Hi,



I have a single turbo with 3.5" downpipe, 3.5" midpipe and then the N1 exhuast... just installed the mid pipe and the noise is driving me crazy.. was thinking of putting back the cat but ppl are telling me with this setp it will not last long.. and to top it all of the wastegate dump tube is vented in the atmosphere



I do not have any idea how to make a resonator for the midpipe..



can someone explain..



thanks

 

It's simple. Resonators are simply devices that change the ariflow and sound flow patterns by creating or reducing a flow path. If you want to change the note of the exhaust, make it a little quieter; you can simply have a glasspack welded into the midpipe section. If you wanted to go hardcore, I would think that you could tack in some perforated plates (baffles) that are the diameter of the midpipe. You'd have to experiment with how many are needed, but four should break up the sound significantly. Problem with that is, then you're creating an exhaust restriction..



EDIT: Because of the rotary engine's heat output, you need to find a high temp ceramic glasspack.

 

Use a stainless steel wool packed type (like Borla) if you can find a suitable one. I melted the cores in 2 Dynomax bullet mufflers ("hi temp ceramic").



Actually, is it a deep tone that's the problem? I have found that absorptive mufflers (like above) are only marginal at reducing this, although you may get better results by experimenting with spacing (length of pipe between mufflers).