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[GrahamK]

This may be a daft question- go easy

I've got a new pair of Sachs springs for the front of my car. From reading the forum, I understand that UK cars had equal length front springs, but I could not find a named pair of springs like that for sale.
I got the Sachs ones and they are different lengths. They are marked as Right and Left, with the left one the longer.
As my car is RH drive should I consider changing the longer spring to the drivers side? or there other weight/loading issues that determine it should remain on the left?
The car is a 2.6 CDX saloon.
Any thoughts much appreciated.
Graham.

[Nick W]

This may be a daft question- go easy

I've got a new pair of Sachs springs for the front of my car. From reading the forum, I understand that UK cars had equal length front springs, but I could not find a named pair of springs like that for sale.
I got the Sachs ones and they are different lengths. They are marked as Right and Left, with the left one the longer.
As my car is RH drive should I consider changing the longer spring to the drivers side? or there other weight/loading issues that determine it should remain on the left?
The car is a 2.6 CDX saloon.
Any thoughts much appreciated.
Graham.

Realistically, I doubt you'll ever notice a difference. But as it makes no change to the work, put the longer spring on the driver's side

[GrahamK]

Thanks Nick,

Interestingly, I've just checked the old springs which clearly are GM (brown Spots) and they are unequal lengths. Sadly, I don't know which was fitted where. DOH!

I don't wish to over complicate this, but the battery is pretty heavy?

Regards,

Graham.

[Nick W]

Thanks Nick,

Interestingly, I've just checked the old springs which clearly are GM (brown Spots) and they are unequal lengths. Sadly, I don't know which was fitted where. DOH!

I don't wish to over complicate this, but the battery is pretty heavy?

Heavier than you are?    The other side has the airfilter and coolant tank, which can't be much different to the battery.

[GrahamK]

I'm definitely worth a few batteries.

[Doctor Gollum]

Drivers side makes sense, although left hookers definitely need it as they've battery AND a fat german... 

[johnnydog]

Without throwing any proverbial spanner in the works, a longer spring doesn't necessarily mean it is firmer or a stronger spring.
Inconsistant spring wire diameter, number of coils and spring poundage are all factors.
Front springs on the Omega iirc are a contant spring wire diameter, which eases the headache slightly.
To maintain a constant ride height between left and right with different springs lengths, the lb2 of the two springs needs to be established.
In my experience, a firmer spring giving the same ride height, has a different numbers of working coils, or a thicker wire diameter - invariably a firmer spring is shorter in length as it doesnt compress as much.
With varying spring lengths, the aim is to have a level ride height - left and right.
If there is an increased load on one particular side, then that side needs to be the firmer of the two. If the coil diameter, and number of working coils differs on each spring, then you can't simply go off the free length to establish which is the stronger spring.
I am surprised that there isnt more manufacturers clarity regarding their fitment  with LHD or RHD vehicles as there obviously is a difference, but I personally would do some more checks prior to fitting. Like I say, a longer or shorter spring doesn't necessarily indicate a stronger or softer spring.
If you are certain that the only difference between the two is the free length, and the wire diameter is identical, the number of coils over the two lengths on a pro rata basis is correct, you could logically then assume that the longer spring is the firmer, but there is a lot more to it than just the length and number of coils in detetmining a springs strength.
As far as I can tell, the correct UK spec springs for your 2.6 from Vauxhall are part no. 90541754, which come as a 'set', and therefore ought to have markings to indicate LH or RH.
Just my thoughts....

[LC0112G]

As far as I can tell, the correct UK spec springs for your 2.6 from Vauxhall are part no. 90541754, which come as a 'set', and therefore ought to have markings to indicate LH or RH.
Just my thoughts....

The RHD 'sets' have two identical springs, so it doesn't matter which way around you fit them.

It's the LHD 'sets' that have two different springs, and therefore on a LHD car it matters which one goes where. Aftermarket spring sets appear to be primarily aimed at the European market, and therefore have two different springs.

When I did mine I purposely bought two identical springs rather than fit different euro-spec ones.

[johnnydog]

From a simplistic point of view, I have never understood why the front spring rates should vary from LH and RH.
Graham states he understood UK spec cars were the same spring; this makes perfect sense in reality, and that it was only LHD vehicles that had different springs fitted for whatever reason.
The weight of a battery, a 'fat German' (not my words ) or any other component ought not make any noticable difference on a cars suspension. The engineers at the time must have had their reasons, but I would suggest the differences are minimal. If it was that critical, then surely there would be strict guidance on how (or not to) load a vehicle in the handbook, as it doesnt take much to add a similar weight to any or all of these 'components' in any car. The only possible exception to this in the handbook being the reference to tyre pressures when loaded.
I'd be inclined to fit a identical pair rather than faff around worrying whether the correct spring is fitted to either right or left.
The strut body is surely the same dimensions left or right, so it shouldn't theorectically be an issue fitting identical springs imho.

