Why isn’t it possible (practically speaking) to move the front wheels forward w offset control arms?

Just curious…

Instead of a CMC, why not move the front wheels forward with different control arm geometry?

 

To some extent that’s what is being done with some new non Toyota UCA’s. However, there is only so much room.

 

Your wheel movement comes from the LCA. JD Fab makes something that moves the LCA mounts. But there is only so much you can do with IFS

 

There are many measurements that go into a front suspension. For example scrub radius. Start moving things around and you will get way out of wack.

 

Offset lower balljoint...

 

The tie rods and axles prefer to only have to articulate up and down, not diagonally. So finite adjustments are necessary.

The upper can move the spindles and rotate it, but a full lower arm movement is detrimental to geometry.

 

You can do this but it's limited based on how much you want to redo. This is what the RCLT kit from Marlin Crawler does. Here's doing it on 2nd gens: https://www.tacomaworld.com/threads/how-to-fit-bigger-rubber-my-way.742142/


The biggest issue you run into if you just want to remake control arms are tie rods and cv axles. Eventually you get to a point where the kinematics or clearance with these won't work without bigger modifications.

 

A set of lower control arms is currently in development for this exact thing.

https://www.tacomaworld.com/threads/game-changing-lcas-btffabrication.766413/

But you have to take into account a whole host of other issues. For one this closes the gap between shock lower and cv axle. Plus there is far from unlimited forward clearance when you start pushing the wheel forward. Once you go past center like in the fender you are loosing up travel clearance with every cm you go forward.