boricua_s13

anyone that has knowledge doing ca18det swap ill pay you to finish it and make start. hard part is done with dropping engine just i believe messed up on the wiring part. hmu at pm box. neep help asap

MookHaasa

Wiring shouldn't be to bad on a CA. What have you done thus far in the swap wiring wise?

boricua_s13

wiring is done if done correctly dont know, fuel pump wont kick on neither.

92s13

the start of my FLCAs

Chris28

You definitely get bump steer when they aren't spaced the same amount, but since they are travelling down different paths the farther you get away from the stock location the more ackerman you get too. Good call on the GKTechs, if I didn't already have PBM knuckles I'd seriously be considering ordering a set. As for the rear, you're right you'd get some weird toe changes during compression. The PBM, Driftworks, and soon to be released GKTech rear knuckles all move everything down the same amount so I've never even thought about how the rear geometry reacts to spacing down different arms.

Chris, that LCA looks awesome! Do you know what ball joint RB is using? I assume your knuckles are going to get drilled out to accept the new taper?

MookHaasa

Does it have spark? Does the starter turn over?

Hijacker

That's not how Ackerman works, though. Ackerman is calculated by the angle of the steering arms in relation to each other. If you draw a line through each arm, their lines should intersect near the rear axle for optimal performance. Spacing the balljoint doesn't move the knuckle, so it doesn't change the lines drawn through the steering arms. The only way you can truly change Ackerman is to physically move the arms like the modular arms on the GKtech knuckles. Zero Ackerman means they're pointed parallel to the front-rear line of the car, and reverse Ackerman is when the lines intersect in front of the car at about the same distance from the front axle that the rear axle lies. You can amplify the effect by dialing in static toe out, so I could see if spacing the balljoint forced the knuckle out further delivered a changed Ackerman effect, but given the angle of the front strut and knuckle, the control arm should just swing back down in its standard arc, not moving the knuckle.

Chris28

Wouldn't you measure from where the tie rod pivots from though? If you space down the knuckle ball joint and tie rod ball joint then draw a line through their pivot points it would be a much more severe angle and would intersect before the rear axle. Not arguing, just asking/wondering for the sake of learning haha.

Hijacker

If you're only spacing the control arm, the tie rod pivot doesn't change so Ackerman would stay untouched. Even if you space the tie rod pivot, it won't displace over the arc like the control arm will since you can change the length of the tie rod to accommodate. Since the pivot would stay within a few milimeters of it's original plane, ackerman shouldn't be affected much if at all. If the tie rod end mated to the knuckle at an angle, i would agree spacing it would change ackerman a lot, but it's pretty sqaure to the horizontal plane. The main benefit of spacing it is so the tie rod's arc of movement can equal the control arm's. On most production cars, eliminating bunp steer entirely is pretty difficult, but I think controlling it as much as possible is the best bet.

Chris28

The oem tie rod mounts to the knuckle at about 10° from perpendicular to the ground. This entire thread is awesome, but he modded his knuckles on the last page so that he can adjust bumpsteer without afffecting ackerman:

http://nissanroadracing.com/showthre...t=2703&page=81

This thread also gets pretty interesting in the last few pages:

http://nissanroadracing.com/showthread.php?t=3750