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Discussion Starter · #1 ·
I'm going to be installing QA1 double adjustable drag shocks front and rear. This will be my first attempt at some suspension tuning.

Any one with experience using these chime in. I could use some ballpark settings for street and strip. I'm not going to have much track time to set them up, before the "event".

TIA
 

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Looks like no one has tried to help so here is what I have seen. The weight of your car and where that weight is placed, front/back percents, play into what works as well as track conditions.

Try setting them at 2 or almost all the way soft in the front and rear. If you get too much bounce in the front then slowly adjust the front harder. In the rear if the body trys to seperate too much then go harder. Don't go past 4 or 5 in the rear as the higher settings are for road racing and are too hard from drag cars.

You just have to play with it but start soft and work your way up.
 

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Beyond what Jeff said....

it'll depend ENTIRELY on how those shocks are actually valved. My experience with the QA1s is that the knobs, well, they change the ride but necessarily aren't valved the best for handling ;) (I'll just say I have a set of off-the-shelf Bilstein 1104/0929s on my car right now). Might be different for drag racing...hope it is!

Some general stuff :

Front Rebound : fairly soft, as you DO want the front of the car to be able to come up quickly on launch (helps weight transfer and rear tire "bite"). I'd start at pretty close to full soft

Front Compression : Lot more than the rebound...you DON'T want the front end to slam back down as this will unload the rear tires.

Rear Compression : likely THE key one (along with front rebound)...want enough that the tire gets a good "bite" but not so much that it overloads the tire on launch (and blows it off). I'd experiment more with this setting (noting that "ideal" may not be the same on each side) than the others.

Rear Rebound : As long as you are damped ok on rear compression, this one won't matter so much for drag racing.

Doubt I'll ever do it on my SS (unless I win the lotto cwm4 ) but it'd be interesting to throw something like a well-valved set of triple-adjustable Motons or Penskes at the car (I'd likely go Penske just because one of the valving experts for those happens to be local). Downside is cost : figure a couple grand PER CORNER :eek: . Upside is the adjustability (if you know how to use it) can work wonders both on the strip as well as the street and handling apps (road course/autocross)
 

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Discussion Starter · #4 ·
Thanks for the imput guys. I may have bitten of more than I can chew, with the double adjustables. I've been reading about the bump and the rebound. Just not sinking in too much yet.

I knew with the singles it's just pretty much hit and miss. Loose in front, and stiffer in the rear.

With the doubles, I've got 24 different adjustments, compression and rebound. They come set all the way "loose", I guess, is what you would call it.

All I wanted was a little better weight transfer.:) I've got tons of adjustability, but not much intelligence, right now!:p

Maybe I'll wait until I'm a little smarter to put them on. That could be awhile, though.:D
 

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Ed's suggestions sound like they should work. I played with the single adjustable QA1s on my SS a bunch and it seemed to get better times with all 4 corners set on the stiff side. With the fronts set toward soft, the nose would pop up quickly, but then it would drop down too quick and unload the rear tires. When they were tightened up, it would still go up pretty quick, but would be a lot more controlled going down. But then again, your car is making a lot more power than mine did. :D

The best way to figure them out would be to do lots and lots of test launches! :D I'm sure you can find a good stretch of road that isn't traveled much by others. ;)

I'm wondering how difficult it will be to adjust the fronts with them on the car. With the stock stamped A-arms and only 1 knob to turn, there wasn't much room. I would imagine it being worse with 2 knobs.
 

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Discussion Starter · #6 ·
Well, I was hoping for some input from somebody that used them on their setup. I may have to wait awhile to put them on. I probably won't get to the track, maybe once, before Atlanta.

I'm running the stiffer Bilsteins, already. With Cheston's logic though, I might not need them. If I set them all on stiff, wouldn't be much better than what's on there now.:D


But then, I'll be the first one to admit I know nothing about setting up shocks or suspension.:p
 

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Each car is different. My bolt-ons only car didn't have enough power to keep the nose up (transferring weight to the rear tires) after a hard launch but I would hope that your big motor is.

