I use the QA1 semi-coil overs on the front with the 350# spring with a stroker BB with aluminum heads. I have 255/50/17s on all four corners. I built a horizontal system with QA1 double adjustable coil-overs for the rear and I have 16,000 miles on them. I use it mainly as a daily driver with the occasional trip to the drag strip. If I were going to race it regularly on a road course track, I would go with the full coil-over conversion for the front. Just don't believe the semi-coil overs to be as durable although mine shows no signs of wear and I too doubted the lower shock mount bolts ability to hold up.

 

The QA-1's mount above the lower A-arm and come with 3/8th bolt kit that you have to enlarge the bolt holes.

I have a front end that I took 300 pounds off and with a small block and I installed the 450#

 

Its a C6Z but still a really neat video and gives you an idea of how the full coilover and suspension generally works together.

http://youtube.com/watch?v=Q9YGAS4Ave4

Makes me want brake cooling ducts...imageine that rotor without them

 

How can those two tabs on the lower a-arm that the shock bolts to be strong enough to survive the weight of the car in this design, or am I missing something?

 

Aren't the lower shock nuts welded to the same plate that carries the spring in the stock configuration? If so, I'd imagine that the metal is plenty strong.

 

Full coilover is the way to go. That's the first thing I saw that I didn't like.

 

There's a big difference, the stock design transfers only the shocks dampening forces to the lower a-arm, this new design transfers that and the car's weight through those two tabs, unless I'm not understanding something. I can't tell from the photos but maybe those tabs are actually boxed in with metal underneath.

Van Steel, what am I missing?

 

The spring will carry only the load......

The shock is adsorbing the acceleration!!!!!
Remember that a normal bump in the road can exced 1g of acceleration.... and a bad hole in the road can reach 2-3g of acceleration.

1g = weight of the car
3g = 3 times the weight of the car!!!!!!

Don't be afraid of putting the whole coiolver in the shock mount!

Nobody is concerning about the shock bracket stiffness when is replacing stock shocks with much stiffer Bilsteins or Koni or QA1..... but the load is increasing several times!!!!!!

 

I'm concerned about all loads of the front end, static or dynamic, being transmitted through those two small tabs welded to the lower a-arm that the bottom of the shock/spring combination bolt to, it looks structurally weak to me. The stock suspension transmits the weight of the car to the lower a-arm with a huge spring pocket formed as part of the lower a-arm.

 

The 2 shock mount nuts get removed or drilled out. Thats it. The arm is plenty strong. The t-bar on the bottom of the shock is designed to hold the load. It's a metal t-bar not aluminum. Most of the late model GM kits bolt on the same way except they are heavier cars. I run them on my 70 Monte Carlo and we all know how heavy those things are. If your worried about the integrity of the arm and want to run these, you can fab up a plate and weld it in the pocket of the a-arm or go with tubular lower a-arms. I don't for see any problems unless your arms are in ruff shape.( ie, very pitted, very rusted) I have had no complants about it not doing it's job or blowing through an a-arm.

 

What I was referring to is the shock mount of the lower full coil over a-arms, please refer to the two red squares in the picture.

 

OK..... sorry!

Anyway, for my opinion, a tab like that can hold tons of load.... the force is axial with the tab.... and if it is made with good steel... no problem!

 

OH My bad. I thought you were talking about the semi-coilovers and a-arms. All parts are made of chromoly and can handle the load w/no problem as stroker427 mentioned.

 

How much is that kit on the picture for a 77?

I was thinking of going with single leaf spring in the front and get rid of the coil springs...plus it saves wait.

This set up looks even lighter given it replace upper and lower A arms...

Both have to be lighter and a lil better then stock?

thx
r

 

I have to DISAGREE on running stock control arms with the QA-1 style "semi-coilovers". You are asking a lot of the metal stamping that was originally designed to asorb loads from a shock asorber ONLY! I would never install this kit without adding some strength to the lower control arm. To give everyne a little "history" on the quality engineering QA-1 did with this kit, originally they had people mounting these kits below the A-arm with the 5/16" bolts, after several failures, they changed the directions to mounting them above the A-arm, this only buys you a little more time before failure. You SHOULD weld in a support plate if you intend to run this set-up if you drive you car long distances or run it at the racetrack. I also have some concerns about the lower mounting shaft that has 2 grooves machined into it for retaining rings to keep the shock centered on the mounting shaft (looks like a invatation for failure in my mind.) The lower shaft has a BIG job in supporting the weight of the front of your Vette (at least 900LBS per side of static weight.) I have one of these kits for a project Vette right now, the car is waiting for me to fabricates some better mounts for the lower shock location, I intend to use a AN type airframe bolt of 1/2" diameter and make a lower mount with spacers to keep the shock centered. QA-1 could help its customers greatly by providing a circular plate of 1/8" thickness or better to sit down into the spring pocket and help spread the load around the surface of the lower A-arm. My opinion, if your running this set-up without support, your on "borrowed time" and headed for DISASTER! I have expirienced a lower ball joint failure ona POS work truck while travelling down a city street at 30MPH, I "saved" the truck, if I were in a Vette at high speed and had the suspension unload due to the lower mount failing, I'm not sure you could "save" your Vette from crashing. When that mount fails, your tire is going to BANG into your fender (destroying your body) and possibly lock-up your steering, not a chance I would want to take in my Vette.

 

Solid LT, If I use kit pictured above which replaces all for arms does that spread or is better able to handle the stresses your talking about?

I will go with the single mono spring if this needs alot of fabercation work. I can bolt on part but i down own a welder or have the ability to cut steel etc....

thx
rich

 

I installed my front tubular A arms and coil overs today. I had to clearance 3/4" from my spring pockets and really should have taken off just over an inch to be on the safe side. I don't have anything on my frame right now so there is no weight to keep the top arm off of the bump stop. The only problem is that the arms have a tube that the bump stop hits into and because its round the stop distorts and kinda slides round it. It looks like I'm going to have to make up a different stop which isn't a big deal but would have been nice to know before I had everything together
I cant give any driving info but they seem nice. Cutting out the spring pocket was a little setback but wasn't too bad. On the whole they seem nice and look pretty cool

 

So has anyone completed this rear kit, and if so whats the outcome?

 

Here is the front QA-1 dual adjust semi - coil overs 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

 

nobody has done this????