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Ride height: Positive Rake vs. Negative Rake

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Old Jan 3, 2008, 08:10 PM
  #91  
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It's too late to tackle that here (its 10pm in Chicago). But I can tell you this: I will take the concept of a roll center over that FAP concept any day of the week and twice on Sundays. Why? I don't feel like calculating tire loads, and the RC gives me an approximate but IMO accurate enough idea of how the front will behave under specific circumstances. Maybe it's not accurate enough to get precise jacking forces, but when you're at the level where you're calculating tire loads, you most likely have a nice suspension simulator that you can simply plug numbers into and get numbers out.

Or... maybe I am missing something very important. In fact, I know I am. That thing is sleep.
Old Jan 4, 2008, 11:36 AM
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Cliff notes.... Don't slam your car.

If you have slammed the car then you probably don't track the F'ing thing anyway.
Old Jan 4, 2008, 11:38 AM
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Hey mine's lowered--and I autocross it!

My ride height is only lowered about an inch though...what constitutes being slammed?
Old Jan 4, 2008, 07:00 PM
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If your front lower control arms point up and out from the center of the car then its too low. Shouldn't be lowered any more than parallel to the ground. At least that is a rule of thumb.
Old Jan 4, 2008, 07:40 PM
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actually you shouldn't even lower it until your parallel. once you're at parallel then any compression gives you positive camber or negative camber loss.
Old Jan 7, 2008, 09:26 PM
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So what if I get SWIFT MR SPEC R springs for my Stock Bilsteins? Would I have to increase the front track (use spacers 10mm KICS spacers for the stock BBS rims) as well as increase the negative camber (-2.5 on stock camber bolts with another -2 deg from camber plates) to get less understeer during inital turn-in?
Old Jan 7, 2008, 10:07 PM
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Originally Posted by trinydex
actually you shouldn't even lower it until your parallel. once you're at parallel then any compression gives you positive camber or negative camber loss.
And with the roll center correction kit? What happens then (assuming we're still talking about a car where the lower arms are parallel or slightly pointed upwards from the center).
Old Jan 8, 2008, 08:02 AM
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Originally Posted by timmiii
So what if I get SWIFT MR SPEC R springs for my Stock Bilsteins? Would I have to increase the front track (use spacers 10mm KICS spacers for the stock BBS rims) as well as increase the negative camber (-2.5 on stock camber bolts with another -2 deg from camber plates) to get less understeer during inital turn-in?
FYI most camber plates are going to end up raising the front a big more than normal. I really don't suggest going with plates alone. If you are that hard core I would go straight to coilovers.

I'm not sure what kind of racing you do but if you stick with the swifts then adding a rear sway bar will help reduce understeer and help keep the car flatter. Many people will argue about the RSB but even Whiteline will tell you its a performance enhancing mod.

Originally Posted by Vankuen
And with the roll center correction kit? What happens then (assuming we're still talking about a car where the lower arms are parallel or slightly pointed upwards from the center).
The RCC kit will help but if you've lowered the car to the point of inverted LCAs then you are lower than optimal for BEST handling. This doesn't mean the car will handle like crap. Up until last year next to no EVOs were using RCC kits and they still had performed wonderfully.
Old Jan 8, 2008, 08:23 AM
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Originally Posted by timmiii
So what if I get SWIFT MR SPEC R springs for my Stock Bilsteins? Would I have to increase the front track (use spacers 10mm KICS spacers for the stock BBS rims) as well as increase the negative camber (-2.5 on stock camber bolts with another -2 deg from camber plates) to get less understeer during inital turn-in?
I wouldn't worry about increasing the track....but I would max out your camber plates and run less camber from the bolts. This helps improve your roll center.

An adjustable rear sway bar would help as well.


- Andrew
Old Jan 8, 2008, 09:52 PM
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I was thinking about setting my camber to -1 deg from the bolts and setting the camber plates to -1.5 to get -2.5 deg of camber in total. For some reason I can't get more than -1.7 deg of camber on my right front bilsten, I suspect it might have been bent slighty by a recent encounter with a really large pothole (obviously I couldn't avoid it).

Before I was able to get -2.5 deg of camber up front with stock camber bolts alone. I just hope it's ok for me to run springs, camber plates and a rear sway bar. I checked and re-checked and counldn't find anything wrong with the components on the right front side. I was really hoping to bring my car out to AutoX this spring but I guess minor setbacks like this won't allow me to do so, so i've just been driving my car on the street.

Last edited by timmiii; Jan 8, 2008 at 09:54 PM.
Old Jan 9, 2008, 06:36 AM
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I just had a thought, if I do get springs (swift MR spec R's) and camber plates (Cusco) then the springs give a 1.4" drop in front and the camber plates are 0.5" thick, then I'll only see a 0.9" drop in front. In the rear the springs drop it 0.8", so wouldn't I still end up with a negative rake. Wouldn't that be a bad thing?
Old Jan 9, 2008, 06:46 AM
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If it makes you feel any better, I went from using camber plates on my Zeals to the stock top hats on the KW's. I should still be able to exceed -2 camber.
Old Jan 9, 2008, 04:20 PM
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Help?
Old Jan 9, 2008, 08:50 PM
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I wouldn't worry about rake as much as alignment. An aggressive alignment and sticky tires will make any evo handle great. Most people do springs as an appearance mod. The truth is the stock suspension is very good and adding springs doesn't always make it better. Even coil overs need to be dialed in.
Old Jan 9, 2008, 09:07 PM
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So for my situation what should I do? Replace the stock strut or jsut set the camber to -1 deg at the bolts and get camber plates?


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