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Exhaust v1.2. I wasn't happy with how loud it turned out despite the mufflers. I'm sure the 3" exhaust isn't quieting it down at all, but the mufflers are Borla Pro XS which are supposed to be a "quieter" muffler. So, I added a inline chambered muffler from Remco which toned it down a bit. It sounds less like a dumpy bass drum now. The reason for the 3" is that I plan on going turbo next year and figured I'd set myself up for it.

I’m including another article by Huibert Mees. In this article he explains why lowering a car even 1” can have substantially negative effects. All things I have said for decades as well as here recently. The one thing that is not touched upon is lowering the CG without lowering the car!! What happens then? I explain this in my member's post, last Indian, a ground pounder build. The short version is there are ways to move weight & add weight all below CG. When this is done correctly this lowers the CG in a good way without impacting roll centers or suspension travel! And in doing so you may be able to move weight in such a manner like I did to affect weight distribution as well, depending on how you do it. https://www.theautopian.com/heres-how-lowering-a-car-can-ruin-its-handling/

Probably just due to manufacturing issues or Chevy didn't have a need for a car that sized right away in 1988. There were no sedans in 1988 only coupes. Sedans started in 1990 so that might have something to do with it. GM had a lot of issues getting production going with these cars back then. Doraville, GA is where the Cutlass Supreme and later the Lumina in 1990 were assembled. There was a massive retooling going on and there were issues on the line. These cars were all new and GM already put billions into getting these cars built. GM did have the Beretta at the time, so the need for another coupe in 1988 probably wasn't too high on the list.

So I will first start by recognizing that most will doubt what is presented here so I will attach links to some videos from Huibert Mees. He is a renowned suspension engineer, who has done chassis designs for Ford, Tesla & others. I refer back to my earlier post. Most think they know suspension, they think springs, struts, sway bars, (but never think of link ends) & maybe a few other things! And as such think they understand how to build a suspension. If the body rolls it must be springs or CG! So the first order of business; they lower the car’s CG by using a shorter spring! Terrible idea! Why? Even an inch or two down impacts the roll center negatively, while reducing the suspension travel! I am not comparing myself to Huibert Mees, but I have designed suspensions among many other mechanical devices for more than 50 years & have many patents. So I’m not trying to garner accolades. There are so many things to look at with a suspension, but if I pick just one thing to affect cornering & more specifically high speed cornering, it would be sway bars & their end link! Yet many ignore sway bars as a remedy. Even more so, most never consider their relative size vs end link size! If, I simply said to you, have you ever heard of Archimedes & his statement of "Give me a lever long enough and a fulcrum on which to place it, and I shall move the world." You most likely would say yes! Well to a degree this is your sway bar & end links! Do you honestly think a bar, aka lever, 4 feet or longer & ¾” or more in diameter; in some cases as much as 1 5/16”; can be effectively applied by a secondary lever that is more than 3x smaller!? In some cases like the solid aftermarket front bar of the W-body ll more than 4x smaller. If you did the section modulus of the two you would find the numbers even more staggering! Amanita, without seeing your setup I would be guessing, but by your pictures several things appear to be part of the cause, but all point possibly to two issues. The sway bar & weight distribution. It has been many years since I have worked on one of the first gen W-bodies. So please correct me where I am wrong. Doesn’t the front bar end point attach into a u bracket & rubber bushing? Similar to how the bar attaches to both sides of the frame? If so, the bar as the rectification point! I can explain how. The second is the weight distribution. These cars, as most should know, have a horrible weight distribution. Again there are ways to affect this if you want to put in the work. Last the rear leaf. This can be improved, but it will take work & if you can’t do that work I doubt it is worth it to you to pay to have it done. Last I will attach some pictures, sketches & links that may explain things better, especially the jacking force. The picture of you car is presenting your jacking issue.

Ive had about 10 Luminas in the family starting in '90. The '91 we bought in '95 was a base w/14s. Ive put those base wheels on 2 of our '90s & my current '93, often keeping an OE 14" steelie in place of the donut as a highway-worthy spare tire upgrade. I didnt know this was a surprise to anyone. 1st Lumina steelies are all 14". Alloy upgrades were 15" or 16". Same brakes from '90-'94.

