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I've probably put my Grand Prix through the ringer more in the past decade than anyone else on this forum and, at least for first gen cars, I feel the springs are the weakest link for how they handle. My car has the sportier FE3 suspension and the amount of body roll is still really high. I have a few pictures of it during track days while in a corner and while it doesn't look that bad I can say that you really do feel all the weight being thrown to the outside of the car. Braking is similar, you feel all the weight getting transferred to the front wheels during an aggressive stop and I've had the back end slide out from behind me a few times because of it. I think the best way to improve the handling for these cars is stiffer springs and better tires, but good luck finding a shop that will fabricate a new monoleaf for you. I will also add that I do think dropping the car by an inch or so will help so long as you have camber bolts or some other way to adjust the angle the wheels are sitting at, the center of gravity in these cars isn't that bad but it could be better.

First let me say that anyone should do as they wish, obviously, with their own car! That said, I believe it’s important for proper information in making decisions that affect not just the performance of such choices, but safety. Most will pass over this as just so much yada yada, but those that understand engineering, physics, the principles of energy & much more may take a moment to read & think about this. Recently there was a mention in a post about the lowering of the W-body’s! It was stated that such a choice was a bad idea & I concurred, but I would leave it there at that time! I would like to address those reasons here!  Reasons many people believe lowering a car's unsprung suspension is a good idea & will help a car handle better often comes from others who make assumptions & never do the math, really don’t understand the entire physics involved or know how to do the real work that is required to know what their actual numbers are & never truly put the car to a real test to prove it out! Yes they may take that car around a corner faster or it may corner flatter at the same speed as before & it feels good, but what if they really had to push it? So the first fact, & you can research this yourself, is a double wishbone suspension & a macpherson strut suspension are worlds apart. The first can be infinitely fine tuned. The latter can’t! The first has many components that can be adjusted to affect roll center. The latter does not. With a  double wishbone you can change caster, a lot, you can change camber a lot. You can effectively do a combination of movement of both caster & camber forward & out or in or rearward & out or in whichever you chose. With combinations to create many performance effects & these are just two parameters that affect suspension physics. With many double wishbone suspension you can find lowering spindles! This allows changes to the geometry of the lowered suspension with regards to CG while allowing RC to remain unchanged or altered whichever you chose. For the simplistic explanation, this amounts to the car being lowered, but roll center remains the same,with proper adjustments, as does suspension travel!  In a Macpherson strut suspension this does not happen. There is no simple way to change caster! Camber you can, but it has limitations compared to a double wishbone. There are no lowering knuckles for Macpherson suspension for obvious reasons! The bearings are so large there is no room to alter the knuckles. As a result, suspension travel is negatively impacted. Roll center changes negatively, in a bad way automatically & you can’t do much to alter it. Then there is this. How many truly know what their roll center is? How many know how to figure it? Better yet, how many of you can do your own wheel alignment? If all you did was put in lowering springs, & as such the car seems to corner better; then the answer to the above is you don’t know! This means if you were ever to be in a situation of needing to maneuver excessively quick, at a higher speed you might find yourself in serious trouble!  In finality, suspensions are very complicated. There are over 100 mathematical calculations involved in setting up just a front suspension! Instant center, roll center, center of gravity, jacking force, anti jacking force, etc… to name just a few! In the end you can make an FWD handle! Not just well, but high end sports car well! But, not by lowering the car!

And a few years later and I'm finally building a proper exhaust for it. I bought a universal kit off Amazon and put this together this weekend, along with a couple used Borla mufflers that were given to me. It's louder than I was expecting, but is mostly just too much bass and rumble for my liking. I attribute it to the 3 inch pipe and straight through design of the mufflers. I have since ordered a smaller inline chambered muffler that I'm going to install where the factory cat/ resonator were installed to see if it tones down the deep rumble a bit. Aside from that, does anyone know where I can get new or like new OEM looking exhaust tips for this car or have recommendations for a lookalike? I'd certainly appreciate any suggestions but ideally would like to copy the original style.

I'm sure everyone will have their own opinion here, but if you want to keep a stock sound I would highly suggest a Walker Muffler. I had them on my 3.1l Grand prix and I think they sounded better than the rusted out stock muffler, and restored the original sound.  https://www.walkerexhaust.com/ And here is a Youtube video with a Walker Muffler on a Pontiac 6000. To each their own, if you don't like this, there are plenty of other options. I really like Magnaflow mufflers as well and have those on my GTP, and my old 3.4l Cutlass.   

Hi everyone. I’m restoring my 90 olds cutlass , the car is all original. Still has stock muffler. But I’m pretty sure it’s on it way out. My question is if there are any mufflers that won’t take away from that 3.1 raspy sound. That exhaust tone is nostalgic.