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Discussion Starter #1 (Edited)
So here's where I sit with the car...

Front urethane bushings
Front MM Coil overs (275lb 12" springs)
J&M CC plates
Bilstein 03 Struts
Urethane Rack bushings
MM Steering shaft
255/40/17 9" wheel 5.94 BS

Rear
Bilstein shocks
MM XD Adjustable control arms.
Panhard Bar
H&R White Race Springs
275/40/17 9" wheel 6.40 BS

M-2300-K brake kit on the car.


I want to make the most of what I have and also am planning on cutting off the horrible skimpy BBK Subframe connectors that were on my car when I got her 11 years ago. I have some nice new MM XL subframes to install.

But before I do this I have some questions.

When I installed my coil overs I adjusted the rear spring purches to be exact and the front coil overs the same as well. Well this makes the car lean. I since have adjusted all the points to different levels, making the car mostly level. Within 1/4"

I want to attempt to make the car as straight as possible with even loading on the suspension before cutting off and installing the new subframes.

Also, whats the magic number so to speak for ride height? I struggle on my Camber right now at only 1.1* With them maxed. I did adjust the coil overs so I'd have a much more street friendly ride height. I know that plays a part in getting camber out of the car.

What would be the best steps to take in order to insure that I can make the car straight for the subframes and also the suspension as well. Since I'm going to keep this car forever, till death do us part I'd like to make her straight. The good news is my doors all shut perfect, hatch lines up perfect too. It just feels like the left front tends to dive more on corners? Maybe its just a perception?

Also I'm not sure if I trust anyone local here in my state to do this project. Does MM do these type of things? or are they ridiculously expensive?
 

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MM does not setup cars (at least when I asked about a year ago). They did however say if they're at a track event, they will help.
 

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Optimal corner-weighting will often not come when the car is "level". You'll have to decide what you're willing to sacrifice if push comes to shove. That said, I wouldn't lose a second's sleep over getting that right before welding in new connectors. I just don't believe it'll make a tick's ass-hair of difference in how the car behaves.

It doesn't look like you have an aftermarket K-member or otherwise relocated A-arm pivot points, nor relocated rear pivot points, so personally I'd go with 1 to 1.5 inches max lower than stock, then measure and optimize your bumpsteer. You're going to want 1 to 1.25 degrees of negative camber on the street and more like 2.5 degrees+ on course. I'd shoot for 5 degrees of caster.
 

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Discussion Starter #4 (Edited)
Optimal corner-weighting will often not come when the car is "level". You'll have to decide what you're willing to sacrifice if push comes to shove. That said, I wouldn't lose a second's sleep over getting that right before welding in new connectors. I just don't believe it'll make a tick's ass-hair of difference in how the car behaves.

It doesn't look like you have an aftermarket K-member or otherwise relocated A-arm pivot points, nor relocated rear pivot points, so personally I'd go with 1 to 1.5 inches max lower than stock, then measure and optimize your bumpsteer. You're going to want 1 to 1.25 degrees of negative camber on the street and more like 2.5 degrees+ on course. I'd shoot for 5 degrees of caster.
So MFE Do you recommend I find someone that can help me balance out the car using the adjustable suspension after I cut the old subframes off, then re-weld the new ones on? These BBK ones were installed horribly, one if them has a 1/2" gap on one side. Or should I just do it now as the car sits level? This is just one of those things I really want to make sure I do it right. If a car isn't straight, it won't do anything right even just cruising around. I hear so many conflicting things about how to install sub frames. :crying: Should I just adjust all the perches so they are the same on each side then do the subframes?

Here's how the car sits now. Measurements were taken with the tape on the ground following the axis up through the center of the wheel to the fender. This is with 1/2 tank of fuel, with my sub box in the back. (its about 60lbs-70lbs)

LF 25 3/4" RF 25 7/8"

LR 26.5" RR 26.5"

The most I caster I can get as well is only 2* with the plates totally maxed out. How can I get more. Do I need to elongate the strut holes?

Edit, also the LR Perch is about 1" higher than the passenger side. I can't remember the difference in the front at the moment, but I know the RF is about 1/2 higher adjusted too.
 

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IMO, you should seperate the subframe install from the corner weight. Like MFE said, how the body of the car sits is not relevant to the loading on the tires.

I would install the subframes while the car is loaded "normally". I think MM recommends a drive on rack for this? The point here is not to adjust anything, rather just to lock the chassis together.

After that, corner weigh and align the car properly (bars unhooked, drivers weight in seat, etc).

Equal cross weights may or may not equal a level body and you can decide how important that is to you.

It is an extreme example, but in thoery if you try to adjust corner weight with no subframes, the chassis will just twist more rather than move the weight and then be totally different with the new SFC's.

DaveW
 

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Discussion Starter #6 (Edited)
IMO, you should seperate the subframe install from the corner weight. Like MFE said, how the body of the car sits is not relevant to the loading on the tires.

I would install the subframes while the car is loaded "normally". I think MM recommends a drive on rack for this? The point here is not to adjust anything, rather just to lock the chassis together.

After that, corner weigh and align the car properly (bars unhooked, drivers weight in seat, etc).

Equal cross weights may or may not equal a level body and you can decide how important that is to you.

It is an extreme example, but in thoery if you try to adjust corner weight with no subframes, the chassis will just twist more rather than move the weight and then be totally different with the new SFC's.

DaveW
Okay, so as the car sits level now, chop off the old ones, install the new ones. THEN go get the car balanced out? I've lined up access to a drive on 4 post lift already. :salute: What if my car isn't "straight" so to speak.

Another thing I forgot to mention. The car has had slicks alot over the years and has had a few tears in the torque boxes that were hammered back and welded.

Maybe I'm just putting to much thought into this.
 

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The whole thing is confusing, IMO. And everything with suspension is dependant on something else or a compromise with something else.

The SFC's just keep the front of the car from twisting separate of the rear and makes it act as a single unit (mostly)

If your car is "bent" there really isn't anything you can do about it now. If the doors open and the hatch fits, it is pretty good.

The goal is to lock the chassis down so it doesn't twist any more.

After you accomplish that, then set the corner weights. The end goal here is for there to be an equal amount of weight on the lf/rr as there is on the rf/lr and the tires can't tell the difference if the body is level in order to obtain that. :)

The torque boxes may cause a problem with the overall alignment of the car, especially the thrust angle which should also be corrected. You would want to do this before corner weight as part of correcting the alignment.

Unless your chassis is really tweaked, I would guess that proper corner weights are going to coincide with a mostly level body and all will be good. A 1/4" is a lot of corner weight adjustment, but would be hard to see from fender to fender.

The car is "straight" when all 4 wheels point in the proper direction at the same time and the lf/rr weight equals the rf/lr. The body may or may not be looking straight at the same time, but that is not relevant. :)

DaveW
 

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Discussion Starter #8
Okay that puts it into simple terms and helps me out a ton.

Thank you Dave for taking the time for the reply.

I'm learning as I go here. :) I'll get the ####ty subframes cut off next week and get the new ones installed. Then I'll post back with an update on things. I'm going to take a few days and practice welding as I just got my welder and want the welds to be good.
 
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