Before install of the following had no problem.

Professionally installed the following
Eibach Pro Kit Springs
H&R 15mm Spacers/studs in front
18" Falken Torque 5 Wheels/Falken Azenis ST115 Tires

I get a terrible amount of vibration when approaching the speed of about 55 or 60 and it continues through higher speed.

Here is what I have had done so far.....All done professionally.

- Wheel Alignment
- Wheel Balancing
- Visual Inspections

After all of this I still get the vibration.

What can it be and how can it be fixed?
PLEASE HELP!

 

First red flag that pops up for me is the 15mm spacers. Are they hub centric? Were they made specifically for an EVO? Do the lugs have the proper seat to tighten the wheel down properly? Bet its the wheel hardware.

Check this out as well Vibration Diagnosis Flow Chart It may help

 

My dad just had problems with his 3000gt with bad tire mounting and balancing. Whomever did your work, take your car back and tell them to re-mount and balance everything. That will rule that out if you're still having problems.

 

they came mounted and balanced from wheeldiscount.com
Then I had them rebalanced, not remounted. But when they where rebalanced they even changed to different weights and didn't notice anything wrong with the mounting.

 

They are brand new H&R DRS series 15mm wheel spacers
It appears that they are Hub Centric as listed on their website
and they came with new longer studs

 

What Neal is saying is correct. Did you get NEW longer lug nuts. It may be that the lug nuts you're using (stock ones?) are too short and DO NOT seat properly thus causing vibration at higher speeds. If that is the case DO NOT drive your car as the wheels can come off.

 

The wheels sit OK on the lugs. The studs had to be longer to compensate the extra length of the spacer. It reaches and secures the wheel just fine.

 

Oh yeah I did get new lugs too
They are defenitely locking in and down tightly

 

My friend had a vibration problem running custom spacer on his EVO. They were also hub-centric.

 

Did he ever resolve the problem?
I am considering new wheels if this is the case

 

I know you said you put new wheels and spacers on but maybe your rotors are just warped. Mine started with a vibration at that speed and after about 2 weeks the wheel vibrated whenever I braked. I had my tires balanced and there still was a vibration. I brought it in to Mitsu to check the rotors and the rotors were warped. Have Mitsu or any shop check your rotors. It is pretty cheap to get them turned if that is the problem. This is just an idea if nothing else works. Good luck!

 

Defenitely not rotors. It feels like a bad wheel balance. There is actually no vibration at all when braking. I'm 100 percent positive its not rotors. I think it has something to do with the spacers. If this means anything, at high speed going straight you always get the vibration. When driving at the same speed and turning the wheel slightly to the right it smoothes out a bit. However making the move with the wheel gives a little bit of a blurp before soothing out. Almost like something in one of the wheels is moving......Hence why I think it may be a spacer. I have a feeling that it has something to do with either the spacers or balancing on the front. I hace an alignment done but I can't imagine it being that.[/

 

Did you check to see how well the spacer fit the back of the wheel? If there's play then most likely the wheel isn't centered exactly. Let us know what you find.