The 100 likes to have the diff spaced down in the front for 50mm lift or more, and started doing these back in 2002, as well as fixing the front A arms which have a habit of cracking, and just adding the ARB bracket doesnt fix it, it just stops it dropping to the bump stop when it does.
The standard car runs from 16"rim to fender 720mm, [add 12mm for each rim size up from there, ] once lifted with something like our Bilstein Platinum kit we can go to 775mm and keep the minimum amount of droop required for the front to stay reliable, and the cv boots and cv's to have a normal service life. Just "winding up"the torsion bars doesnt change the spring rate, only the ride height, like fitting coil spacers, and if you adust them, clean the threeads, anti sieze them, and never adjust them while loaded, always jack the car first. If they catch in the thread they are $108 and afew days from Toyota, and you have to cut them out with oxy, or plasma. We get many that have had the threads stretched and wont come undone, and never been lubed or anti siezed.
With Fox Long Travel shocks, the front can go to 795mm, with the longer shock, and keep the minimum amount of droop required, and stop the cv's being in any pain.
We also change the steering rqck bushes to help with torque steer, and chnage the inner lower bushes to stop toe pull with bigger tyres, and we also now do new top arms which have firmer bushes to aid toe pull with bigger tyres, and give us standard wheel alignment settings back at the 50mm + lift in the front.
Been fitting many out with 35"tyres lately too.
The average 100 IFS we kit out is somewhere between 3.7 and 4.2 tonne fully loaded all aboard, and they travel all over the country, remote as you can imagine, where reliability is super important, if you dont know how to fix it, some customers over 400,000km from thier 100's now, and as much as we fix many, especially that have been to NSW shops and had issues, when srt up correctly, they are a great truck. We also do our own wheel alignment spec too, to help with LHF tyre edge wear.
Currently the most popular truck we see for these mods, 3-4 a week, closely followed by new Prado's, Patrols, not so many 200's.
We have done suspension lift, coils and T bars on many AHC Saharas as well lately, by adjusting the shock and lift pressures in the system to stop it dropping to low setting, and add 40mm of lift with heavier rate coils and T bars, and this adjusts the shock valving for improved ride at the same time.
But get it wrong, Toyota only has one machine to calibrate the hydraulics, and they charge over $500 just to freight it in and connect it