Are silencers and resonators restrictive?

If so, what sort of BHP and / or torque would you expect them to sacrifice?

Would there be any performance benefit in running an exhaust with no resonators or silencers?

 

dunno about resonators,but silencers will be, yes. i would think the degree to which they negatively affect the power would vary depending on how much they quieten things down, although it has been said that the loudest exhaust is not necessarily the best one for ultimate performance.. there's a lot more to it than that!

 

Silencers will make a difference, as to the effect on bhp, it will vary from exhaust to exhaust. Milltek for example aren't the loudest of systems but still give impressive proven gains.

 

what about resonators? anyone have any experience with these restricting performance? or are they as good as a straight through?