rouge, you may have non standard springs!