k maybe someone in here can help me. what is the difference between the S1 and the L1 for the j's racing front rca?

 

for the front RCA, there are L1, L2, S1, S2

S1 and S2 are for lowering 0~40mm

L1 and L2 are for lowering more than 40mm

S2/L2 will give you more camber than S1/L1

they use to design 2 thickness, now they change to 2 pieces so you can take the extra piece off and make L into S

 

S1/L1 = 2-5 degrees camber
S2/L2 = 3-6 degrees camber

This piece is a 2 parter...
Do you need / want to add more than 2 degrees of camber or are you looking for the RCA function plus the camber correction?

The original concept was that when the car has been lowered more than 40mm the roll center needed to be adjusted, using the L2 camber joint effectively spaced the lower arm down so that the geometry of the suspension was returned to a more neutral position where Honda's engineers designed it to be most effective.

If your car has not been lowered more than 40mm then the roll center of the suspension geometry does not need to be corrected.

I believe you can still order the S1 or S2 which will only allow you to dial in more camber, no RCA correction (slightly cheaper but not worth it IMO). If you order the L1 or L2 the spacer is supplied which can be installed for roll center correction or it can be left off if its not needed. Lots of options here

 

when the car is lower maybe 20mm, even stock can get more than 2 degrees, S1/L1 adds no more than 1 degree on top of that

i think S1/S2 still "changes" some roll center (i don't use the word "correct" anymore cos now i donno which one is the "correct" setup for different setups)

wat J's says about RCA is it raises the roll center back up closer to the center gravity, the closer the CG and RC is, the less body roll the car will have on the same spring rate

i forgot if J's mentions about the geometry, but i believe the car will have closer geometry to stock, on the other words i think the camber, caster changes during body roll is closer to what a stock S behaves

however tho, there is no easy way to calculate the "new geometry" and then dial in the ride height/spring rate into a good balance, it will take a driver to drive good and knows a good amount of true feedback to tune it right

sometimes when you have really stiff spring rate, street tire grip, stiffer sway bars, maybe you won't need that much carmber or camber gain anymore

 

Ikeya Formula has a write up on their site click here and scroll down. It has some diagrams to help you visualize whats happening to the cars suspension when the CG has been lowered and how it effects RC.

 

this is the EXACT answer i was looking for! thank you so much!

i get the difference between s1/l1 vs s2/l2, i just didn't get the difference between the S and L. now i do thank you so much!