ccrunner wrote:
So the question is- is 2.25" bump (and conversely about 2.25 droop- 4.5" total travel) "enough" travel for a very small 1300# car? I ask because I have no idea what the stock Miata suspension was designed to give, and although it would be a ton of work, I'm at a place where if I need more travel, I'd better rip it all out and fix it now..- is 4" to 5" total travel common for street cars??
Thats about perfect for daily street cars or you could go to about 2" bump that includes a 1" bump stop which gives you 1.5" of bump total (allowing for rule of the thumb 50% compression of the bump stop) for sportier driving (lowered car of course). This would leave you with 2.5" of droop which would be excellent - don't underestimate the importance of droop for street use as so many people do. Too much can be not so good for the race track but thats the race track, streets have bumps, potholes, varying cambers and undulations to be dealt with. You don't want less than 4" total for street use if you want to retain pleasantness and comfort. Sit the car on it's shocks without springs but bump stops in place and you should have about 1" clearance.
Don't forget that the rubber in you mounting eyes (if have rubber) also give 50% compression and that is part of your travel.
gtivr4 wrote:
I'm planning for 2" of bump and 1" of droop, at a 4.5 inch ride height. So sounds like you should have enough. Obviously you don't want your full bump to have a chance of contacting the frame, so give yourself a little room for error.
If I was running such short travel I would at least be dragging the floor on the road to get some advantage, you have the worst of both worlds there. I use 1/2" as "room for error" on road cars and zero on track cars then add my bump rubbers and have very seldom bottomed out. Unless your going to do a lot of racing increase you droop travel or you'll get bored with the lack of ride comfort and topping out fairly quickly. You can add leather straps or return assist springs to limit droop on track days anyway if required.