Similar to the GX in the video, the gen3 4Runner stock droop is limited by the shock when installed, then next by the upper ball joint when the shock is removed. Extended length front coilovers require new upper control arms due to the increased length. With new upper control arms, the limit to droop will be the axles, just like the GX. The actual travel numbers are different, but the order of limitations is the same. This is all with stock arms, of course.

With 100% stock arms, I ended up with at 3/8" (actually, slightly over that - I think they were actually 11mm thick) top plate spacers to maximize the use stock arm travel (the lower arms get lifted just a bit to get the lower shock bolts in place).

By the numbers, on my 4Runner:
full extension (stock arms, pivot bolts loose): 25.25"
full compression (stock arms, pivot bolts loose, bump stops lifting truck): 16.75"
So, absolute max travel with stock arms/bump stops is 8.5"

I then set my front ride height at ~21.25" to give 4" compression travel and 4.5" droop travel, theoretically. I also went with the softest springs I had available to try and maximize front flex (V6 2WD springs) and verified the shocks don't bottom at full compression. It would be reasonable to go up another 1" if I wanted the look, before starting to lose too much droop.

I feel like I should check this on my ramps now...

-Charlie

Now we're getting somewhere...

I feel like an Excel spreadsheet with the right formulas could be used to generate a lot of this information plugging in things like shock compressed length versus extended length, spacers and custom arms

I too will perform the ramp test and do some math based on my suspension components specs

Sent from my Pixel 4 XL using Tapatalk

Coil spring rate is also going to be a big factor in how much you flex. A 500 lb/in spring will compress/extend further than a 600 lb/in spring by a theoretical 20% for the same given input.

Charlie, just to be sure we're on the same page, is this from shock eye CL to bottom of top hat?

No, hub center to fender lip, which allows you to measure with the wheel on or off. I was talking about wheel travel, not shock travel.

Haven't measured the motion ratio, but it should be around 2:1. Bilstein claims 4.61" of shock travel on the 5100's, which would generally confirm that (I had a little less than 1/2" of shock travel left at full bump with no spring when using nearly 8.5" of wheel travel). The OEM shocks are shorter than the 4600s/5100s, which is why those 3" spacer lifts kinda work.

-Charlie

Gotcha, thanks.

That’s a super cool video. Thank you for posting it. That guy explains everything perfect too.