Would 225lb springs on the front and 160lb springs on the rear would be ok for a locost. Its got a crossflow and type 9 box with sierra irs rear. Front has wide wishbones and rear shocks are almost vertical. Also is there any advantage to using helper springs?

Hi, I have 250lb on the front and 150lb on the rear. I have a live axle at the back.

I don't think I have helper springs but I don't know what they look like so can't be sure

I cant believe that there is only 1 person with springs on there car!

I will depend very much on your set-up and vehicle weight.

The leverage angles on your setup may vary a great deal from others depending on your shock absorber mounting points and wishbone length.

As a general rule 150 to 160 should not be too bad on a live axle.

I can't say on the front as my setup is different.

You normally run helpers to stop the spring rattling on full droop.

You suspension will have a designed ride height. Your coil overs will be designed to take a spring of an open length. If you go too stiff then there will not be enough weight to compress the spring to ride height. To obtain the ride height you could put a shorter spring on but it will then rattle on full droop.

So you run a helper. Eibach go one stage further and have a secondary spring with a reasonable spring rate. This gets complicated though.