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Thread: P11 Auto-X Setup help

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Posts: 191-200 of 220
2017-05-24 13:16:18
#191
Also I would like to know if your running into any axle stretching issues. I'm on Spec V 6 speed axles and they are already a tad bit on the shorter side. Moving the LCA out for me might pop them out haha.
2017-06-06 15:51:01
#192
Originally Posted by Vadim
Also I would like to know if your running into any axle stretching issues. I'm on Spec V 6 speed axles and they are already a tad bit on the shorter side. Moving the LCA out for me might pop them out haha.


Vadim, been busy with work and my house lately so not much has happened. I did extend the arms about 1\2" and that gave me around 1.8* negative camber. I was hoping for more but then again that is not measured on an alignment rack but a camber gauge on my driveway which is fairly level. No axle problems so far. Is the SAI angle same as scrub? again not sure what mine is did not make it to any alignment shop yet.

On another note, I am now looking a way to may the caster adjustable as well, obviously changing the length of the arms without moving the rear busing affects caster in a bad way, would be nice to get some back as I am trying not to run above 2* camber for braking and acceleration.
2017-06-06 16:27:25
#193
I feel that it would be better if I re-drilled the UCA mounting holes like you did to increase the angle and gain some camber there rather than using the LCA to gain neg. camber. My funds are depleted with the new tires coming in so its going to be "free" mods for the rest of the year for me lol.
2017-06-06 17:58:00
#194
Originally Posted by cayman_primera
Vadim, been busy with work and my house lately so not much has happened. I did extend the arms about 1\2" and that gave me around 1.8* negative camber. I was hoping for more but then again that is not measured on an alignment rack but a camber gauge on my driveway which is fairly level. No axle problems so far. Is the SAI angle same as scrub? again not sure what mine is did not make it to any alignment shop yet.

On another note, I am now looking a way to may the caster adjustable as well, obviously changing the length of the arms without moving the rear busing affects caster in a bad way, would be nice to get some back as I am trying not to run above 2* camber for braking and acceleration.


Do you mean extending the control arms got you -1.8* total, or in addition to what you already had?

SAI determines the scrub radius yeah, but SAI also causes you to lose negative camber as you turn the wheel. I'm at 17* with -0.7* camber on stock UCA's, with shorter UCA's it might be even worse...

See my comment below for more caster....

Originally Posted by cayman_primera
I feel that it would be better if I re-drilled the UCA mounting holes like you did to increase the angle and gain some camber there rather than using the LCA to gain neg. camber. My funds are depleted with the new tires coming in so its going to be "free" mods for the rest of the year for me lol.


Agreed to that, I like free little mods here and there. The UCA lower mounting point on stock arms is as good as shorter upper arms! Now lower UCA mounting point + shorter control arms = WOW!

I have another UCA mod that I've been quietly working on, I wanted to do camber curve testing before I mentioned it, but figured would post it, since you want more caster. If you look closely enough at the center hole in the bracket, you will see a sharpie mark of where the bracket was before.



The premise of this mod is, by slotting the holes towards the front of the car it will move the bracket towards the back of the car increasing your caster. By slotting the holes up, it will lower the bracket and raise the roll center even more. Thus as a compromise between the two I slotted them diagonally, when I put the car on the alignment rack it had 4.5* of caster, 1" lower then stock, stock UCA, SuperPro Offset rear bushings, and these two UCA bracket mods.

Years ago the car had 3* of caster, before SuperPro offset rear bushings (+0.50*), stock UCA's and stock mounting points.
Last edited by Vadim on 2017-06-06 at 18-17-48.
2017-06-06 20:20:14
#195
Originally Posted by Vadim
Do you mean extending the control arms got you -1.8* total, or in addition to what you already had?


Total, before it was at -1, now it is at -1.8. I expected more but remember that it is also changing the caster so although it is 1/2" longer it moves backwards a bit as well.

