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My Ampera just failed the MOT on a fractured coil spring. Vauxhall’s are saying about 4 weeks for one to arrive.
ive searched the net and find Opel Ampera available.
Does anyone know if this fits?
thanks
 

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Ampera aka IGOR
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Part number for rear spring is 22810673 for the Ampera and an Amazon search brings back one for the Gen 1 Volt at £41. eBay has them from Lithuania but price including postage is more. This photo for the one on Amazon is the same as one for sale at £45 on eBay
 

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Ampera aka IGOR
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Fronts have a choice of 2 part numbers so there may be a difference. 25992782 or 23448005. A used full front strut including spring for 25992782, again from Lithuania, on eBay but no sign of anything for 23448005 other than from the States.
 

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Ampera aka IGOR
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In which case it's part number 22810673 as seen here. This one on Amazon looks used but It might well just be dust and dirt. It does not mention location but the same photo is also on eBay for the same spring located in Lithuania.
 

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Front and rear springs are listed on gknautomotive.com for the Opel Ampera 11.2011 - 03.2015


 

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Ampera aka IGOR
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I would be very surprised if they were different between the UK Ampera and the UK Volt, maybe between the US Volt and the UK Volt due to different roads/handling preferences and softness of ride between the two areas.
 

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When I found stockists for the Volt coil spring and checked on the same database whether it was suitable for an Ampera, the database stated that it wasn't. Likewise with the Ampera coil. I did find the coil on eBay, but it`s now out of stock.

However, my local garage said the coil looked very similar to the coil used in a Vauxhall Combo van. When they checked, it was a perfect match so that's what they fitted. I'll post the part details later,
 

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"Looks similar to" just doesn't cut it with coil springs. They are very sentitive to small changes in the diameter of the original wire used to wind them. You'll find the formula for the stiffness here:
How To Calculate Spring Rates – How To Adjust And Tune – Suspension Secrets
D is the (large) diameter of the spring, measured from the centre of one "wire", across to the centre of the opposite side. So slightly smaller than the diameter of the smallest baked-bean tin needed to enclose the whole thing. But this is the easy one to measure, spring simply won't fit in if you get this too large or small.

Far more subtle is the diameter of the wire, 'd', and the stiffness is proportional to the 4th power of this! What does this mean? Well, if you buy a similar-looking spring that has the wire 10% larger in diameter, the stiffness will increase by 1.1 * 1.1 * 1.1 * 1.1 = 1.46, so nearly 50% stiffer! Apart from making the ride hugely firmer, it also means the ride height of the car may be a lot higher than expected, as this spring will compress far less when you take the car off the jacks.

If possible, you should get the precise details if that spring before paying for it. It will need a micrometer on the wire used to get an accurate value of 'd', similarly for the present Ampy spring, and you want the number of coils & the free length as well. This is assuming 'D' matches as well.

Armed with that formula, it's not hard to put it into a spreadsheet, and knowing the weight of the car it's not hard to calculate how much the spring will compress when lowered off the jack. Then the ride height will be the Free length - the amount it compresses under load, and yuo want that to match the existing spring values.

I once stiffened up a very soggy Volvo 360 by going down to local spring stockist, and rummaging through the boxes until I found a suitable replacement. I found a set for Ford Capri Rally fitted well, after I'd chopped 1 turn to get the ride height correct (which made them even stiffer of course! The car cornered on rails after I'd swapped the old ones out. I forget what the stiffness increase was, but it was large, at least 50% stiffer I think. But that car was excessively roly round bends...
 
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