HDK coil over system - spring selection

Buschi340 said
for stock K-Member. Have it already and also the qa1 shock multiple adjustable.

My question is about selectiong the correct spring. I know I have too weight the car. The whole car or just the front?
From that Point i can follow the qa1 instructions and calculate the rate with weight and angle...

But - can I have a longer length than the 12" Shocks to give more travel in expanding for weight Transfer ( drag race some times ). regular spring just longer or high travel spring? Hope that doesn't effect streetability too much?

what about springs with multiple spring rates they offer? any good or not recomendable?

car is a 72dart with 6.1 HEMI

Coil-Over Springs | Street Performance, Drag Racing & Circle Track Racing Coil Springs | QA1 Suspension

I dont have kit you do but I do have coil overs. I've got a big block up front so I'm running 375 lbs front springs and 200s in the rear. To accurately figure out what you need, you'll need your entire vehicle weight and then the front and rear weights, you can do it though just with the entire vehicle weight if you know your weight bias front to rear. also, you'll need to know what your rear spring rate is, as this plays a vital part in weight transfer. There's a good tool online you can use free to help get you right.

Spring Rate Calculator « Ridetech – Tech

As far as increasing travel with a longer spring, it doesn't work that way. The suspension travel is limited by the control arms and bump stops. A taller spring would also require a taller shock/coilover. you'd have to design the control arms to work with the taller spring.

Assuming this is strictly a drag car, I wont get into how sway bars factor into affecting your spring rates.

as for multiple spring rate springs, I personally dont like them. but thats just me, others do like them. I just like knowing what exacting my spring is doing, it's easier for my mind to wrap around when adjusting things. When I was big into roadracing and auto x with my cousin years ago, we simply bought different springs, coil overs are easy to change springs on and we also used spring rubbers to change things up too. All depends on how much playing you wanna do.