The car did seem to like the rear shocks to be set softer. I also had airbags in both stock rear coils and no swaybars.

Each car is different.
 

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Bob : a way to conceptually think about dampening...

Compression dampening : how much the shock resists being compressed (i.e. how hard is it to push in the shock shaft)

Rebound dampening : how much the shock resists extending (i.e. how hard is it to pull out the shock shaft)

The trickiness (and expense...and where QA1 falls flat not to mention just about anything that anyone I know of is running on these cars, myself included on my Impala SS) for handling applications is that you want the shock to act differently under HIGH speed compression events (i.e. crappy pavement, where the car "jumps" over bumps) and LOW speed compression events (i.e. into a turn, where the car will bite in over a large fraction of a second to multiple seconds).

"Cheap" shocks tend to be set up so they are too damped/stiff under the high speed stuff in order to get the low speed stuff close to right. Goto the high $$$ shocks and you can get it so the shock will NOT be that stiff on the sharp bumps but DOES immediately get (appropriately) more damped on the lower speed shock compression.

For our autocross car (a small 1989 Honda Civic Si with stiff springs in it) we went to one of the better shock setups this year (not VERY high $$$, but rather custom valved double adjustable Konis at roughly $500/corner). The car immediately got EASIER to drive (and the street ride IMPROVED) because the car dealt with sharp bumps a lot better. And we are on surprisingly "soft" settings all around on the shocks ;)

Note that GM is trying to get something like this with that trick "magnetic shock fluid" deal available on the Corvette and (I think) some Caddy models. I suspect that if you had the ability to reprogram the shock valving (i.e. tweak the software in whatever computer is controlling it) that you could do some really cool/interesting things with the car (for starters, think a setup that optimizes quarter mile launch)
 

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Note that GM is trying to get something like this with that trick "magnetic shock fluid" deal available on the Corvette and (I think) some Caddy models. I suspect that if you had the ability to reprogram the shock valving (i.e. tweak the software in whatever computer is controlling it) that you could do some really cool/interesting things with the car (for starters, think a setup that optimizes quarter mile launch)
Ed, GM has already done that in their Performance Traction Management and Launch Control. Ferrari also uses a version of this system.
 

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Discussion Starter · #10 ·
Thanks for the imput Ed. I guess nobody on this board has tried the double adjustables. For time concerns, I wanted some settings that would be close to what I have.

I'll tweak them, then, I'll keep it to myself.:D

Cheston, you added nothing to this thread.
 

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Bob good luck.

You should listen to Cheston, he's pre-law you know!
 

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Discussion Starter · #13 ·
It's not like I haven't been thinking about this for several years. I've read some of Chris Alston's stuff, and I think I have a good handle on what I want on the fronts, just not as sure on the rear.

I just figured somebody on here had got this down, and I could use some of their empirical data, to get me up and running.:)
 

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It's not like I haven't been thinking about this for several years. I've read some of Chris Alston's stuff, and I think I have a good handle on what I want on the fronts, just not as sure on the rear.

I just figured somebody on here had got this down, and I could use some of their empirical data, to get me up and running.:)

Any good 50/50 Shock, set of Airbags and you are good to go.

For a race only mod..
9C1's had a Pinion Snubber
Glue wood or rubber bumper to the axle housing to reduce the distance.
Make sure there is an inch or more clearance.
(which is also a sanction rule)

Again this is a race only mod.
Common in Stock Eliminator.

D
 

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I agree each car is different and the more power you have the more the nose is not going to drop on you. If your car already launches level the less difference you will need from one side to the other on shock settings in the rear. Basicly the better the chassis the less you're going to need a side to side difference.

I think those shocks you have were set all the way soft from the manufacture for a reason. I agree you may what to nose the fronts up some on compression to make sure the front would not drop too fast is you lost power on our heavy cars.

start soft is the best I can lead you and they shipped exactly set soft.
 

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rear shock settings will be different for slick/radial tire setups. what do you plan to race with? for a slick tired car,ive seen they like somewhere close to "middle" settings for extension and a little looser compression. a radial will need a softer extension to initially plant the tire and tight compression to hold it there.
 
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