I don't, I have steered a couple of times of cars I helped friends build. I haven't finished a car for myself because I am too fussy and often times procrastinate. I also am just too busy with work and saving for another house to concentrate on getting my car finished. I have been out of the racing scene for a little while due to work commitments also.
I have assisted with dyno testing of more engines than I can remember, built a few myself and done much of the fabrication on friends street & strip cars. I have also been fortunate enough to learn from a few exceptional engine builders too.
I tend to lurk more nowadays, I am probably not as up to date as I would like to be, I have forgotten a few things, I am getting old these days, I'm 34 next year