I have been racing for what seems like forever,you can kind of get a "feel" for people and tell who knows a little bit about what they are talking about.
There are people who do things once or twice and pretend to be experts,and also people who advertise engines they have or built for sale that make X amount of horsepower with no data to back it up.
If you are in doubt about someone,ask around for second opinions.
I'll be the first to admit,I am no expert on anything.If I think I can help somebody on here I certainly will try though.
Keith