[Doctor Gollum]

There's a more weight on the left of an LHD Omega...

You've the steering box and brake servo, and add in the battery that's actually quite a lot more weight relatively speaking.

On a RHD car the brakes and steering box is offset by the weight/position of the battery.

The geometry assumes that weight of load (passengers/cargo) is spread evenly by all four corners

[Doctor Gollum]

Had the question been asked prior to ordering parts, then the advice would have been to fit a pair of identical springs to the front, and the hassle of returning the purchased pair notwithstanding, that would still be the ideal course of action. 

[Nick W]

From a simplistic point of view, I have never understood why the front spring rates should vary from LH and RH.

I'd be inclined to fit a identical pair rather than faff around worrying whether the correct spring is fitted to either right or left.
The strut body is surely the same dimensions left or right, so it shouldn't theoretically be an issue fitting identical springs imho.

You're not thinking like a German engineer.


They will have weighed each corner, noted that there was a 11.67847474588kg difference(approx) between the fronts, and calculated the tiny difference required between the two spring rates. Having worked all this out, it would be impossible for them ignore it, as fitting identical springs wouldn't be technically correct. That it requires another set of springs with a load of production consequences is irrelevant.


Anyone else would have fitted two identical springs, looked at the car from the other side of the workshop, and called it done. Which is how most cars are equipped.

[GrahamK]

Thanks for all the comments.
I did set out to buy  matched pair of springs but when I ordered them a few months ago, I could not find a pair for sale from A known "named" manufacturer.
This is why I went for the Sachs ones. This does leave me with a decision to make.
Although, I was surprised when I checked the original Springs that I have just removed and they are clearly the original fitted by Vauxhall and they are different lengths.

I am beginning to wonder whether the idea of UK spec cars having same length springs is a myth. I can certainly imagine pattern part makers would decide on a single spring type for both sides as it clearly makes the stocking and selection much easier. Certainly a number of people in this thread have said they doubt it will make much difference.

I would be interested to hear of any hard evidence that the UK cars had same length springs? Mine certainly didn't.

Regards,

Graham.

[LC0112G]

Thanks for all the comments.
I did set out to buy  matched pair of springs but when I ordered them a few months ago, I could not find a pair for sale from A known "named" manufacturer.
This is why I went for the Sachs ones. This does leave me with a decision to make.
Although, I was surprised when I checked the original Springs that I have just removed and they are clearly the original fitted by Vauxhall and they are different lengths.

I am beginning to wonder whether the idea of UK spec cars having same length springs is a myth. I can certainly imagine pattern part makers would decide on a single spring type for both sides as it clearly makes the stocking and selection much easier. Certainly a number of people in this thread have said they doubt it will make much difference.

I would be interested to hear of any hard evidence that the UK cars had same length springs? Mine certainly didn't.

Regards,

Graham.

The lengths after 20 years on the car is a mute point. No way of knowing if either or both have sagged, and if they have by how much.

The evidence is two fold.
1) Both the springs that came off my car carried brown-brown paint marks, as described in Haynes.
2) Haynes describes the markings, lengths and spring rates for RHD cars. I assume they got this info from Vauxhall/Opel/Gm sources.

Did the springs that came off your car not have paint marks? They seem to survive quite well.

[Nick W]

The lengths after 20 years on the car is a mute point. No way of knowing if either or both have sagged, and if they have by how much.

The evidence is two fold.
1) Both the springs that came off my car carried brown-brown paint marks, as described in Haynes.
2) Haynes describes the markings, lengths and spring rates for RHD cars. I assume they got this info from Vauxhall/Opel/Gm sources.

Did the springs that came off your car not have paint marks? They seem to survive quite well.

That's almost exactly what I was going to post, although I wouldn't have hedged with the if. Measuring the ride height usually proves this; some stock(albeit cheap) new springs brought the front of my 180,000 mile car up by 30mm and stopped it being the wallowing pig that it had been. Lots of Some people replace shocks, but they rarely change springs unless the things are actually broken.


You can test what they are now, with some bathroom scales and a press. That's only really useful if you're intending to order some custom springs.