will an RB presilencer reduce gas mileage? I have a corksport exhaust and i've used the silencer which came with it a few times, it is a simple bolt in the tip silencer which does a reasonable job at reducing the noise for only 23$ but I've noticed a drop in gas mileage. I know RB presilencers are WAY more sophisticated but haven't found any info on their affect on gas mileage.

 

No

 

the silencer creates a restriction in the exhaust. the presilencer is a muffler that replaces the cat which gives you more flow.