Secrets of the Mirage

[Loren]

Did I ever mention that I should have bought a 2017 instead of a 2015? I didn't realize this until after I bought it. I knew they had made some cosmetic changes (that I didn't really care for or about) for 2017, but I thought the rest of the car was the same. Turns out they made some improvements.

2012-15 has 74 hp / 74 tq
2017 has 78 hp / 74 tq (changed to roller valve train)

2017 has stiffer rear springs and revalved shocks all around. Everything else is the same.

2017 has some kind of front chassis stiffener. Need to find out what.

2017 has larger front brake rotors, different calipers, and different pad compound. (same pad shape, though)

Nothing that's worth the $3,000 more I'd have had to pay for a 2017 model. The only thing I might want is the larger front brakes if the car ends up feeling under-braked.

[Loren]

Installed the rear shocks the other day. Pretty significant difference in the handling. Unfortunately, also a significant difference in noise and harshness. The old shocks weren't quite dead. They had some damping, but if you compressed and then extended them, there's was a big ol' dead spot in the middle. THAT is what I felt when driving it, it was awful. The new shocks are just very stiff. Even on full soft, they're very stiff and responsive. And they have very little bushing material on the bottom eye end, which makes them a little more harsh. And I had to "cheat" the upper shock rod mounting a little bit. I put a half inch stack of washers below the top bushing to effectively make the mounting point on the shaft a half inch taller. There's enough threads on the end of the shock to deal with that. But, I compromised the way the upper bushings mount, and I can't fully tighten the top nut against the steel insert (that goes inside the bushings). So, there's a little rattle over bumps, and that's probably what it is. Need to revisit that. (a 1/4" longer bushing insert would fix it... if I can find such a piece)

The rear swaybar is done! Big thanks to Joe Brannon for his help fabricating it. It ended up being a pretty simple and efficient design. It's definitely over-built. As long as the welds hold, I have no concerns of it ever breaking. I have some grinding to do to clean up the edges and some welds, and then it needs paint. But, it's done, installed, and works nicely! The car still has roll (the front suspension has not been improved, so it still rolls in the front), but it feels a lot more precise and planted.

Here's a photo of the Rear Swaybar if you want to play Where's Waldo with it. It doesn't exactly stand out, but if you zoom in, you can see it. We opted to weld mounting plates to the lower spring perch just because it was easier to do than making it a purely "bolt-in" application. The bar still bolts to that point, we just welded on the mounting plate instead of putting it under the spring and making it a "sandwich" plate.

[Loren]

Also got a good look at the front swaybar today. It's pretty crazy! The arms go up and over the steering rack, back down to the center mounts on the subframe, and in between those two mounts, it goes UP over the exhaust!

No easy way to mod that bar to make it stiffer.

But, the front struts on the new coilover kit are CRAZY stiff. If we can get those adapted to the car, I think it will take care of the front stiffness just fine. May start on that project Friday.

Just spent an hour with a grinder cleaning up the rear swaybar and priming it. Should have it painted and back on the car tomorrow. Woohoo!

[Native]

That's a nice clean job! Paint the bar to match the shocks. Which by the way have more diameter than the exhaust. Lol.

[twistedwankel]

Looks a lot like a Foxbody suspension. Drew's car is broken last I heard. I never though you'd have bought a less than totally researched Mr Bitchi. You are losing your Soul/Kia. What will you do when someone develops a KIA? OMG. Loren is vulnerable. KIA means "kill" in Greek.

[twistedwankel]

If you put RE 71's on a turd will it exit better? The Iron I'm taking tends to back me up. I only need more Iron since I sold my wife's Vette.

[Solar]

Looks good, nice "engineering" job there. I'm assuming the next project is painting the brake calipers to match the shocks and struts, thats very important.

[ImpostorDan]

This thread makes me want to put RE71s and a sway bar on the volt.

[Loren]

Started looking at the front suspension today. Looks like everything should work.



In the photo is almost everything we're going to use. Notice the nicely fitted upper spring perch at the top of the spring? That's a factory piece, but it's only present at the top. I'm going to order another pair of those, and we're going to have to modify them by cutting off the end so that it will sit neatly around the 2.5" coilover spring perch. With those at the top and bottom, it will all fit together brilliantly with the nylon spring seats and all... and probably not even rattle! Of course, the stock springs are under at least 3" of compression at stock ride height, so it shouldn't rattle, anyway.

There's enough adjustment in the shock length and the spring perch height for this all to work. We test-fitted the bare shock with all the spring perches in place, plenty of tire clearance. So, once I get my hands on those stock spring perch parts, we're good to go!

The front struts are even more stupid stiff than the rear shocks. It's going to be a VERY firm ride with this suspension. Hopefully, it will have the desired results.

The stock front struts aren't quite as bad as the rears were. They don't have that big vague dead spot between compression and extension. But, they're pretty soft compared to the coilover struts.

[Loren]

Oh, and I painted the rear swaybar with leftover Festiva teal fender paint. Now the underside of my Mirage looks like a baby shower. Pale Blue and Pink.