Well, I completed my front brake upgrade, gone are the 10 1/2" rotors & in their retired place are a pair of 12" rotors. My approach for this was to maintain the original W calipers & just install larger dia rotors in the same manner that GM did when replacing the 10 1/2" rotors with 11 1/4" rotors. The W calipers are more than adequate on their own merits. The 11 1/4" calipers are pushed further out from center by a later design in the caliper bracket adapter. Seeing as I didn't want to purchase & then alter the 95-96 adapters I reconfigured what I had on the car. To do this alteration one has to remove the adapter that is welded to the steering knuckle. One has to cut away the outer section of the *ears* that the caliper bracket is bolted to. I sourced a length of 1/4"x2"x 12" A36 hot rolled mild steel flatbar, this bar is already stronger than the stamping of the adapters & the flatbar is thicker than the adapter by .050 thou. Starting with the drivers side which being done 1st served as the guinea pig for any mistakes I know I would make. I cut off the adapter, gave it a blasting, laid it out on a workbench & proceeded to mock up what the new longer *ears* would look like to get what was needed. Out of the 12" of flatbar I cut 4 *ears* each the same size, from there I laid out on each one the location where I would need to drill the 9/16 hole for the thru bolt. The *ears* have to be shaped into a circular manner on their edge so as to fit into the valley on the backside of the caliper brackets & be able for me to pivot them to get the appropriate angle before tacking them to the adapter. This mod requires that the new *ears* be overlaid onto the backside surface of the adapter. The new rotors *hat* is 1/4" deeper than the original rotor so the need for 1/4" flatbar to move the caliper back inward to get the proper location for the new rotors. Now the adapter has to be fastened back into place on the knuckle behind the hub assembly, install the new rotor onto the hub & lock it into place with a couple of wheel nuts, bolting loosely the *ears* to the cast caliper bracket I can now place the bracket over the rotor to get an approx location where the position will be that is the same as the original caliper was placed. I now install the caliper & the new pads into the bracket & slide the entire assembly over the new rotor, getting an accurate height position for the caliper on the rotor I now need to check that all of the caliper pad is contacting the rotor face. Seeing as the 12" rotor has a larger diameter one needs to make sure that the outer edge of the rotor will clear the inside edge of the stationary bracket but get all of the caliper pad on the rotor surface. I had to remove the brackets & mount them into a bench vise an carefully remove approx .030 tho of surface inside the very upper edge of the upper & very bottom edge of the lower portion to expand the radius to get the needed rotor clearance as it spins inside the stationary bracket. After doing this I can now reinstall the assembly, position the assembled caliper & bracket, position the new *ears* over the cut off ends of the adapter, tighten down the bolts to hold the *ears* where I want them & now tack the upper & lower *ear* into position. I repeated this same procedure for the right side but it went much faster seeing that after completing the left side I now have a template use for the right side. The welding was simple, remove everything from the car, bolt the cast caliper bracket to the adapter to prevent the adapter from warping while welding, mount them into a vise and run the beads, a flat downhand is best for this, the 71M wire puts down a nice wide bead to get maximum coverage for strength in a single pass. This welding procedure requires a minimum of a 200 amp mig, the wire I used was a deep penetration fabrication flux core wire for argon/c02 for heavy fab work such as construction/ship building. A 70S is not recommended. After getting everything assembled back together the last thin to cover is the new rotors hub opening, the W hubs are 70mm dia, the new rotors are 71 mm opening, this means that a 1mm shim is required to slide into the center of the rotor to properly center it over the hub. This was relatively easy, I pick up some 1mm stainless sheet steel & cut two shims 1/4" wide & to length & slipped them into the center of the rotor around the hub stub, then slide the rotor onto the hub. Worked perfect. It's been 2 weeks now since completion, after bedding in the new pads I have done some mild to moderate brake stops, working up to a few panic stops. The difference is instantly noticeable. The car just hauls down to a stop in a much quicker, shorter amount of time. Now since a few years ago when I did the booster upgrade the pedal feel at that time was instantly changed. Going from a hard, less than desirable *no assist* feel to a one can literally stop the car by using ones hand on the brake pedal, the booster supplies so much assist the pedal is like a feather to press. The pads because of their shape do not cover the entire rotor contact face, approx 70% of the rotor surface is made use of & that's the outer portion of the rotor. I have to believe that the smaller 11 1/4" rotors see this as well, not having had any in my hands to compare the contact area with the 10 1/2" rotors I'm pretty sure that THOSE rotors may have a larger dia hat area that reduces the contact area to something similar to the 10 1/2" rotors, these Ford Crown Vic rotors have a *hat* area that is the same as the 10 1/2" rotor hat. All in all...well worth my time & effort & what did it cost me? ...the price of a pair of new rotors & pads & a length of flatbar.