“Stiffer” is extremely misleading. Because the icon and deavers both have more leaves than stock, they are more compliant and more progressive. Off-road, they have the net effect of actually feeling SOFTER over big bumps because they let the shock do what it’s supposed to. With my stock springs I had stuff flying out of the bed when hitting speed bumps fast, and now with the icons my tools in the bed barely even make noise.
Yes, raising your coilovers increases spring preload and will therefore make your front end feel stiffer. However, there are many other effects to consider. By raising preload you are also adjusting your steering geometry at ride height and your tie rods will now exert a different angle of leverage on your spindle, making your truck handle differently. Your tire will now be able to exert more leverage on your steering rack, increasing bump steer and wandering. Whether you feel it will handle better or worse is subjective. You also need to consider the calving of your front shock when adjusting preload. All of the aftermarket coilover options have much longer shocks than stock, and are valved to perform differently than stock at the same height. I raised my King coilovers to about an inch and a half over stock (at the tire, not at the spring), and it rode much better, absorbing bumps more smoothly because I gained all that up travel.
You also need to consider the fact that your aftermarket coilovers may not have the same spring rate as stock. I’m not sure about fox, but I know for a fact that King and Icon coilovers both have at least 600 lb. springs. Stock is 550.
Another factor playing into front end comfort is the way the dial adjusters work. They’re inherently flawed which is why a custom valving setup or a secondary bypass can be so effective. Whereas an external bypass shock uses tubes placed at specific points on the body to route additional shock oil flow around the piston and adjust compression and rebound that way, when you spin your compression adjuster on your coilover you are actually threading a pin with a hole cut into it, in and out of an assembly, and all you’re doing is restricting shock oil flow to a greater or lesser degree by adjusting how much of the pin is exposed. Your adjuster is simply adjusting the oil resistance the piston encounters, as opposed to an external bypass shock that only adds or subtracts oil (yes the IBP shocks do have internal bypass channels, but you are still adjusting oil flow with the adjuster just like you would in a normal non-IBP shock.
