I'm designing my front suspension, and trying to decide on shocks.
Seems like a dumb question, but how much overall suspension travel should i build into my suspension for a street ride?
at what % should the shocks ride at? (50% compressed??)
I'm taking all things into consideration, and having a heck of time doing it, lol.

I think you should allow for 3" travel bump and rebound. Some very low cars may not have a full three inches in bump, but try to have 2.5" or so.
You want to prevent the shock from bottoming out, - ever, you want the bumpstops to do that, and protect the shock. The shock shaft will bend if it bottoms, plus it would kill the valves inside.

The shock can limit droop travel, but a droop stop there would be nice.
If looking at coilover shocks, there is usually a bump stop on the top of the shock. be sure to allow for the loss of travel that happens when the bump rubber is added to the shock. In other words, buy a shock with the correct "net" travel, not "gross" travel.
We made that mistake once on a Porsche sports racer we designed independent rear suspension for. We had to move the upper shock mount higher to make it work right.
David

thanks david,
I plotted it out and have about 2.75" net travel in each direction, i'm not allowing the shock to bottom out and keeping about .25" off the bottom-out point of the shock.
I'll probably limit the rebound to about 2.5" just to be on the safe side.
I havent an idea on how to build in jounce bumpers for the rebound yet.
The shock has built in poly jounce bumpers for the bump (closing) side.
Thanks!

Don't forget the bumpstops will deflect, some will squash quite a bit. The Koni stops I have rate out at 150 lbs/in the first half inch then get stiffer as they have a cone shape.
Aluminumm spacers can be made to shim the bumpstops on the shock shaft to where you want them and keep the car off the pavement when bottomed.

The droop stops are probably not needed, I haven't seen any on race cars. As long as the droop travel isn't way out of line. Some coilovers can come loose at the top spring perch and get out of whack. You then have to pin the top collar in place so it doesnt' fall out, or use a "spring tender" which is a flat wire coil spring that is very soft but holds things in place.

My Lola T-70 needs something like that in the rear. but it hasn't come out of place because I don't get airborne in the car. At least not on purpose! I've seen cables and chains used but that's not something I like.
David
David

David,
Sounds good to me, probably the only time the shocks will bottom out is if the front of the car gets airborne (in my case, i hope that happens, as my is being set up as a street/strip ride).
I should set up some sort of limiter, but on this application, where i'm using tubular a-arms and coil-overs, it seems a bit tough.
I dont want to land the bump stops on the coils.

thanks for the idea on the aluminum spacers for the stops, that'll be a nice tuning device.