[Mattman]

I'm getting 18x10 and 18x9 FR500's. I have the eibach pro-kit installed, so i shouldn't have this issue also should i?

[rfcsoulja]

From personal experience. The smaller the tire size, the more road you feel. Think about it, rubber absorbes impacts as well. Less rubber= less absorbed. Metal doesn't absorb anything, just transfers it. So I don't think it's neccesarily the rim size, but the tire size that affects how a car drives (along with shocks/struts and springs of course).

[Mattman]

cool thanks bro

[Zatrekaz]

I think the cause is the tires. However it's over $600 for 4 new ones. Gonna have to wait awhile for that

[Mattman]

Dang that sucks

[goren420]

Ok I'll attack this... vibrations/rough ride can be caused by numerous things. Low pro tires are one of them, with bigger rims on our cars you have to go smaller rubber, so you'll feel more road, this is a con of bigger wheels...

Next for the mod list you gave, really won't stiffen the road feel in straight line driving, for curves it'll be nicer... I don't have subframe connectors yet, so those I'm not positive about, but the front strut brace you won't even feel a difference really unless you use it for awhile then take it off, it's nice for curves, autocross type driving where your shifting the car's weight back and forth, those braces just reduce frame flexing.

To 'stiffen' (dampen) the suspension and make for more comfortable driving, you're best bet is shocks/struts. I have tokico HP's which are the first step above stock. For greater feel at a higher price go after an adjustable set, like Koni's or the Tokico D-specs. That way you can choose the setting that suits you best, but as always it's pay to play. I love the feel of the HP's on prokit springs, and I have 18's, the ride is great.

Other things that may cause these vibrations can be brake rotors, they may warp over time and at higher speeds you'll feel it more. Also your steering rack may be worn causing wheel shake. If you're going to be doing suspension mods I would do the whole thing, springs, shocks/struts, CC plates, the braces and maybe even bumpsteer kit. As always when changing one thing (rim/wheel size) you'll need to make some other changes to have it all work right (comfortably).

[goren420]

Oh and as far as installing the strut brace... it wasn't too bad, drill the necessary holes, debur them. You'll have to remove and cut out a section of the plastic piece covering the firewall. To connect the bolts onto the firewall, you need either really skinny arms/fingers or some ingenious custom tool. There are a few openings once you remove the plastic cowl and firewall pieces to squeeze your hand into to hold a wrench on while someone else tightens the bolts. Somewhat tedious but not hard. (It will fit with caster/camber plates if you're wondering that was a question I had when I installed everything).

PM me with any other questions I've done most everything on the suspension besides subframe connectors and upper/lower control arms (coming soon...)

[Zatrekaz]

I do remember when I changes my brake pads my rotors were very bad. They had been grinded down alot due to the pads going bad. That would cause vibration throughout the entire car enough to make driving more diffucult? I will have a shop check out my sterring rack. Thanks for the advice, I will be contacting you again Im sure.

[goren420]

As I said at higher speeds vibrations would be more noticable if it were rotors, this could in turn make driving "difficult" depending on how you want to use that word. If they were visably worn when replacing pads then I could change them out and see if that helps... stock replacements aren't too expensive you can get them at local autoparts stores (Advances, Autozone, Etc.) Or you could go more of a performance route with drilled/slotted rotors to help cooling and warping issues... r1concepts.com has some good prices my roomate has their products on his explorer and loves them. (FYI if you do get rotors from R1concepts get the cheaper model (they have 2) I know this sounds odd but supposedly the higher end model has rust issues).

[goren420]

...and the steering rack, a shop can check it out easy... but if you have any play in your steering wheel (as in you can move it back and forth with no effect on your wheels) then it may be worn, there are a few rubber pieces that go bad after awhile, many places sell refurbished steering racks and work with core charges that you can get back if you send you worn stock one in to them after purchase...

[Zatrekaz]

Thanks a ton bro, Im gonna look into replacing the rotors. Even if that is not the issue I need new ones regardless. Gonna have a shop check out the steering rack for me soon. If that does not fix it I am gonna check into getting new Shocks before I get new tires. I need to lower the car anyways. Springs are cheap... it's just the shocks that kill the wallet.

[00BlueMustang]

What you could do is get some new rotors and go and see if you can turn the old rotors just so you have some spares just in case something crazy happens. That is what I did.

[goren420]

True it's always good to have back-ups, I keep all my stock parts that are in working order.

[00BlueMustang]

Originally Posted by goren420 True it's always good to have back-ups, I keep all my stock parts that are in working order.

Exactly, especially since it was only like $10 to turn the rotors. But Zatrekaz whenever you get everything fixed let us know

[justinsstang]

My rotors are bad on my car on the front... my car shakes alot sometimes. I'm calling it rotors on this one. I'm going to have to get mine fixed to, the steering wheel shakin is annoying as hell.

[poindexter18]

Also keep in mind that with bigger than factory tires and the consequential bigger rubber you usually have to have some what of a high performance tire. That'll make you feel the road more, and you'll catch ruts and shit that older and stock tires won't grab. But I agree with Goren about your mod list. If you want a better ride I'd look into some shocks and struts first. Or coilovers.