what to do with springs

Discussion in 'Race car chassis tech' started by agetnt9, Oct 4, 2013.

  1. agetnt9

    agetnt9 Agetnt9 (Dan)

    got a 72 GS 455 4 sp. want to know what to do about the front end slamming to the ground. Shocks springs control arms or what?
    dont want to bend the car and headers when i hook up!! Just dont know how some do wheel stands and not slam the car down.
     
  2. Briz

    Briz Founders Club Member

    Drag shocks should help.
     
  3. agetnt9

    agetnt9 Agetnt9 (Dan)

    Yes, and i think maybe a spring that gets stiffer as it is compressed:Do No:
     
  4. 54Rich

    54Rich Silver Level contributor

    I have a pair of 5536's in the for sale section, they were too stiff for my liking on my 69. I know a lot of people use them?
     
  5. Gary Bohannon

    Gary Bohannon Well-Known Member

    That 5536 spring has a load rate of 487 and should handle the load.
    * First get a stronger spring. (Stock GS or stiffer, like the one above)
    * Second stiffen the shocks.
    * Third put the stock swaybar back on the front to work as a rise limiter, then distribute the drop evenly on the front wheels.
     
  6. agetnt9

    agetnt9 Agetnt9 (Dan)

    Like 90-10 shocks, what kind? also the higher the # the stiffer the spring or not so? thanx
     
  7. Clanceman427

    Clanceman427 Hardtops need not apply

    Just curious: what is your 1st gear ratio, rear end ratio, and tire size? Given the fact that it's a 4 speed, the sky's the limit I guess with how hard you launch and hook. If you have a very steep final drive ratio for 1st gear and a short rear tire, you might be in a situation where the car (if it hooks well) will rise fast and subsequently run out of torque fast if you have that steep final 1st gear ratio, so you'll have to manage that with your driving. You could take gear out to make the launch less wheelstand and a little more wind out of 1st gear to keep it from slamming.

    As a comparison, my Monte has a TH400 with the 2.48 first gear, 4:88 rear gear, and 28.5" tall slicks. I leave off a transbrake at peak torque (roughly 500hp BBC) and the result is a short wheelstand that only lasts in 1st gear and the front end is down when I'm ready to hit 2nd, which is about 2 seconds or so into the run. I use Moroso drag springs for BBC G body application, 90/10 shocks (which means they extend very easily and are tough to compress vs. a 50/50 street shock), no sway bar, and I loosened and double-nutted the lower control arm bolts for less binding. Here is about the extent of the wheelstand:




    Have you run your car yet? Maybe just take it easy on your first couple launches and ease your way into feeling out how hard it launches and might put the front end in the air. Nothing can really protect your car from the hard landing if you stand it sky-high in the air and then let off, or run out of 1st gear torque too fast from having too much of a "granny gear" final 1st gear ratio.
     

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  8. agetnt9

    agetnt9 Agetnt9 (Dan)

    I have not run it yet. got 1973 fine M-21 2-20 first and 1.64 second with 3.73 12 bolt. 29" tires. i think i will start with 90-10 shocks,what kind i have no idea..:confused: and the Globle West DEL-a-LUM A arm bushings and see how it feels. Will keep U posted for the help brother.
    I am getting ready for the winter now and not much time for playing around.
     
  9. Gary Bohannon

    Gary Bohannon Well-Known Member

    The best 90/10 shock for the money is Calvert. Not expensive but well designed for cars slow and fast. ( Designed by the guy who built Caltrack traction bars). Some use these Calvert 90/10's for street use and say they are fine.
    Calvert's are fast to rise, but more firm when the front end drops. Cheap adjustable 90/10's are sloppy.

    The High-low numbers on springs: Part numbers mean nothing, Spring rates are the indicator along with the free hight, installed height and wire diameter, etc. Seek advice by the suspension gurus. You need a firm spring that will leave 40% of free movement to rise and 60% to catch the fall. A too tall spring will have you shoved up too high, and a shorty will leave little room to prevent bottoming the suspension.
    You only use tall/soft springs when the spring is used to boost the front end up faster or higher.
    A big powered car will pick any ridgid frontend with a tap on the throttle. You just need a safe way to get it down.
     
  10. sean Buick 76

    sean Buick 76 Buick Nut

    Swap the 350 back in, or by 455 springs...
     
  11. Gary Bohannon

    Gary Bohannon Well-Known Member

    Moroso racing springs fall a little shorter each day. Last about a year, if you don't break something first.
    A good Moog spring will last for many years and protect your car. Get a spring made with .625 diameter wire like GS factory springs, not the .609 Skylark, Special and 6cyl type.
     
  12. Todd69GS

    Todd69GS Silver Level contributor

    Gary is right about the Moroso springs. They will do the trick at first but they will quickly deteriorate. There's tons of stock springs that will work if you get the spring rate right for the weight of the car. Or you can measure where you want the front end to sit, weigh the front of the car and call a company like Santhuff. They will make you a set to your specs. As far as shocks go stay away from the el cheapo 90/10's if you drive on the street. Get something at least middle of the road.
     
  13. Buick-Fun

    Buick-Fun Well-Known Member

    QA1 coil over, double adjustable shocks. And fabricate a skid plate so if you happen to slam it down you won't hurt anything.
     
  14. agetnt9

    agetnt9 Agetnt9 (Dan)

  15. Gary Bohannon

    Gary Bohannon Well-Known Member

    Calverts, yes.
    A lot of fast chevy boys using these Calverts. Easy up, but real firm comming down. Good quality at a reasonable price.
    They say adjustables are junk except the mega $ ones.
     

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