I expect Philip will get some great photos of that at some point.

[twistedwankel]

Looks like there's 9" of threaded adjustment. These must be one size fits all?

[Loren]

I'm sure the shock bodies are universal. They change the valving slightly according to spring rate. Maybe.

[Loren]

Added some suspension reference info to the first post if anyone is interested. Mostly just measurements taken of the stock shocks/struts and their replacements.

The big problem with trying to fit the stock springs to the coilover shocks is the loss of shock stroke length. Going from 5.5" to 4" in front and from 8" to 5" in the rear. I hope I don't end up destroying the shocks with this experiement!

It seems like it will be more of a problem in the rear where I'm left with about 1" of extension travel, and 3.5" of compression travel. So, any significant bump or hump that I hit, when the suspension recovers from the bump, the rear shock tops out with a little clunk. (and if the back end completely lifts on one side or the other, it crashes back down again) Compression isn't a problem, it handles that well. I'll have to experiment with what making the shocks firmer does to that. I suspect it's not really going to help it... it will likely actually make things harsher (though it might be better for the longevity of the shocks).

In the front, less travel has been lost, and with the weight up there, extension won't be as much of a problem. So, if I can set it with 1.5" extension and 2.5" compression, it should work. The shocks are stiff enough that it should keep things from being "crashy" over bumps. I hope.

Bottom line is that if I set the shocks as firm as they need to be, it's going to be a firm, borderline harsh ride. Not what I want, really... but, that's my sacrifice for staying in stock right now. If I went to M4, then I could have more appropriate spring rates for the amount of shock travel, set the ride height lower, and probably end up with a better ride AND better handling.

[Solar]

Sounds like you might want to consider just using the springs they came with and run in M4, that's a lot of force being applied to the shocks on the rebound stroke, you will kill the seals and could break the stem.

If it were me, I'd run them with the matched springs for a year or so and then try using the OEM springs later on, that way at least you will get your money out if them, I'd hate to see them go south on you in a month or so.

[twistedwankel]

Shush. Loren said at the Awards Ceremony that he will be an old man when he drives a Crown Vic.
He forgot about a Corvette with the required "bimbo". Such a child.

Not only do I have one of each. I belong to the "Rotary"

[Loren]

I started tweaking the rear shock settings today. Was running them full soft using the logic that "that's all the stock springs should need".

But, it was kinda clunky. And a lot of the clunking, I'm pretty sure was the shock reaching its extension limit. (I still expect that a rear shock for a FWD car should be DESIGNED to handle that, as there's no way the car WON'T 3-wheel with a stiff coilover kit on it... but, I don't like clunks)

I think I have 16 clicks of adjustment. Something like that. So, I started by going 6 clicks from soft. Didn't really feel a whole lot different, but it did clunk just a little less. Good. I went another 6 clicks, so now I'm at 12/16 or 3/4 stiff. BINGO! The clunk is pretty much gone, and the car feels a lot more composed.

Can't wait to get the front struts on there! Hope to have it ready for the 9/9 Dunnellon event.

[Loren]

So with the click settings, how do you tell if you have them set correctly with the click adjustments? Also would that settings be good at autocross or would you have to adjust it just for autocross and then back for regular Daily driving?

I'm gonna put this question in a new thread. (yeah, it's that complicated)

[Loren]

Went over to Joe's Garage today and we got the front shocks installed. I need to do some fine tuning of ride height and alignment. (I think one side is slightly too high, the other is slightly too low, go figure... and camber is about -1.9 on the left and -3.1 on the right) But, the shocks feel SO nice! Turn-in is crisp, everything feels settled, the diiiiive under braking is gone, etc. All the things you expect when you go from crappy shocks to good shocks.

While we were there, we put the car on Joe's scales. Didn't level anything, just a rough weight. 2057 pounds as it sits. Figure the wheel and tire package probably added 20+ pounds. The rear swaybar probably 15 or so. That puts factory weight just a tick over 2000, right where it should be. Front/Rear bias is 59/41. Not bad for a FWD car. Didn't document it, but Joe said the left/right balance was really close with me in the Driver's seat, but a little more weight on the front.

Aside from getting the ride height back to stock and tweaking the alignment, I'm thinking about reworking the rear swaybar. Believe it or not, I think I actually went too stiff with it. Probably won't be bad for autocross. Handles nicely, really. But, for street use, it rides like an ox cart. The rear suspension goes ka-thunk over every little bump. Aside from being annoying, it's probably needlessly beating up the car.

[AScoda]

it rides like an ox cart.

I'll defer to the wisdom of your advanced age and experience gained from the many hours you've spent riding around in ox carts, and assume that this is a non-desirable condition.

it's probably needlessly beating up the car.

I think that is a key aspect of autocross.

[Loren]

Drawing on experienced gained from the FASTiva, which also had an overly-stiffened twist beam axle... in addition to completely eliminating any sort of "independence" in the rear suspension, this can also lead to stress fractures at whatever location is the weak link in the system. That's what I'd like to avoid.