First test drive of my QA-1 dual adjust Coil Over front end.
 

The weather finally broke into the 50's with all dry roads. So I threw on the front tires and hit it hard.

First day of test driving my new Wilwood front brakes and QA-1 Dual Adjust semi coil over front end. Before I removed my 550# front coil springs I measure the hieght of my wheel wells on the centerline of my front tires. I had 27 1/4 left front and 27 inches on the R-front. For racing QA-1 recommended their 450 pound spring. They also recommend starting with the spring being screwed up about 1/2 way.

Well just for ease of assembly I had both springs all the way down. When I mounted the front tires and dropped the car down the wheel well was over 28.5 inches. So I went out and roared around stomping on the brakes to settle the springs and when I stopped a remeasured it had come down to 27 1/4 on both sides. This is with my front street tires 255/45/17. I think that my front tires are right at 26 inches in diameter.

So I have to tear it all apart again. :( I just don't have enough front end weight to use that big of spring. The springs are already at the lowest adjustment so all I can do is lift the car, I can't lower the front end. So 450# would only be good for big blocks or cars with a stock front end. My racing front tires are 295/35/17 which are right at 25 inches in diameter. I would have way to much tire to wheel well clearance. My idea with the adjustable spring height was to be able to crank it down for track days and have the nose near the ground.


The problem here is I trusted QA-1. They have a phoney chart of spring weight vs front end weight. So when ever I talked to the dummies at Tech they they kept feeding me the party BS line. So I learned a lot since this was posted in 2008

Right Idea!
 

George: I'm in the same book, but not quite on the same page. I want to do something similar using VB&P Mono/Trans springs and Bil shocks.
I doubt that I will need the adj that you do. I want to set it up for a very neutral ride/handling and drop it for SSC.
All those adj would have me even more crazy than I already am.
First I have to see if I will have a job before I get crazy w/Vette.
Please keep us mortals posted on your progress.

Ricisan

This sounds a lot like the problems Cali,68,L-79 had with the SpeedDirect semi-coilovers. He was directed to cut coils and then it got to the point where the top of the spring was becoming unseated from the seat in the frame. Hope you have better luck.

Other than the height,how did the 450's compare to your old 550's?

I just ordered the QA-1 single adjustable front shocks and opted to keep my 550's. Ride height for me is perfect,and I love the pool table flat cornering.

As it sits, I think my front fender lip sits at just over 27 inches,and the tires are 26.6 (P245-60 15's)

I also have the 350# springs for my QA-1's So I'm going to throw them on. I really did like how flat my car would turn at the limits of my street tires. I also did notice any front end dive.

As I understand it cutting coils increases the spring # rate. I don't want the front end so over sprung that the tires don't follow rough pavement.


I'm going to call QA-1 and ask what my options are

yeah, keep us informed......i was looking into getting the qa1 coilover setup for my vette here in the next month or so........i've wondered how low those things would let us go. Kinda pointless to purchase them if you can drop it a decent amount ya know?

could we get some pics of how they're set up on the car? Do they just bolt in place of the shock at the upper control arm and then with the two bolts underneath the lower control arm?


thanks for the info!

ryan

I think that my front end is stiffer. Logic would tell you that pure math would be right. If it takes 550 pounds to compress one spring one inch and only 450# on the other. So I think that QA-1 shock on a 5 and 5 setting is vastly superior to my previous KBY gas shocks. The other thing is..... how much do 550# spring get softer with age and use? I'm glad to know that 27 inches is in the correct ball park.

bluegtp I called QA-1 and he recommended going with my 350# to get the adjustment back. But when I brought up road racing he said that cutting out one turn would give me one full inch of adjustment . Which translates out to @ 1.5 inches of drop on the wheel well.

The QA-1 bolt on top of the A-Arm. You have to drill out the existing holes to 3/8th to install nylock grade 8 bolts

You can also see my QA-1 dual adjust coil over fronts that I installed.

I bought the 13 inch kit from Kieth at Corvette Engineering. I shopped around and definitely Corvette Engineering had the best deal in town. I did learn allot about brakes shopping around and talking to people.

