Modify Stock LCA ? Tell me why I cant.
03-12-2009, 10:54 AM
#42
On GM A-bodies, the factory boxed the control arms because the rear sway bar bolted to them. Cars without rear sway bars got unboxed control arms. The logic for boxing them in that case is obvious.
The point of the argument in the suspension FAQ is that the rubber bushings absorb all of the twisting forces. The use of hard poly bushings defeats this, so that the twisting force is transferred to the LCA itself. In the case of rubber bushings, the twisting force is not applied to the shaft of the LCA, thus rendering boxing unnecessary.
The point of the argument in the suspension FAQ is that the rubber bushings absorb all of the twisting forces. The use of hard poly bushings defeats this, so that the twisting force is transferred to the LCA itself. In the case of rubber bushings, the twisting force is not applied to the shaft of the LCA, thus rendering boxing unnecessary.
Last edited by RevGTO; 03-13-2009 at 12:40 AM.
03-12-2009, 11:09 AM
#43
If thats the case then you're saying that every single aftermarket poly/poly lca ever sold was a waste of the buyers money?
03-12-2009, 02:17 PM
#45
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Alright, it's time to understand that the flex in the LCA's is just a not issue. The bushings is where the problem is. The stock "star" style bushings allow for too much movement at the mounting points. To reduce this all you need to do is to replace the bushings with Moog solid rubber bushings. This reatains the NEEDED articulation for cornering while decreasing deflection. The arms only direction of weakness is a twisting load, however this just does not cause any problems since the arms are so short to begin with. The PHB on the other hand does have a bit to be gained by bracing it since it is much longer. The rotational force of the rear end pushing up on the car is all taken care of by the torque arm on our cars (unlike the SN95 mustangs) so there isn't nearly as much load on our LCA's. Hence yes you wasted your time welding the LCA's but not on the PHB. To fix the issues in the LCA's simply get moog replacement bushings.
03-12-2009, 08:31 PM
#48
In my opinion, after driving rod-end, poly end and 1LE (moog replacement) rubber bushings, the 1LE rubber has about 95% of the rod end capability without the noise. I went back after trying all the other combinations out there. For the type of driving I do which is mainly autox.
03-12-2009, 09:35 PM
#49
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I wouldn't say better bottom line. I would say better for drag racing or for people who want to use their LCA linkage to assist in roll resistance. I prefer that my swaybars and springs handle that job in my situation.
03-13-2009, 12:32 AM
#50
I have 1LE bushings in stock LCA's on my M6 car. I thought about boxing them, but after studying the matter, I couldn't come up with a convincing reason to bother with it.
Probably, in that less money could have been spent on 1LE bushings for a better overall result. That being said, I have poly/poly LCA's on my A4 car, because they were on it when I bought it. I haven't found them to be a problem after five years of DD and track use. I get some wheelhop during a burnout, but given the limitations of my setup, I think they do pretty well. I may switch to 1LE bushings on stock arms on this car just to experience the difference - if it is perceptible.
03-13-2009, 12:42 PM
#53
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Yes I would purchase them reguardless. The moog bushings have much less deflection which will help with your launches. They also don't bind in the turns like poly which basically makes the car act as though the rear sway bar is larger (more oversteer). The stock bushings are a weak point on the F-body (unless you have a 1LE car) so it's one of the first mods I recommend. It's cheap effective and reliable. Other stock parts I suggest not going aftermarket for are the upper and lower A-arms. The stock upper A-arms actually weigh less than aftermarkets (or about the same) and the stock lowers are just stronger than the aftermarket offerings.
