Helper springs

[jimmystratos]

Above or below the main springs?

[GreenV8S]

Above seems conventional.

[B19GRR]

Or possibly below:
www.compbrake.co.uk/suspension4.htm

Eeek! I can't believe I'm disagreeing with Peter!! Possibly it depends on strut type. On MacPhersons I've definitely have them at the bottom so the helper spring platform was over the main body of the strut.

Cheers,
Rob

[jwb]

I would fit the helpers at the top to get the lowest C of G possible.

John

PS Every bit helps with C of G, I even think about which way i put nuts and bolts to get the lowest C of G possible.

[GreenV8S]

jwb said:

PS Every bit helps with C of G, I even think about which way i put nuts and bolts to get the lowest C of G possible.

Have you added up the total difference to CoG height from every nut on the car? I'm usually more concerned about whether I'll be able to get at it when everything else is put back around it, and whether the bolt can rattle itself out if the nut comes loose.

[jimmystratos]

B19GRR said:

Possibly it depends on strut type. On MacPhersons I've definitely have them at the bottom so the helper spring platform was over the main body of the strut.

Cheers,
Rob

I'm thinking about inclined front coilovers.

Thanks for the replies, guys!

[jimmystratos]

When I mount the helper spring, the adapter that joins the helper to the main spring hits the collar before the helper is coil bound. This doesn't seem right. Comments?

[GreenV8S]

jimmystratos said:

This doesn't seem right.

Agreed.

[Sam_68]

No, that's fine...you wouldn't want the helper spring going coilbound.

Even if the seat for the helper is in contact with the main spring seat, the helper is still pushing back against the main spring, via the helper seat. That's the way it's supposed to work.

[GreenV8S]

Sam_68 said:

No, that's fine...you wouldn't want the helper spring going coilbound.

Helper springs and tender springs are designed to cope with being coil bound. In fact helper springs are designed to be coil bound most of the time and only open to stop the main spring coming unloaded in droop. Having a mechanical stop that prevents the helper from becoming coil bound isn't immediately harmful, but my concern is that the spring seat and adapter plate aren't designed to bear against each other and might become damaged. It will *probably* be OK but it is not how these springs are designed to be used.

[Sam_68]

GreenV8S said:

...helper springs are designed to be coil bound most of the time and only open to stop the main spring coming unloaded in droop....it will *probably* be OK but it is not how these springs are designed to be used.

Agreed, helper springs can be designed to be coil bound most of the time, but it looks to me as though the helper seat in the pic was designed to bear against the main spring seat and I can't see any problem with that. I'm guessing that the manufacturer uses the depth of the inner section of the helper seat to dictate the required characteristics (ie. amount of resistance from the helper & ride height).

[Mr2Mike]

Don't wish a granny egg sucking moment, but are you sure that the collar between main spring and helper is fitted the right way around?

[jimmystratos]

It's symmetrical. The area of the weight bearing parts as it is in the picture seems too small to last long. Can they be fitted without the adapter or will they move sideways.

Apparently the choice of putting the helper spring at the top or bottom depends on whether you want the weight on the sprung (top, good) or unsprung (bottom, bad)weight. This is also why progressive rate springs go on with the closer wound coils at the top.

[GreenV8S]

jimmystratos said:

Can they be fitted without the adapter or will they move sideways.

That sounds like a bad idea, there's nothing to keep the two springs aligned.

Worth talking to the suppliers to see what they make of the metal-on-metal situation, hopefully they'll tell you it's OK or have some idea how to avoid it.

[jimmystratos]

[quote]Worth talking to the suppliers to see what they make of the metal-on-metal situation, hopefully they'll tell you it's OK or have some idea how to avoid it.[/quote]

Demon Thieves said "why don't you fit a longer spring". Very helpful. Not.

[GreenV8S]

jimmystratos said:

Demon Thieves said ...

I think you probably need to go further up the food chain, you can't expect telesales guys to answer detailed technical questions.