i got into an accident a couple days ago... i tweaked my chassis... will the performance of the car ever be the same? (assuming all dimensions are corrected to factory specs)

 

If you have a good body shop, with a good frame machine, and if they know how to use it, and if they return the car to it's original specs, then you should be fine. That's a lot of "ifs", and there is large chance that one of them does not apply.

First, find a body shop that deals with your local SCCA (or other racing organization). More then likely, they will have a lot more experience straightening out cars then your average shop, with MUCH more demanding customers. Then, ask people who have had their car serviced there how it aligned and drove. If everything is favourable, you should be in good shape.

Straightening a car properly is an art, and they can only attempt it ONCE. It's an all or nothing thing, and if they screw it up, they can't try again. Seeing a frame machine in operation is actually quite impressive, and very scary (especially when it's your car).