im planning on shaving about 150 to 175 lbs off the front end of my car. i have eibach sportlines and the front springs are 700lbs per inch. im planning on a fully aluminum engine instead of the cast iron block and heads, tubular k member and probably a fiberglass hood. and someother stuff might get removed as well. how much will my front end come up after i lighten it? thanks for the help

 

I'd say around 3/8 of an inch. Maybe more. You could get a 175 weight, put it on the front of the car (safely), measure, and then take it off. That'll give you some idea...at least I would think it would.

 

That 700 lbs/in rate is the spring rate, not the suspension rate.

The suspension has roughly a 3:1 mechanical advantage on the spring; meaning, the suspension has a rate of around 225-250 lbs/in, per side, or about 500 lbs/in total for both sides. So I'd agree roughly with 91's guess; somewhere in the ¼" to 3/8" range would be likely. Not enough to be catastrophic.

That's one of the good things about high-rate springs.... lots of weight makes very little ride height difference.

 

Nothing air ride cant fix!

 

Or a set of Ground Control Weight Jacks...