Eibach ERS 60mm ID x 60mm ID Helper Spring

I bought Silvers Neomax coilovers with aero spring rates (14k/12k) for my track car. The quality of them is great. Install was straight forward and they are easy to adjust and tune as needed. Real happy with them so far and I think they're the best value out there in coilovers. Great price without a sacrifice in quality or performance. Also Brian at FI PERFORMANCE has been great in responding to all of my questions. Has been a great experience so far.

Quality part.

Brian answered every time I called and answered all the questions

Excellent coilovers
The best customer service from Brian
Highly recommended
Car looks great and. Handles amazing

Works great it stiffens up the rear end and no more wheel hop best diff brace out of all I have used in the past, money well spent.

Installed the After Dark hooks on my C5: the rear hook was very easy, and if you only need one hook, it's a quick and easy install. Front is more work: you're going to want a step drill or right angle adapter, since clearance between the bumper and A/C condenser is tight. Drilling into the bumper is not trivial: it's hard, use cutting fluid and make sure your drill bits are sharp. Once it's drilled and the rivnuts are installed, it's easy from there. It's a good design, well made, and at a reasonable price.

The product was originally marked for 2005 and up gx470. I managed to fit it into my 2003 by flipping one of the front hanger mounts. Sound is throaty and deep a bit loud at first. But the sound has mellowed out after a few hundred miles. Hardest part was removing old exhaust had to use Sawzall. Make sure to buy the 2.5 donut gasket ahead of time. The system is high clearance. Its tucked between the frames no chance of hang ups.

It’s the best mod I’ve done. Should have been the first thing I did.

Brian was extremely kind and helpful to make sure I was getting set up with the correct products. The Brey Krause harness bar is extremely high quality. Don’t cheap out on safety stuff this is definitely the harness bar you want in your c5. The combination of great service from Brian and the quick arrival I highly recommend FI Performance and will definitely be using them in the future!

Five stars for the parts and service. Ride quality is better than expected for a coilover setup. And Brian was super helpful in getting the correct setup for my truck

Fits perfectly and does exactly what it needs to do. No complaints.

Brian recommended these end links after sharing my plans to do some HPDE, Autocross and Street driving for the C5 Z06. The parts feel great, I did have a warranty issue that was addressed by both Brian and AFE, I was very satisfied that they took care of my issue in a timely manner as well. Highly recommend both Brian and AFE, thank you as always for your help!

Brian definitely knows his stuff, he recommended these after asking what my plans were for the car. This is a huge upgrade to my C5 Z06 and the ride quality is tight and feels great!

Came packaged well, looks great fit as it should. Much better than other cabon hoods I have bought in the past. Brian's customer service and willingness to assist is second to none!

I purchased a kit from Brian with Swift springs. I must say that the quality, fitment and easy install was awesome.
Beeing a racercar driver I have dealt with many sorts of coil over kits. I have also attended to several car/racecar projects. So my experience with coil over systems is wide. Like Reigers from wrc, Øhlins, Team Dynamics etc etc..
The installation is easy but use time to do things properly.
Very lightweight but also seems very well built dampers.
It is easy to adjust height and stiffness. But I will recommend to do this very carefully and with some patience.
Brian is a very nice guy and very fast to answear questions. So thumbs up for him.
All in all I would highly recommend this product. My Z06 did get a much better grip and feel in corners and the car became perfect on bumpy tarmac roads.
No need to scroll the internet for several different brands. This is a great value for the money to any use of your car.
Thanks again Brian for great service and a great product.