Suspension Upgrade Time - Installing QA1 Proma Star Double Adjustable Coilover + WCC Swaybars

My 4th track day out was a blast, but the upgrade to square 200tw tires was underwhelming. This seemed to be in no small part due to the very worn out 23 year old base model suspension on the C5 Corvette. I experienced a lot of body roll, and with the square setup the entire car seemed to be a bit tail happy with a penchant to understeer. Per researching, the solution seemed to be a superior spring rate along with better balanced sway bars. A lot of folks recommended going with the various improved corvette models transverse leaf springs and just upgrading the shocks, but it all seemed like money wasted on a half measure to me. This car is about the track more than anything, so it's time to pony up.

Being that it's the future, I'm a bit impatient about products showing up. I searched for coilovers and was seeing lead times of 6-12 weeks. I'm not terribly interested in what feels like loaning people money while they get around to building me my stuff, and so I searched high and low for in stock components. In the end I was able to find QA1 double adjustable coilovers from Summit Racing. I trust QA1, the spring rates all seemed reasonable, and there were a few aspects of the design I liked over other coilover designs I'd seen as well. There are likely some limitaitons, there are possibly some superior products out there, but there's no really exceptional exhaustive review of these products, so with the information I had and my willingness to wait, this seemed like the most reasonable choice. The double adjustability would let me dial my setup in as much as I likely will ever need to, along with bieng able to roll my setup back to being streetable hopefully.

Sway bars were also essential. There were lots of options out there, but the West Coast Corvettes Street/Race sway bars seemed like the best option out there for me. The price was good, especially considering I could get heim joint adjustable end links as part of the deal as well. The diameter and thickness of the materials used were identical to many other brands, and thus I decided to pull the trigger on these in the hopes I would reduce body roll and get some flatter handling around the turns along with hopefully some improved traction.

Takeaways from installation:

Right off the bat, I would recommend giving yourself two days for this process if you're doing it at home. I blitzed through this process in one day and as the day progressed onwards I got tired and started making mistakes that in the long run cost me more time. I would even go so far as to give yourself 3 days to install these, with the first day being spent just assembling the coilovers themselves.

Why QA1 or anyone else ships unassembled coilovers is beyond me. Faffing with the snap rings is endlessly annoying, even with my specific set of snap ring tools it was a nuisance. For the price of several thousand dollars it doesn't seem outlandish to assemble them.

One thing I recommend that unfortunately the instructions don't mention is just how much preload to put on the spring. I went halfway on mine right from the getgo, which if I recall was roughly 40mm from the preload adjuster to the bottom of the rebound knob. This gave me a pretty decent ride height right from the getgo to adjust. I had to make a few adjustments after the fact, but it was quite reasonable to do so just jacking the car up and squireling my hand up and around the suspension to where I need to reach.

Initial Street Impressions:

QA1 yet again underwhelmed me with some pretty shit ranges of settings for compression and rebound on installation. I wound up at the extremes of their recommended settings in the rear and different up front, which they did not call for in their absurdly wide range of baseline adjustments. To me they clearly didn't test this on enough Corvettes to have a solid baseline.

Speaking of adjusters, these are supposed to have 18 clicks of adjustment, but anything past 10 clicks feels like you're trying to break something. On more areas these suck.

I'm also underwhelmed by the entire lack of feedback from anybody in the Corvette track groups I'm in. I post up that I've got them, what are peoples settings... and crickets. Nobody is running these. QA1, if you want these to take off, you need to support these in more than the half assed fashion these are currently in.

My settings wound up 3 front and rear for compression (below their recommended street range) and 7 rebound front, 11 rebound rear. Using a 3/7 combo front and rear, the suspension would hit a bump, compress in the rear, and then rebound quickly, causing the rear to bounce. The rear would settle again, and come back up yet again, sometimes bouncing a third time. This created a jolting sensation. No idea why QA1 didn't differentiate the needs of the front and back. Somebody clearly got lazy on the job, shame on QA1.

Current Overall impressions: Cannot endorse coilovers.

I'll need to see how these handle on the track to be certain, but my initial take on these is that they're harsh, don't tune as advertised, and assembly is a pain in the ass. I can't say I'd recommend these products to anyone else. While these do not have high speed circuits, that doesn't mean these can't be valved to accomodate high speed compression and rebound needs, which I feel like these are not, hence on harsh bumps these are absolutely painful.

For average to even spirited street driving, I don't think these offer an improvement over OEM or the Z06 spring/shock combo.

As for track driving, I'll report back on more as I use them over a few days. I will also document my findings in a Google Sheet.