RCA sizing

[kazi]

Can anyone tell me the general rule when it comes to selecting an RCA size? Are you looking for the same RCA height as the amount you have dropped the car? IE lowered car by 50mm so should have 50mm RCA?

Looking at getting a set made up and he currently shocks 50mm but I'm thinking that's quite a big size for an RCA seeing as most are 38mm?

[Project D]

It's a balance between amount of lowering, stiffness / shock travel and wheel clearance.

[totta Crolla]

Toyota did a good job of getting the roll centres right so the best way to approach this would be to measure the TCA angle without RCA and at standard ride height then aim to get the same TCA angle once lowered with RCA fitted.
The steeper the TCA angle is the higher the roll centre will be and the stiffer the suspension will be in roll.

[kazi]

thanks for the feed back guys. will give it a measure and see