Spring rates

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Mc Tool
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Spring rates

Post by Mc Tool »

What are the factory spring rates for a 2l 1980 MK3 Capri . I have looked about but the only thing I can find tells me the correct colour coding for the spring/car ( and there are a few ) .
I bought 2"lower, 145 lb springs for the front as at the time I had some notion that the stock spring rates were about 120lb....now I ain't so sure.
I also have to get single leaf springs made and have no idea what the rear spring rates are, so it's a bit hard to figure what to tell the spring maker guy.
Does anyone know what the standard rates are ? Thanks
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Andrew 2.8i
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Re: Spring rates

Post by Andrew 2.8i »

Mc Tool wrote: Tue Dec 17, 2019 9:10 pm Does anyone know what the standard rates are ? Thanks
The rates for the standard springs can be found on this thread

viewtopic.php?f=13&t=12390&p=88826&hili ... tes#p88826

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Mc Tool
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Re: Spring rates

Post by Mc Tool »

Thanks for that Andrew . Looks like my 145lb springs will be about a 50% increase ,which is more than I would have gone for , bit dumb really as I just saw them in Burton's catalogue ,decided that the 190lb ones would be to much boing and just assumed the 145's would be the "fast road" ones . So I'm lookin at about 170lb's for the rear. I hope the single leafs will stop it swingin it's arse about . I was thinking a 4 link for the rear but I ain't fussed on making changes that can't be undone (like cutting bits off or welding bits on ) so I can return the car to original if I want .
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Bug
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Re: Spring rates

Post by Bug »

Don't forget that your original springs will have sagged a little.
Reducing the gap between the coils can significantly retard the shock absorbing effect :poke: :xd:
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Re: Spring rates

Post by Mc Tool »

I'm stuck with the front springs but I figure if I get the spring man to make the back 1" lower than normal I can add lowering blocks to gain a bit more if I need it. :xd: You can calculate the correct distance between coils by measuring the resistance :lol:
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Bug
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Re: Spring rates

Post by Bug »

Just a thought regarding your rear springs.

Years back (around 1990) a friend and I with identical 2.8i Specials, both lowered the front ends using 175 lb -1" springs.
I also fitted 1" lowering blocks on my rear springs. My friend did not.

Before the change, our two cars had exactly the same ride height and stance.
After the changes, the cars still looked identical, albeit an inch lower.
Carefully measuring showed that my car was less than a quarter inch lower at the back than my friends was, even though I had the blocks on.
It appeared that, maybe due to weight distribution etc (who knows?), the rear of the Capri tends to follow the front down to a certain extent.
At this point in time, both cars were only 4 years old and relatively low mileage, so the springs should still have been in good condition.

To relief any excess strain on my car, I then removed the lowering blocks and my car stayed at the same lower level as my mate's one.

So, in short, I would recommend fitting lower front springs first and seeing what happens.

If your rear leaf springs are old and saggy, then yes, you'd maybe need to replace them. As far as I remember, single leaf springs on a 2.8i were 1" lower as standard, so fit them first and see how it looks. You can always get them re-tempered to bring it lower later on.
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Re: Spring rates

Post by Mc Tool »

I want to change rear springs as they are 40 years old and I'm thinking that the single leaf springs will be better coz there won't be any striction between leaves and I'm hoping that the single leaf ( with all poly bushes and spring mount ) will stop the car from swinging it's arse round so much . Maybe need a panard rod or a watts linkage
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Re: Spring rates

Post by 340truck »

Single leaf rear with axle location kit, X or A frame will get the arse wiggling under control
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Re: Spring rates

Post by nigecapri »

Agree with 340truck's post here. I have an A-Frame on mine, always have on my Capris. It is THE best modification by far before anything else, the car will handle better & thus be able to corner faster.
I recall reading somewhere that the Pinto 'S' models had uprated front springs @ 130lbs - Possibly part of the 'S' package to justify the extra cost?
My first set of performance front springs were 145's and suited the a 2.0 well, firmer cornering / less nose dive on braking but not rattling your bones ( I do recall having to drive somewhere whilst still suffering a severe bout of flu & due to the weight & fluid loss I COULD feel my bones rattling - never again.)
To slightly lower the rear end, loosen the rear anti-roll bar mounts to the chassis, get a heavy acquaintance to sit on the back then re-tighten the anti-roll bar / sway bar mounts.
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T.M.
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Re: Spring rates

Post by T.M. »

Hi,
2.8i front springs rate is 122 lbs/in. So 130 lbs/in for standard springs on lighter Pinto sounds too much for me.
And in this thread is for "new S" 102 lbs/in:
viewtopic.php?f=13&t=12390&p=88826&hili ... tes#p88826
But I don't know it exactly, just guessing.

If anybody wants, here is good link:
http://www.a400mod.com/VHK494S.htm
In the middle of page there are articles by John Miles. In Chassis engineering article (August 1983) there is a lot of interesting information. ;-)


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Re: Spring rates

Post by stevemarl »

Thanks for that, the tech stuff is interesting.
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