The Massive Evo That Couldn't

[Loren]

You've made LOTS of changes to the car over the past few months. I'd suggest giving yourself some time to adapt to it. Learn to not overdrive the slow stuff. Maybe make some minor changes towards fixing your reliability problem (the rear suspension... IMO, that's more important than understeer in slow turns). But, otherwise, just spend some time learning the new setup and fixing your habits where you need to.

After 6 months, if you're still thinking "gee, I wish this pig didn't understeer so much in the tight stuff"... then maybe it's worth looking at how to fix it.

[twistedwankel]

Thoughts?

You seemed happy until you watched the under skirt video. Reviewing your avatar you need better focus

[CaptainSquirts]

Thoughts?

You seemed happy until you watched the under skirt video. Reviewing your avatar you need better focus

that's like saying your tires felt fine until someone pointed out the two nails sticking out of it.

But anywho the changes over made for a little bit now hasn't really changed much except the steering being a little more heavy and the low speed understeer has been something that has been there since the beginning of time but has improved some over the years.

[JasonS]

Subscribed.

Would love to get rid of some myself.

[Native]

Don't forget - there's always compromise.
For example, if you get your car completely neutral on a medium skidpad, and then try to drive it (slower) on a small skidpad, odds are it's gonna understeer (and oversteer on a large (faster) skidpad).
By all means, pursue perfection, but, don't forget...

[twistedwankel]

I always used 1/4" (6mm?) spacers on the front ONLY of my SCCA stock AWD with a stiff rear shock setting and it made a world of difference for turn in. Hubs on AWD are really strong. Never had to replace one in 10 years. Most cars have plenty of threads to allow that (except an 84-85 GSLSE RX7 needed 1/4" longer studs). One guy tried that without changing his studs and lost a wheel at a National event and got his butt chewed + damaged the car. Be warned.

[CaptainSquirts]

So did some measurements of current droop.

- When car is static, it's 25.5 inches from fender to ground.
- When one side is jacked up with wheel just touching the ground it's 29 inches from fender to ground.
- When both sides are jacked up, it's 29 inches from touching the ground.

So at this point, it wasn't the sway bar. But I disconnected one end to see if it made any difference.
- With sway bar disconnected it was still 29 inches when that side was lifted and tire just barley touching the ground.

So at this point I was surprised so that means either it is an arm that isn't allowing the extra travel or the droop is maxed out. So I checked the helper and that sucker was at full rebound. So in the process of checking all this stuff out I had ordered some new rear springs last week so I went ahead and took out the rear shocks since it was all right there anyways. The rear suspension didn't move much at all anymore when I took my coilovers out, so an arm or something was at its limits also on how much it could move.

To me it looked like it might've been from the upper control arm, the U shaped joint. When I would try to push the rear hub down, it would go down a little and bounce back up. I did some research and the front bushing(view pic) on that bushings is bonded to the shaft that goes through it. "It acts as a spring in rotation to both limit the travel for geometry reasons and help stiffen the rear in spring rate."

Anywho I know I could loosen the ball joint and release it from the hub but I don't got a ball joint remover and I didn't want to go through the hassle of smacking the crap out of the hunk of metal next to it to shock it out so I'm not going to worry about it. Now since I pretty much have all my replacement bushings, the new one isn't bonded but has a pivot bolt so it'll have more free movement. Regardless I would need more droop and I do not have enough stroke left in the shock itself so I'm done on trying to have ALL the droop . In the end, I got more droop and I think at this point if I wanted to fix it I would need stiffer springs in the rear to not have as much roll, I think.

P.S since I got stiffer rear springs I might swap the current 616lb springs in the rear and swap them to the front which are 560lb springs since there is a ton of body roll at the front.

[Loren]

Soooo... Am I reading that your droop limitation is actually the shock stroke?

Stiffer front springs can actually help. Resisting compression on the front corner will effectively resist lift on the opposite corner. If nothing else, it will feel more controlled diving into a turn.

Not gonna help that low speed right turn understeer problem, though. (I think you just have to drive around that)

[CaptainSquirts]

Soooo... Am I reading that your droop limitation is actually the shock stroke?

Not 100% sure what you mean but pretty much I have 3 1/2 total stroke (is 4 1/2 but rubber stopper is 1inch tall). At static, my main spring will compress by 1", my helper will compress fully at 1.5". So I have 2.5" droop at the shock and 1" compression. Makes me wonder if I'm hitting the little rubber stopper thingy when all the weight is on that corner in the rear. I haven't really noticed it though.

Also I believe it's limited from the upper control arm as well due to the front bushing but at the point the bushing is stopping any more droop the droop from the shock has all been used up.

