Suspension and Chassis Questions about your suspension? Need chassis advice?

Make Sure I Do this Right the First Time

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Old 02-17-2011, 10:30 AM
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Make Sure I Do this Right the First Time

Ok so I have Koni yellow shocks and struts and BFG g-force super sport a/s tires (245 50 ZR16) on order. I'm having these installed with my Eibach pro-kit by a local shop soon. I know that when I lower the car, even only this 1 inch, that I will need to get an adjustable panhard bar. I was going to order the UMI double adjustable panhard bar and now I need to decide on if i will get LCARBs and adjustable LCAs. I know they will be necessary to keep my instant center after I lower the car, but do they need to be adjustable? I also remember reading something about the LCARBs and LCAs affecting cornering and this car will be used for auto-x so I care more about handling than launch. Thanks in advance for the time, I'd like to not have to change things again in the near future.

~Matt
Old 02-17-2011, 11:21 AM
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Re: Make Sure I Do this Right the First Time

adjustable everything is nice, but between the LCARBs and an adjustable PHB, you should get to where you want to be. you could always grab a set of used non-adjustable LCAs and see how they feel - less money out and you can always recoup it if you decide you want to step up to something more tweakable
Old 02-17-2011, 12:15 PM
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Re: Make Sure I Do this Right the First Time

Get adjustable, or you will end up buying a 2nd set of adjustable PHB and LCA like i did! But don't get rod ended if you are driving the car for the street, get del alum.. Also poly isn't too good back there because it causes binding. The adjustable PHB will help put the rear end back in the center (which is needed when lowering). The adjustable LCA I don't think is that important but all I see it doing is changing the location of the diff fowards or backwards, The LCARB is important because that will enable you to keep the angle of the control arm parallel to the floor or lower (on the axle side) because when you lower the car the body side mounting point ends up being lower (depends on how low you go) and that will create major traction problems.
Old 02-17-2011, 12:42 PM
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Re: Make Sure I Do this Right the First Time

I did the Eibach Pro-Kit (like you), and all I did was an adjustable panhrdd rod (the cheaper Edelbrock rod) to recenter the rear axle and I have no issues at all 3+ years going. The only purpose I see in the lower control arms and relocations is for racing - when you need to be sure that the pinion angle remains in tact with huge hp take-offs. Stronger controls arms yes might be nice/beneficial for street, but relocation I don't see as necessary with a simple 1" drop on a street driven car with little hp mods.

But I'm no suspension expert - all I know is that my car rides excellent for me on the street, and handles great.
Old 02-17-2011, 01:54 PM
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Re: Make Sure I Do this Right the First Time

At 1 inch rear drop? do not bother with relocation brackets (LCARB's). Get adjustable LCA's, you will probably need them if not now then in the future for changes and modifications as well as slight manufacturing tolerance defects in alignment- just a great tool to have and worth the extra expense for most everyone in the long run of owning and modifying a 3rd gen.

Just a little correction note: in your opening paragraph you list the term "Instant center" and refer to keeping the rear end centered under the wheel wells- just a friendly correctino, that is not "instant center". Instant center is a strong termed used in referencing chassis roll. You mere want to use the term "center the rearend".

Dean
Old 02-17-2011, 01:57 PM
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Re: Make Sure I Do this Right the First Time

Also, I want to add an important opinion on parts purchase. Prior to buying LCA's I would greatly suggest you forst spend the money on solid bearing strut mounts so they can be installed with the new struts and alignment- money much better spent for performance value.
Old 02-17-2011, 02:24 PM
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Re: Make Sure I Do this Right the First Time

Ah! I remember now! The alignment tech was able to correct the thrust angle of the car by adjusting the LCA's, i'm not sure how that changed driveability but I assume that it just propels the car in a more straighter direction when accelerating.
Old 02-17-2011, 04:14 PM
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Re: Make Sure I Do this Right the First Time

Originally Posted by hellz_wings
Ah! I remember now! The alignment tech was able to correct the thrust angle of the car by adjusting the LCA's, i'm not sure how that changed driveability but I assume that it just propels the car in a more straighter direction when accelerating.
For the most part- Yes. The only remainng factor is that of which was not mentioned whuch is where the cg of vehicle weight is positioned in front of the rear wheels as they push it. This changes with drivers weight as well as passenger weights, positions, baggage, fuel, rearend carrier, tire pressures, and fuel load- Not accounting for any road conditions pertaining to grip. Then there are also slight factors pertaining to Shock damper values and how the tires load weight upon weight transfer, as well a bushing materials flex, spring rate constants and chassis flex... but now I am being **** about a basic answer in normal street driving. Point is that with a perfect alignment, even 10 very very slight problems can all end up adding up to something still not feeling right even when the #'s show correct in a perfect world. This is what happens slightly more as a chassis and componants age.
Old 02-18-2011, 06:46 AM
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Re: Make Sure I Do this Right the First Time

Thanks for the input guys this is what I needed. Sorry I used the wrong term vetruck, you explained what I meant. I was planning on getting spohn strut mounts very soon and I know it makes sense to change them with the struts, I just figured I needed the lcas and/or lcarbs bc of the springs. All poly brushings are in the near future too.

I remembered reading that lcas were more for traction and launch but do they hurt cornering? Are del alum ends definitely the way to go for the double adj panhard bar? I have to order this stuff soon. Thanks again.
Old 02-18-2011, 07:49 AM
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Re: Make Sure I Do this Right the First Time

Ok I need your opinions:

adjustable del sphere panhard bar

adjustable del sphere lcas

progressive bump stops (necessary?)

spherical upper strut mounts

Is there anything else I need to install these parts and the shocks/struts/springs? Like maybe spring seats? I'd like to order everything by this weekend so the shop can do it all at once. Thanks.
Old 02-18-2011, 02:14 PM
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Re: Make Sure I Do this Right the First Time

I got the poly/del sphere combo PHB and LCA. I don't know know if ALL dep-sphere is better, I imagine it is but that's just a guess. What I can tell you, is that this was a huge step up in terms of handling AND straight line traction over the all poly PHB and LCA. The back end is just MUCH more predictable like this. Pair that with a good set of tires, shocks and springs and you're golden!

I got J+M strut mounts and they work perfectly well enough to get the front wheels aligned to whatever you need them to be at.

I ordered poly bump stops for the rear just for the hell of it but my old one was NOT worn out so that was a bit of a waste of money cuz it's over 100$. :\

Front control arm bushings also help a bit for handling (over the stock rubber bushings). I went poly for this.
Old 02-19-2011, 06:35 AM
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Re: Make Sure I Do this Right the First Time

I'm thinking I will go with spherical rod ends because I'm choosing to go for the performance end and I don't care if they squeak.
Old 02-20-2011, 12:17 PM
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Re: Make Sure I Do this Right the First Time

I ordered Spohn spherical strut mounts and the UMI double adjustable, mild steel panhard bar. I don't have unlimited funds so I got what i could now. Best bang for the buck I hope. In the future I'll get adj lcas, lcarbs and the rest of the suspension done.

~Matt
Old 02-20-2011, 12:31 PM
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Re: Make Sure I Do this Right the First Time

Originally Posted by 88WS-6
I ordered Spohn spherical strut mounts and the UMI double adjustable, mild steel panhard bar. I don't have unlimited funds so I got what i could now. Best bang for the buck I hope. In the future I'll get adj lcas, lcarbs and the rest of the suspension done.

~Matt
sounds like a good start
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