im look for some rear drag shocks and they have different ratios...50/50...70/30...wat do these numbers really mean? it has to do with collapse and rebound right? im trying to get the most weight to the back...the most crunch. which ratio should i go with?

 

have you already replaced the front?

 

you should do 90/10s up front and 50/50s put back. Try to get adjustable ones, strange makes adjustable shocks, i was guuna order them for my mustang but never did.

 

Rear shock settings depend on how your suspension reacts. As mentioned above, 50/50 is a good starting point. The best suspension setup has zero anti-squat. That means the diff won't rise or drop in relation to the body when you launch. If the tires hit too hard, you take away anti-squat which allows the diff to move up into the body or what you see is the body dropping down as you launch. If the tires don't hit hard enough, you add anti-squat by changing the IC (if possible) which will drive the tires harder into the ground and the body will separate from the diff or rise up on launch.

Each of these situations require a different shock setting. All the springs do is support the weight of the vehicle. The shocks control how that weight is used. You want the tires to stay planted as long as possible without bogging the engine down. If you get a lot of anti-squat and the body moves upward which is forcing the diff down, you want the shocks to extend easily but slow to compress. If the tires unload from loss of traction, you get wheel spin. If the tires hit too hard, you get tire shake.

Adjustable shocks are a tuning aid. There is no magic setting. Each vehicle reacts differently to different track conditions. A setting that works well on one car will probably not be what you need on your car. Adjustable shocks are still better than OEM shocks but you need to try different adjustments to see what they do under different track conditions.

Single adjustable shocks typically control the compression or a combination of compression and extension. They're inexpensive and for the most part, will do the job required. A double adjustable costs more but allows you to control the compression and extension separately to fine tune the shock setting.

The first number is extension. The second number is compression. 90/10 means the shock will extend easily and take longer to compress. 70/30 means it won't extend as quickly and will compress quicker than a 90/10. 50/50 means it extends and compresses at the same speed.

I use a 12 way single adjustable on the rear of my car. I currently have them set at 5 clicks from full soft and may need to go a little stiffer. On the front, I use Koni SPA1 struts. On full soft, I can grab the front of the car and bounce it up and down. If I stiffen up the adjustment, it's very hard to pull up on the car.

On the track with a full soft adjustment, I can easily pull the wheels when I launch however when the nose comes back down, the front end bounces which causes the rear tires to unload. By stiffening the front shock setting, the front comes up slower and when it comes back down, it doesn't bounce as much and I get better traction.

 

this article helped me with my cars http://www.baselinesuspensions.com/i...A_Drag_Car.htm

 

imo id just use stock shocks unless your having a traction issue.

i was layin down consistant 13.5's on stock shocks with a 3.73 posi. got more wheelspin out of my second gear scratch

 

Stephen, that was a very nice and tourough post, but if I can pick your brain just a little more, what exactly is tire shake?

 

Tire shake is when the tire face sticks to the track so tight that the sidewall flexes and wads-up causing the tire to be stretched out of shape whereby the tire runs over itself.

 

OK, that must be what my car does then, I hook well initially, then after about 5 to 10 feet , when the nose drops, my sidewalls wrinkle and I lose traction. Is this because I hit the tires to hard? On a launch my rear stays pretty nuetral, if it does anything it raises slightly, and my front end lifts pretty drasticly.

 

bart i like ur 4.10 ticking time bomb i promise they are we broke a set in our stock rear this year.