yes, if i install the spacers on top (i have a ct9a) then that promotes "anti lift" but will also reduce dive as well, correct?

 

yeah i have gerrard spec stuff also. i like it, but a) its outdated i feel and b) my driving style/skill didnt 100% match it, so i made some tiny tweaks.

 

My main point was to explain why I have those settings, not that I chose them or came up with them on my own. I haven't done any tweaks based on driving style, but I can say that up until my last two events, I did not have all this tail wag. I'm not sure if that's because the car was faster than it ever was before those last 2 events or what.

 

^ did you add the front AP brake kit within those two events?

 

I added the AP kit just before this last event at NJMP. The previous event had my normal brakes that I had used for a few years, which was pretty simple: SS lines, slotted rotors, stock Brembos, Motul fluid, and Hawk HP+ pads. I had never experienced this crazy light rear under hard braking until that previous event (High Plains Raceway in Denver, CO). It's possible that the tracks I had been on previously didn't have a very hard braking zone at the end of a 100+mph straight.

 

i installed mine with the spacer at the bottom. i would think that you want zero anti-lift (pro-dive). spacer on top if you want added anti-lift (pro-dive).

 

does AP kit provide more brake torque than oem setup? i know AP rotor diameter is close to oem rotors, but pad surface area, piston surface area and pad friction is different.

 

Geometry does not care about chassis code. In either case, if the thicker washer is on top, you get less anti-lift and anti-dive, which I wrote as pro-dive.

Note, also, that anti-lift / anti-dive is highly dynamic. As the tail rises under hard braking, you get more anti-dive in the front and more anti-lift in the rear, albeit a little too late.

Also, also, this is why, when you see a rough spot ahead, you don't lift (off the gas). Pro-dive geometry adds compliance to the suspension. By staying on the gas, you angle the front lower LCA upwards (in the front), which is pro-dive, which adds compliance. Yes, part of the smoother and more control ride across the rough spot comes from less weight on the front wheels, but the rest comes from the change in front geometry.

 

Yes, anti-lift and anti-dive require the same geometry, but that geometry is a lower LCA that is tilted down to the front, so you put the thinner spacer above the arm in the rear.

 

Great thread! I have been road racing the S1000RR the last two years and have taken a break from the evo....until yesterday where I joined the local Healy club at Blackhawk Farms. Caught the bug again.

To help myself better understand and for others as well......

We have two conflicting opinions regarding the light rear end under heavy braking

1. Too much front bias
2. Not enough front bias

Guys that adhere to #1 are switching to a more aggressive pads in the rear which effectively takes away some front bias and they are reporting less dive. If I understand the contrary opinion provided by Iowa, he is saying that you can do that as a way to get the car to be more stable, but that the reported minimize in dive and stability is because the car is experiencing less total braking.

Now assuming I have the above correct, it seems to me that (given the limitations of the suspension geometry and assuming that remains constant) this issue is as simple as the laws of motion in that the more braking you are doing, the more weight will be going to the front.

Now you might say, well I have four tires and I'd like to use them all the brake so that I can brake the fastest, but (again assuming the suspension doesn't change) the more braking G's you create, the more weight transfers forward. At a static moment of 1g of deceleration, there will be a certain amount of weight on the front tires and much less on the rear tires. If the rear tires are locking up and the fronts still have traction at this weight distribution, it seems to me you'd want to add more front bias.

Though it is an apples to oranges comparison, think about MotoGP guys coming in to a corner after a long straight. Rear wheels aren't even touching the ground.

EDIT: None of the above would SOLVE the light rear end issue it merely addresses the brake bias for maximum braking. Clearly, there are limitations in the suspension geometry, some of which can be addressed to help the squirley rear end which would probably be the best place to start, then once that is done, tune the aero as necessary?

 

Great....my instructions said to put the small spacer on the top LOL. Now I gotta go switch it?

 

From what I've been reading it depends on your spring rates.

https://www.evolutionm.net/forums/ve...rs-review.html
https://www.evolutionm.net/forums/ev...questions.html
https://www.evolutionm.net/forums/ev...t-yea-nay.html

I'm leaving mine where it is, I need the front end to be compliant while braking.

 

I read all those and still don't know what the spacer on top accomplishes. It's either anti-lift, anti-anti-lift, pro-lift. ...or pro-anti lift. To Hell if I know LOL. I'll just put it on the bottom and run the" stock" setting.
I'm guessing spacer on top reduces the amount of factory anti-dive (essentially let's car dive a bit) to be more compliant with stiffer spring rates. On bottom is probably better for people like me that have softer rates, off which I have 8k.
Am I close?

 

Some additional info:

 

Dear Lord thank you. Finally something that makes sense! Gracias, dude. So my setting is where I want it.
So this kit is actually an anti-anti-lift/ dive kit. It's not named for what it DOES so much as what it affects.