I'm building a street/strip 66 Dart. I've converted the front end to coil overs and can either run 12" or 10" springs with the shocks I've got. Is there a reason to use one over the other? Which one is preferred - or does it even matter?

with the 12" spring you can use a lighter weight spring with the same ride height and get more store energy for better travel.

What kind of shock? What kind of installed shock and spring length are you looking at @ ride height?

Using the long shocks on the front usually results in WAY more front end travel than desired or needed and usually some type of limiter to be used in a fast race car.

Thanks. That makes sense. It'll be driven on the street, so I'll definitely have to make a compromise as far as spring rate. I'm leaning towards the 12" for the additional flexibility.



It's an adjustable coil over and I'll run them at about 13" ride height. Not sure on the spring ride height yet. That'll depend on the spring rate I end up going with. At that particular shock ride height, I can get away with either a 10 or 12 in spring.

The shocks won't be the limitation for front end travel - I have bumps stops for that. I'll be able to tailor how much travel the front end has by simply adjusting the bump stops. The car won't be what I'd call fast, and I already had the shocks, so I figured I'd try them for free.

I was always under the impression there is no downside to using the longest spring possible that will not coil bind as long as it gets the job done, or no reason to use a shorter spring if space for longer allows, we are assuming spring rate is chosen correctly for the application.

To answer the question, I would use a 12" spring. A light 12" spring compressed to fit in the same length area as a heavier 10" spring, that is not compressed nearly as much to hold the shock at ride height, will make the suspension more "lively" to help with pitch rotation. A decent adjustable shock and/or limiting the travel can be used to control it.

Thanks for the input. Looks like the 12" spring is the way to go.