Advanced Suspension Mods

[jemartin144]

My race car only has about an inch of total suspension travel in the rear, so I would say it has very little travel. I'm not an expert when it comes to suspension setup, but I've always thought that for most front wheel drive cars you tune handling primarily though rear roll. Most front wheel drive cars understeer naturally. So, while more rear roll stiffness is desirable, there is a point where you could make it too stiff and start to get oversteer. The amount of roll stiffness you have in the rear is affected by the front also. So, if you're running a completely stock suspension in the front and go crazy with roll stiffness in the rear you are going to be sliding the rear end all of the place.

This is why a removable sway bar can be a good solution. After you get the stiffness to a good neutral place you can tune in how much roll stiffness you want depending on the track and conditions. ie, in the wet there is less grip, so you would run with less roll to maximize grip. Now less adjustability only really applies if you're running in different conditions and need to tune finitely. In most instances this isn't the case and you can just find a good balance for your setup and leave it that way.

[russian]

Rather than running a sway bar I chose to reduce the amount of static sag (or droop depending on the school of suspension theory you subscribe to). When you reduce the amount of suspension sag to only what is necessary (especially on a trailing beam suspension) you limit the amount of body roll. Sway bars are necessary when you need a lot of suspension travel and you need to control that travel in corners i.e. street cars that travel rough roads, off road vehicles, and heavy cars. The most efficient way to control body roll on the festive is to reduce static suspension sag, but for those of us that don't have perfectly flat roads (my roots are in the western foothills of Maine, where nasty tarmac is almost smoother than the dirt washboards) a good setup would be to use a bar that follows the profile of the rear beam that has adjustable end links, similar to a bar for a mk1 VW.

pictures of the said bar?

here are the details on super pro bushings - http://www.fordfestiva.com/forums/sh...4&postcount=20

[TominMO]

Any ideas on stiffening the rear side? Like do we want a sway bar in the back? Or do we want steel angles welded to the torsion beam?

There's the 5/8" threaded-bar mod. Stiffens up the rear beam noticably.

[Advancedynamix]

Rather than running a sway bar I chose to reduce the amount of static sag (or droop depending on the school of suspension theory you subscribe to). When you reduce the amount of suspension sag to only what is necessary (especially on a trailing beam suspension) you limit the amount of body roll. Sway bars are necessary when you need a lot of suspension travel and you need to control that travel in corners i.e. street cars that travel rough roads, off road vehicles, and heavy cars. The most efficient way to control body roll on the festive is to reduce static suspension sag, but for those of us that don't have perfectly flat roads (my roots are in the western foothills of Maine, where nasty tarmac is almost smoother than the dirt washboards) a good setup would be to use a bar that follows the profile of the rear beam that has adjustable end links, similar to a bar for a mk1 VW.

[jemartin144]

On my racecar the previous owner used a civic roll bar in the rear to improve handling. He made brackets for it to mount in the rear near the bumper and then it bolts up to the beam. He did it that way so that he could choose to run with or without the stiffer rear. In the dry he usually ran with it, in the wet without it. This is with all stock suspension, except coilovers, btw.

[russian]

Any ideas on stiffening the rear side? Like do we want a sway bar in the back? Or do we want steel angles welded to the torsion beam?

[Advancedynamix]

If you're addressing me, I was pretty happy with the stock springs; it seemed to be all about the superior dampening of the GR2s. I compared the Monroe and GR2 side by side off the car, and the Monroe has both a thicker shaft and heavier dampening.

I found the stock rear spring rate to be a great street rate as well. With the car stripped out it handled great with gr2s and stock springs. When I cut my stock springs it sat lower and was slightly stiffer, but didn't handle better. It actually had more body roll.

[Advancedynamix]

Tom, I would be interested in that, but it would be better if we could get at least ten people interested. That way I could have the sleeves machined instead of buying them and I could probably get a better deal on the shocks and springs. Without the discounts it works out to being around $250 not including the price of the shocks.

[TominMO]

^^ Correction to the above: the KYB has the thicker shaft and heavier dampening!

[TominMO]

I wonder if a stiffer spring would help?

If you're addressing me, I was pretty happy with the stock springs; it seemed to be all about the superior dampening of the GR2s. I compared the Monroe and GR2 side by side off the car, and the Monroe has both a thicker shaft and heavier dampening.

[zoom zoom]

I wonder if a stiffer spring would help?

[TominMO]

Have you tried monroes? I was thinking about going with them since they're a little cheaper and I'm a tightwad. Just wondering what the difference would be, the dampening properties?

Zoom, I had KYB GR2s front and rear on my Festy, but had to switch to Monroes on the rear for the higher spring perch, when I installed wider tires. They are definitely inferior to the KYBs. I'm even thinking of going to lower-profile 14s all around, or even 13s on just the rear, to allow me to stick GR2s back on.

Charlie, would you be willing to entertain the idea of duplicating a pair of rear GR2s for those of us without your fab knowledge/skills/tools? I'm thinking, send you the $$ for all the parts and shipping costs to me, plus a reasonable profit, then patiently wait until the struts arrive on my doorstep. I hate my Monroes.

[BigElCat]

FYI

Moog makes a sway bar to LCA bushing that is much stiffer than rubber. It may be polyurethane, but it seems even 'stiffer' than other polyurethane bushings I've seen. They're blue in color. Part number K9737. I haven't used these so far, but I will someday. O'reilly sells them for $10.00 a side.

[Advancedynamix]

Good information for sure! Did you have to call them to order? I found the parts on their site, but I'm not sure how to order them. Might be because I'm on my phone. Thanks for the info. Post pictures of them when you install them.

[russian]

I have recently received poly front sway bar bushing - SPF1478-22K - shipped from Australia, ordered via Tein USA. They are direct fit for stock festiva sway bar.

Will update the old poly bushing thread which pointed me to them as soon as I receive the sway bar to LCA bushing.