i am getting new front springs.
will standard 5.5" OD springs work?
i think i remember hearing that they will fit just fine.
if so then what do you think about a 11" 900# spring.
it should give me 2.25 inches drop without any spacers if i did the math right.
i can run a spacer if i need to raise it up a bit

 

I think you'll need the springs with the flat end/ open end so they fit the k-member and a-arm. I'm not sure about the drop, though. Been a long time since I did my research in that department.

 

i was going to get closed and ground / closed.
thats how the stock ones are i believe

 

The top is 'flat', and the bottom is 'open'... at least that's how I'd describe it.

For what it's worth, I'm planning to get 9" 750# springs with weight jacks (my street set; my track set will probably be 850-900, same or a little less height). The jacks are about 1 7/8s thick when all the way down, with about 2.5" of adjustment. So figure a ~11" tall 750# spring. From what I'm told, I'd be able to sit the car on the bumpstops with the jacks all the way down and be about 2-2.5 down from stock all the way up. From the information I've found, I would think that you'd want a little taller than 11" tall with a 900# to be 2-2.5" lower than stock.

 

here is a chart i whipped up
remove the .doc from the end so it will be .xls]
feel free to change values around however you want.
the formulas for drop are dependant on force, free length, and rate

 

That's some really nice work. That formula's (the one with the free coils, rates, etc) been on here for a while, but no one's thought to put it in a Excell or anything helpful/quick. Everyone would just have to weigh their nose (or so I would think) to determine the spring choice. You might want to add that option in the spread sheet. I'd imagine the weight of the car would play a major role in the choice of springs. I'd like to see how it plays out in the real world.
Seems like it'd give me a ~ 3 inch drop on the jacks with the jack 'closed'. I need to weigh my front and see how that changes it.

 

i got the weight and force from a buic GN forum. hopefully that was for our cars now that i think about it.
oops

ok, well now i need to take some measurements.
any of the aftermarket suppliers want to step up and give me an a-arm motion ratio?
that would be distance from bushings to ball joint divided by distance from spring mount (on center) to bushing

 

Give Sam Strano a call. He'll be able to help you a great deal, I would suspect.