The premise of this mod is, by slotting the holes towards the front of the car it will move the bracket towards the back of the car increasing your caster. By slotting the holes up, it will lower the bracket and raise the roll center even more. Thus as a compromise between the two I slotted them diagonally, when I put the car on the alignment rack it had 4.5* of caster, 1" lower then stock, stock UCA, SuperPro Offset rear bushings, and these two UCA bracket mods.


I was actually thinking of doing something similar as I actually drilled in the wrong spot on my first attempt and the UCA did not fit but not offset like you have. Did you use the lower mounting points plus offsetting the bracket?

Going to be doing this no doubt! Off topic but could you check out the tuning maps thread, I posted my timing map there and want some advice. really new to engine tuning since I was more concentrated on suspension but now that suspension is getting really close to ideal its time to spend more time on the motor and fine tune it.
2017-06-06 20:29:07
#196
Oh weird, I thought you were at -3* of camber before? Did you raise the car up, or install stock length UCA's?

I did both, I love the lowered uca mounts (plus moves it back slightly), it helps tremendously. The only issue is I can't use those mount points with SuperPro bushings at full negative camber, but fits fine with stock or Cusco's. I want to shorten my arms more, but I'm not sure I want to modify the cusco's....

About timing map: Sure will do.
2017-06-06 21:08:39
#197
Originally Posted by Vadim
Oh weird, I thought you were at -3* of camber before? Did you raise the car up, or install stock length UCA's?


You are correct, I was at-3* with shortened UCA which the bushings were failing, I fixed another stock set I had with new bronze bushings and replaced me shortened set. so yes I am back at stock length arms. I felt that -3* was a bit too much and now there is less roll I think that was the right move. Maybe a a shorter arm of 8mm or 10mm would be better.
2017-06-07 00:16:33
#198
Now you got me curious, how much shorter were your custom arms? Also do you know how much lower then stock you are? With stock UCA's and stock mounting points I gained -0.5* being 1" lower, and gained another -0.2* by lowering the mount points of the UCA.

My goal is -2* of camber, 4-5* of caster, and a more aggressive camber curve. My hopes is that my new AD08r's in 235/45/17 (as wide as most 245 tires) might be less sensitive to our camber challenged cars.
2017-06-07 13:04:51
#199
Originally Posted by Vadim
Now you got me curious, how much shorter were your custom arms? Also do you know how much lower then stock you are?


Shorten arms were 13mm shorter when I did final measurements, I am not sure how much lower I am than stock but has to be around 2.5".

235/45, that is a tall tire. I guess at your height it shouldn't be a problem. -2* is the better setup for turbo power, if I was non turbo I would consider a bit more but I don't see my tires rolling on the sidewall.

I am going to be re-drilling the mounting bracket this weekend and see what the camber is then as well.
Last edited by cayman_primera on 2017-06-07 at 13-18-03.
2017-06-07 13:28:46
#200
Gonna run through some math here quickly...

If 10mm shorter arms = -1* of camber (which they are confirmed on my car). 13mm shorter would give you approx -1.3* then.

Stock camber curve gives you -0.5* for 1" of compression (lowering the car). From my camber curve measurements, another 1.5" compression should gain you another -0.7*, or -1.2* total at 2.5" drop.

Couple that with your 13mm shorter arms = -2.5*, unless going shorter then 10mm made a more aggressive camber static gain (possible, since our UCA travels in a 3 dimensional plane unlike typical SLA suspension).

So back to your -1.2* at 2.5" drop, if your at -1.8* right now, that means 12mm longer LCA got you -0.6* of camber. Definitely a slower camber gain then with UCA's.

I'm basically wanting to do offset bushings for the front LCA to lengthen it a little, to get me to -2* with a possibly raised car (new tires are a bit taller then expected).

Also just an FYI, my LCA is 360mm from LCA mount center line to ball joint.
Last edited by Vadim on 2017-06-07 at 13-38-45.
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