Spiralmax

Have you heard about the spiralmax? its supposed to add 35 horsepower
it is only 69.99. and is placed on front of throttle body intake. B/S or no?

If you are referring to the tornado fuel saver, I think if it adds 39 hp, that is BS, but it really depends on the car, if the car is Carbureted, then yes it will add probably 15hp tops. The way this thing works is by spiraling the mixture so it is more spread out, (sort of atomizing it some more). so you make use of every 0.001 drop of the mix.

But then again, what do I know?

In best case, you don't lose any power when using one.

Engine manufacturers have spent much effort to produce flow motions as they want them, a spiral before the throttle won't do anything (except add flow restriction), if there were gains from this the engine manufacturers would use it, and make money from it.

Inside a circular tube we always have a "swirl" flow, often this is unwanted as it adds drag.