Rear Coilover Springs

[Mike]

Has anyone fitted coilover springs to the Cabrio rear suspension?

My rear spring seats are fully adjusted to the top, and I still have too much clearance between arch and wheel, so will probably have to buy new springs. And if I'm going to buy new springs I'd like to consider coilovers, if they are an option?

What spring rate does anyone recommend for a Cabrio/Hunter?
Mike

[dogoncrazy]

Re: Rear Coilover Springs

Mike
I would wait till it all settles down after you've driven a few thousand miles then you may find it more acceptable.

[CosworthCabrioLee]

Re: Rear Coilover Springs

Mike I would not get hung up on filling your rear arches , you are best leaving some daylight and you can paint and detail under there, with stainless screws. it also makes cleaning much more easy.

[chris_cussen]

Re: Rear Coilover Springs

I've a fairly large space between the top of the wheel and the arch, but with 15" rims and an exhaust exiting at the rear it scrapes its exhaust occasionally. On the way to work there are a couple of dips in the road with a slight hump down the middle of the road caused by heavy lorries compressing the road surface, and this is where it bottoms out.

So if you try to fill your wheel arches by lowering the car just watch out it does not reduce the ground clearance too much.

[Robert in Cumbria]

Re: Rear Coilover Springs

I agree with Dogoncrazy, It's something you can address once the car has had some real live use, I think the clearances will have been thought out pretty well and I would say what you are seeing is the expected gap.

You will have plenty of time to make adjustments and fine tune ride heights, once the car is on the road. Go for standard and fine tune later, if you feel the need.

[Mike]

Re: Rear Coilover Springs

Thanks for the replies.
The clearance above the arches is something I have a pet dislike on Cabrios generally.
I have deliberately installed my fuel tank 25mm higher, and chosen oval (read thin) exhaust silencers to improve ground clearance to the max. I have also fitted the rear arches 20mm lower than Marlin suggest, and I have left the top part of the wheel arch 5mm deeper than the sides. I have now adjusted the spring stops fully to the top and yet I have still ended up with this:- its at least 25mm more than I would have liked!

IMG_0868(2).jpg

[lizbillings]

Re: Rear Coilover Springs

I suggest you get it ready for test and then fettle it. Regards Liz

[Robert in Cumbria]

Re: Rear Coilover Springs

Mike, I suspect the fuel tank is empty and there are no occupants in the car. I can see what you mean but I would concentrate on completing, as you are, providing for lowering later. I would bet it will settle at least a bit after it's been used.

Unless you need to make fundamental changes to fit coil over units, then of course you should at least make provision for that. Is it not possible to shorten or fit softer rear springs?

[Mike]

Re: Rear Coilover Springs

.................Unless you need to make fundamental changes to fit coil over units, then of course you should at least make provision for that. Is it not possible to shorten or fit softer rear springs?

.....which brings me back to my original question!
I do not know if/what changes are required to fit coilovers, (if they are not significant I may choose to give myself the option in the future) but maybe no one has gone down this route?

[cabrioman]

Re: Rear Coilover Springs

Mike

Just for info. I have a set of brand new Sierra springs which I used on my original Cabrio build. When rebuilding the suspension onto my Hunter last week I compared them to the original springs on the Hunter. Both sets of springs had the same green colour coding but the Hunter springs are shorter by about 50mm. They look like they have been cut down with a plasma cutter, they are definitly phyisically shorter not just settled. It makes me suspect Marlin modify the springs when they are building to reduce the ride height. I have gone with the shorter Hunter springs.

John

[Robert in Cumbria]

Re: Rear Coilover Springs

For a car to be subjected to an IVA are cut down springs not taboo? I would have thought that properly forged spring ends would be required. Even heating and allowing the springs to collapse slightly can be a fail for the MOT so I would have thought the IVA would be more critical.

Perhaps another thing better kept for post IVA mods?

[cabrioman]

Re: Rear Coilover Springs

Not sure cutting a spring constitutes an MOT fail, no indication in the MOT testers manual see below:

2012
Information

Where a coil spring is incomplete, cracked or
fractured at an extreme end where the spring
locates on the spring mount, it should only be
rejected if:
• the function of the spring is impaired
• following jacking, the spring ends do not
locate correctly when the vehicle is lowered
into the normal running position without
assistance
These criteria should also be applied to springs that
have been deliberately shortened or modified in
order to lower the suspension.

C. Coil Springs
1. Visually examine each coil spring for general
condition. In particular, look for cracks or
fractures.
2. Check that both ends of the spring are correctly
located.
3. Check that the spring mountings are:
a. secure
b. free from cracks and fractures
c. free from excessive damage or corrosion.

Reasons for failure

1. A coil spring:
a. incomplete, cracked or fractured
b. worn or corroded so its cross sectional area
is reduced such that it is seriously
weakened.
2. A coil spring not correctly located.
3. A coil spring mounting:
a. loose
b. cracked or fractured
c. seriously weakened by damage or
corrosion

Not checked IVA but I can see no reason why it would be different to the above.

John

[Robert in Cumbria]

Re: Rear Coilover Springs

Incomplete?

I guess provided the spring is still tight, ie not lose, when the wheel is lifted clear of the ground it may be Ok but the spring would need to be seated properly in those circumstances, which is why they are forged at the ends. Simply cutting a coil back by 60mm won't make a sound spring seat.

[Mike]

Re: Rear Coilover Springs

Mike

Just for info. I have a set of brand new Sierra springs which I used on my original Cabrio build. When rebuilding the suspension onto my Hunter last week I compared them to the original springs on the Hunter. Both sets of springs had the same green colour coding but the Hunter springs are shorter by about 50mm. They look like they have been cut down with a plasma cutter, they are definitly phyisically shorter not just settled. It makes me suspect Marlin modify the springs when they are building to reduce the ride height. I have gone with the shorter Hunter springs.

John

Hi John

Thanks for this info - I guess it confirms what I suspected. I'm not sure what route I will finally take - on the one hand I can appreciate the "wait and see" argument - I am sure the rear end will settle. Conversly there must be 50mm of adjustment on the spring seat, and with it fully wound up, I still have too large a gap.
Starting with springs 50mm shorter sounds about right for my chassis set up, and even if they settle, I'll have 50mm of adjustment available to soak up any settlement.
I think I may just cut a set of springs down to see what they are like, and if they seem ok, I could then get a proper set made?
Thanks again for the valuable feedback.

It would be really interesting to know whether other Hunter owners have the same spring set up?
Mike

[cabrioman]

Re: Rear Coilover Springs

Hi Mike

Just to add, 50mm was my rough estimate, don't take it as exact. Its at least 40mm though, I can take exact measurements if you need it. Looking at the colour coding both sets are original Ford springs. The Hunter springs have been cut but there is no forged ends on the other uncut springs so other than looking shorter the Hunter set are exactly the same in terms of profile of the spring seat etc.. They definitely have not been cut with a hacksaw, it looks more like a plasma cut, unsure of course if they were reset in terms of hardness but the powder coat looks original over most of the spring so I suspect not.

Attached is a picture of my Hunter on its original springs running 15 wheels with 195/65/15 tyres. I am going to go to 17" wheels as per SimonG but I intend to just adjust the spring seats if needed.

As a side note there are lots of listings on ebay for lowered sierra springs, might be worth a look if they are lowered by the amount you think you need.

John