Question. When turning, does the rear corner that is taking all the weight just get it from the other side of the rear of does it get some of the front as well?

[CaptainSquirts]

Got the new rear springs installed. Went from 616lb to 700lb springs.

tl;dr - installed new springs, regular driving didn't feel any more harsh, rear ride height is higher, need to let spring settle in and then change it to match what I had prior(change of mind, keeping it as is).

First impression, the rear sat at a little over 26 inches(static, havent driven or done anything yet) compared to 25.5 inches(when drivin and settled in). I got into the rear seat and started bouncing to help settle them in some. It went down to 26 inches. Drove around and it didn't really feel any more harsh but time will tell. After the first drive it sat at like 25 7/8 inches. Going to work I remeasured and it has dropped down to 25 3/4 inches. I would like to get it back to 25 1/2 inches but I can't see the spring settling anymore but I doubt it, since by mathing, it should have about 1/8th less compression. So I'll probably lower the rear back down in a day or so to keep the geometry the same as before. Now on my way to work, at a non crowded empty road I did spiritedly took the corner and the rear felt different. Normally my rear kinda just follows the front, but this time the felt like it was coming out/rotating more in the rear. Not in a bad snap oversteer way but more of a gradual hey, im slowly swinging around if that makes any sense....

Well, can't wait to see how it reacts at the slalomcross this weekend!

P.S Rechecked height again, dropped to 25 5/8th after more driving. Not going to change the ride height for a 1/8th difference. My math checks out at least since I should have 1/8" less compression and I sit 1/8th higher on previous springs. Suspension stuff more and more fun the more you learn and make sense of it.

[Loren]

[twistedwankel]

https://www.bing.com/videos/search?q=ut ... &FORM=VIRE
Someone caught you shaking down your suspension.

[CaptainSquirts]

https://www.bing.com/videos/search?q=ut ... &FORM=VIRE
Someone caught you shaking down your suspension.

Damn, I've been doing it wrong apparently.

[CaptainSquirts]

Went to Joe B's place and got some bushing goodies installed. I went all polyurethane besides the lower control arm which is rubber spherical bushings from factory so I put new OEM one in there. The toe arm bushing is offset to combat the bumpsteer from having the rear lowered. Took about 6 hours to get everything off and installed. 12 bushings overall.

Dunno how it'll be performance wise but from a comfort perspective I didn't notice any harshness and it almost feels better if I'd say.

Lower control arm and rear upper control arm.

Upper control arm front bushing. This needed to be burned out, was a bish to get out.

Offset toe bushing as you can see it being, well, offset from the centrr.

[Loren]

[CaptainSquirts]

Just random thoughts.

So I'm reading on Lorens control extended balljoint mod he did from his Mirage. Roll center on the front of the Evo sucks and basically the car has to sit high for the roll center to not go underground. With 10k springs, I still have a nice chunk of body roll. The car has to pretty much be near stock height even with a slightly taller ball joint that I have with whiteline to "fix" it. The Whiteline is only 3/16th of an inch taller than oem, so not much.... The center of gravity sits high, can't really lower the car much at all due to control arms pretty much parallel to the ground and lowering it more would make the RC go underground(which I did when I first installed the coilovers and it understeer'd so easily).

Only real options I can think of is
a. get one of those fancy billet fabs some people make which are big $$$.
b. Trying to find a taller ball joint that can fit inside my current control arms.



But I think the easier route for the time being is throwing on a pair of springs that are 50lbs stiffer than the current one, but also doing a mod on the front sway bar to make it a little more stiff which will reduce the body roll.

[Loren]

Time to take a few measurments, plug them in, and then start playing "what if" games.

http://vsusp.com

Taller ball joint, longer control arm, raising the inner pivot point (perhaps with an offset bushing?), etc, etc.

[CaptainSquirts]

Installed new front sway bar brackets. Will make the front sway bar 16% stiffer which should help a little bit with the front body roll. It might even help with the rear lift a little but we'll see at the next open event. Praying to the sky gods for no rain.

Top stock, bottom aftermarket

Stock

New bracket installed

[Loren]

I'm not sure I believe that changing the end link bracket is going to make your swaybar stiffer.

But, I guess the way it's mounted, moving the pickup point further out on the control arm gives the wheel less leverage on the bar, which would make the bar more effective... and it would FEEL stiffer. Which is effectively the same thing.

I don't like the weird angle that it puts your end link at. Seems like it would put a side-load on your swaybar. If your swaybar doesn't have a means to keep itself centered in the bushings, you might want to keep an eye on that.

[CaptainSquirts]

People use the stock endlinks and have no problems with it. Stock ones are so tiny compared to the aftermarket ones I have. But regardless will keep an eye out.