These are the two piece Wilwood 13 inch rotors with Superlite 4 piston calipers. I got the optional $300 Thermloc pistons and the $200 "J" pads.

The kit was a no hassle installation. Just take it apart and install the new steel braided lines and Keith’s quality steel mounts.

The video starts on filming the passenger side - look at the big beefy pads!

http://s124.photobucket.com/albums/p...WoodBrakes.flv

I'm not sure these 550 lbs springs have lost a bit of rate over the ten years on the car. I did not record the height at the time I installed them,but it was in line with what VB&P said,in that it dropped about 3/4 inch to one inch from stock. Car is up in the air now waiting on tie rods and the QA-1's,so I can't re measure right now.

I'm just going for the one coil cut and mild heat the spring top to recourve.

I just thought about something that occurred a couple of years ago on the road racing track. I had the one inch shorter 550# and 1 1/8 sway. Our local track has some very rough high speed transition braking. I compression blew out a stock length KYB gas adjust shock from summit racing or Vette Brakes and Products. I then bought a shorter front shock that never bottomed out.

I also do not have the rubber stoppers that limit suspension compression. Added weight + you never want your suspension to go hard all the sudden during a max "G" turn

1" shorter 550 spring...... because you cutted a part of ?

As you know, cutting a spring, you are incresing it's ratio in a linear way:
If the spring have 10 coils an you cut away one, the result is a 10% increase in ratio..... due to the fact that you are reducing the lenght of the steel wire.

The risk is to go over the tensile limit of the steel if the spring isn't of a very good quality!

If the srping was born allready shorter..... ok!

the VB&P 550# and 460# are sold one inch shorter than the ride height of stock new springs.

I am also considering pulling off the lower A-arms and then cutting out the center and rewelding up the shock lower mount point one inch lower

But..... no one producing drop-spindles for Corvettes?:ack:

That is similar to how I kept my shocks from bottoming. I don't have coil overs on mine, its just lowered with standard shocks.

I put studs in the a-arms, fabricated some spacers from thickwall steel tubing, and bolted the shocks on ~1" lower. Works great.

My QA-1's should be here for the weekend. This shock bottoming out issue has my interest. Is this due to the shock being too long for the application,or the springs being too soft. I haven't pulled the old shocks yet,and will check for evidence of bottoming out when I do pull them.

In my case I baught the single adjustable non coil over version,so I'm thinking of just mounting the bottom shock mount to the underside of the control arm. I also still have the control arm bump stops still on the car.This would make the install easier,and also reduce the risk of bottoming the shock by a little.

Any thoughts?

I managed to blow out a KBY gas adjust on the race track with front 550# from bottoming out. I don't think that you could do it on the street unless you hit something.

The QA-1 shock body is so big of diameter that you are not going to fit it through the a-arm hole. Also mounting it on the top or the bottom is only a change of less than 1/4 inch

In my case, its because I lowered the car quite a bit to obtain the best suspension geometry for handling and to improve stability at higher speeds. The shock shouldn't bottom on a stock hieght car with the factory bump stops.

I lowered the bottom end of the shock to get it back closer to its designed operating range.

Got the QA-1's late today,and a quick peek looks like only minor clearancing of the lower control arm to pass the shock adjusting knob through,and they should bolt right up.

On the bench they have a huge range of adjustment from what I can tell by cycling the shock by hand. I think I'm with you on a base line of 5 for starters.At the lowest setting they feel like 10/90 drag shocks.This could be fun at the lights.:thumbs:

Interesting thread hope this all works. I have 800 lb springs and custom built Koni single adjustable shocks in front. When running 295/35/17 Hoosier A-6's keep the shocks at full hard using a 1 1/8 sway bar. If your are running the harder R compound tires the softer springs should work. My front bump pads are virgins, did need to shorten the rears though.

http://www.finitesite.com/markwallas/QA1b.jpg
Minor filing to clear the adjustment knob was all that was required to install the QA1 TC1959P front shocks if anyone's interested.I used the stock lower bolts for now,but will at a later time replace them with the heavier bolts that came with the QA1's

A battery,and front end alignment is all that's left to do.:thumbs: