Custom Built Front Drag Coil Overs

392Bird

Registered User
I have been working on getting these built for some time now. These are custom built QA1 Pro Drag Shocks for MN12s. I just got them yesterday, and will install them in the next couple of days. These are Prototype now, but as soon as tested and any changes needed, they will be available. They were built by a QA1 dealer, not the QA1 shop it self. I will update as I progress. These are 90/10, set up as fixed Compression, and fully adjustable Damping, (extension). These alone take off about 20 lbs from the front.

MN12-QA1Pro-drag-coilovers1.jpg


Lower part:

MN12-QA1Pro-drag-coilovers2.jpg


These are still Prototype, and no firm price has been set.
They mount to the lower control arm the same as the stock ones do, and mount to the stock top piece, that has the 3 studs on it, as the factory ones do.
 
Hey Bruce! Nice job!!!!!!! :eek: :eek:
You need to contact Randy because I think he was wanting some of those.
Put this thread in the new parts section. I think you might have a hit on your hands. :)
 
I would be interested in this setup if you could get them in a 70/30 setting for the street strip guys and there would be a bigger demand as well. It would be great to get QA1 to do a shock shock for the rear too.

Zack
 
These are done as a prototype, and when it is determined that they are correct, and if there is decent interest shown, they will be made available to your specs. Once the fronts are done, we can start on the rears. My Bird weighs less than 3200 lbs, so when done, will have them determine what is needed for the different weights, strip only and street/strip use.
 
A few pictures taken today during the install.

The coil over with the stock top piece installed, ready to go.

qa1feb21-2.jpg


Mounted up to the shock tower from the bottom

qa1feb21-9.jpg


View from the top

qa1feb21-8.jpg


View of the bottom mount, 12 position adjuster knob and heigth adjustment ring

qa1feb21-12.jpg


Over all view installed

qa1feb21-14.jpg


I have a few thing to get changed, then they should be ready to make them as needed.

Example: Will advise them to do these with the adjuster knob to the rear. This will protect it, and allow easy adjustment by just turning the wheel and reaching in. Ideal for between round changes at the strip.

A few other minor things.
 
With the range of available adjustment, with a fixed compression and adjustable rebound, it would seem obvious that the 90/10 would apply to a full soft setting. Full firm would be something else 50/50 perhaps?? What is the range?
 
PLEASE!! keep us posted on these shocks. Those are what I have been dreaming of. With a manual steering and Mustang hubs with skinny tires real race car. Thats what Iam talking about. Thanks for you work on these! :)
 
Dave: Bo idea on what they will go from-Too. I did the test install today, and need to do a few other things before they go on for good. Also the springs I am using are only to get a eough idea on the fir. They will come back off, and go over to my buddys shop as soon as he is back from Daytona. He has a full race shop, and I will put these on his shock dyno, and get data. I need to get it 4 corner weighed also, then will decide on what springs it will get for the strip, most likely in the 175-200 lb range. They can valve these any way you want. I told him when in the lowest setting, I wanted to be able to pull the tops out with one hand, and wanted the compression stiff enough that if the car was off the ground and set down, it would take 3-4 seconds to settle the shocks :) Ill see on the dyno how close he got.

Oh, and once all the little details are worked out, they will make these up for any type drivivg, and adjustable or not.

I will keep everyone up to date. I hope to have this completed, and ready for our local strip to reopen Mid March.
 
392bird
Is it possible to get the front coilovers NOW.I have been getting parts
together to finish my 4130 k-member.I plan to swap my
k-members again in the next couple weeks.If I get all the parts
made & assembeled on my new K-Member.Road race shock valveing
is the shock set-up I like to have.

Maybe you can help me with these's parts .I am wanting
to machine or buy,Aluminum hubs,and aluminum brake carrires
with bolt-on disc brake rotors.

I hope to take close to 100 pounds off the front. With the
use of a 4130 AJE K-Member with my lower control arm,
plus aluminum hubs,brake carrier,aluminum adj coil over shocks.
And some left over H.D. parts.

I would be interrested in buying a front pair NOW.If you
want to sell any.

I am interrested in rears also. :)

Thanks Randy
 
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I will be out of town today, and need to get a couple of small things sorted out tomorrow on these. I hope to have everything worked out, and final install next week. If so, will pass on all information to the shop and here.

Randy, you sure those pieces for the HD are not oil soaked? :)) JK

You need to get Pet Hill to be your partner, then you would be sure to lead the pack :)


Bruce
 
I commented over on TCCoA about this, and I will comment here. I am very concerned about the manner in which these coilovers load the stock upper mount. You are applying a large force to an area that wasn't originally designed to withstand that much load. You are basically point loading the center of that mount. Originally the outside of that mount was designed to carry the load transferred via the springs, but now you are changing that drastically. I think go to with this you need a new upper mount as well, whether it be via a rod end type connection or a bushing type. By the way, I would guess those were built using C5 Corvette rear shock parts right?

John
 
John there is no design change for the front of mn12 birds.
They all ready have coil over shocks on the front.
But they are not aluminum and adjustable.And no-one makes
a adjustable aluminum shock with the poper bottom mounting.

Some work may be needed for rear adjustable coil over shock
installation.

Randy
 
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Yes...there is a MAJOR design change...In the stock configuration, a 5" spring sits in the spring seat molded into the upper mount. This seat is backed by a metal plate in both the mount and the shock tower. That is the load path to the chassis. In this design however, the load path is through the center of the mount where the stock shock rod passes through normally. This is a MAJOR change from how that mount was designed to be used. There is no steel plates there to reinforce it. You are changine from a very distributed load to a very concentrated load. This will eventually lead to a failure in the upper mount.

John
 
Maybe I am missing something.Bruce is using the stock steel shock
mount,On top of his QA1 aluminum adjustable shock.Would'nt this
spead the load the same as the loading was with the stock
coil-over shock in the shock tower.

Thanks Randy
 
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No, it isn't the same...that's my point. The way that these are setup, only about a 1" diameter portion of the stock mount in the very center is trying to absorb the entire load from the front suspension. Plus, there is no steel to support the mount in that location, only molded rubber. In the stock configuration, the load is distributed in a 5" diameter circle which is backed by the steel in the mount, and the steel in the shock tower.

John
 
By the way...maybe this will help to explain it a little better. The center of the stock mount is NOT steel. The center (2"+ in diameter) is rubber only, and this is where the entire load is transmitted.

John
 
I take it this occurs because the new spring is a smaller diameter than the stock spring?

Are the pieces you are having machined sit on the smaller spring and then transfer the load to the original metal support on top?
 
Yes, that is exactly the problem. In fact, this is accentuated even more because the upper spring seat on the coilover is slightly conical in shape. That further concentrates the load from like a 2.5" diameter area down to like a 1" diameter area.

The parts I am having machined?? Which parts are these that you speak of? I have a set of these in the works for myself, though I am doing them quite differently. I am not planning on useing the stock upper mount whatsoever.

John
 
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