I've never seen this asked (or found in a search) if there's any advantages to putting two presilencers on (N/A in my case, but info on a TII is also good). I would assume it reduces the sound even more but also reduces the gains produced by the exhaust. Am I on the right track here or just plain retarded (I'm asking for it)? This is fact/opinion/numbers, whatever you want.

 

You only need two for a full dual NA.



In general the pre-silencer controls the loud, the muffler controls the tone.

For maximum quiet in a straight through system, go with a longer silencer and/or longer muffler.

sound bite from in back
video from inside

ed
In a turbo you usually have only one outlet, and the turbine is effectively a pre-silencer.

 

Yes, aim for a long presilencer with a good diameter. A lot of them you will find tend to be short (14-18") and very narrow, these really don't do you much good. I think the one I use is about 22" by 4.5" and it works great.

 

do presilencers work well with headers? i had a header that would bolt up to the stock main cat but had a small presilencer(or resonator) from a bonez race pipe cut to fit the 20in gap where the cat would go but i had such a bad leak i could never tell if it was a bearable sound when it all was bolted correctly. i will not put headers back on until i find a way to have a sound not any louder than running a straight pipe to some high flow mufflers.

 

Here you go. A little expensive but yery nice. Look at the presilencer under the road race exhaust system.

http://www.racingbeat.com/FRmazda2.htm

 

It's going to be loud with headers, you can't help it. Even with presilencers it's going to be loud. The header is not going to absorb any of the sound so it's going to be loud.