My exhaust doesn't have valves and I would like to have a "quiet" mode for morning cold starts. Is there an aftermarket valved exhaust which can make my cold starts quieter than stock when the valves are closed? Or are closed valves equal to stock, and open valves equal to muffler delete?
Varex is a brand I've looked at. Seems nice enough and sounds good enough.
>>27608429>Or are closed valves equal to stock, and open valves equal to muffler delete?correct. you might be able to find some that are stock/quiet, but most if not all will be stock/passthrough for being able to brap around town while still being a good neighbor.
>>27608429you can get a spring loaded version of picrel. It opens fully at higher rpms and stays closed at low rpms. Just requires a couple bolts to install.
https://www.youtube.com/watch?v=8Ffvw1wyXIAMaybe this is an idea>>27608746>correct. you might be able to find some that are stock/quiet, but most if not all will be stock/passthrough for being able to brap around town while still being a good neighbor.The issue is that I want one quieter than stock, just for startups, and I'm not quite sure how this could be done.Also I don't want the tone to be ruined when the valves are open... >>27608858How does it work? If the valves are closed, where does the exhaust gas go?
>>27608893Idk, scottys idea might work here
>>27608893>quieter than stock maybe you can find one That is serviceable so you can open it and pack more material in yourself? or if you have the space under the car you could add some secondary muffling before the actual mufflers so that it'll naturally be quieter and then the same or slightly louder with the mufflers open. no matter what you do is going to change the tone in some way shape or form.>how does it work?It blocks the flow of exhaust forcing it through that mesh and also a smaller exit reducing the noise. a spring version would be set up so it would be closed during normal driving but when you gun it The exhaust pressure would force it open to essentially turn it off, like a relief valve.
>>27608970Just needs an onahole inserted into it
>>27608970>It blocks the flow of exhaust forcing it through that mesh and also a smaller exit reducing the noise.At the initial startup would there still be a considerable amount of pressure forcing the exhaust open? I know with these types of exhausts they're engineered to generally open up after a certain RPM, basically, but I'm not sure how that works during startups.
>>27608994Nathaniel is that you? >>27609008I would have to assume that unless your car warms up at 6000 RPM, it would stay closed or mostly closed during a cold start. however since every engine and exhaust setup is so widely different from each other and these are pretty much off the shelf standardized units, you can't really say with certainty what actually will or won't happen on your specific vehicle without literally measuring the exhaust pressure at various RPMs and then selecting the unit with whatever pressure and spring rate you need for the desired effect.
>>27608893it’s always open, but the opening increases in size as you rev the engine more. At WOT it’s basically the same as not having it in there. I think trust makes them.
>>27608429it's called an exhaust cutout - usually they just dump straight out but you could build whatever you want in theory - it's going to be heavy to lug around two exhausts though
>>27608970Those silencers suck. We shoved one into the exhaust on my friends crx while he was getting it dyno tuned and it lost 75hp on the next run. built b18 on 24psi out of a 6266 for reference.
