why do people use turndowns on there exhaust exactly?im getting a new exhaust system welded up and i was wondering if i should get it with a turndown.is it louder?

 

Turndown allows for the exhaust tips or pipe to not be seen. Or you might be talking about the cutouts, which allows you to bypass the exhaust, basicaly running straight out of the headers/manifold.

 

I think your talking about having your exhuast turned down towards the pavement. I know alot of stock trucks even have the exhaust pointing down at least a little towards the ground. As in my 89 chevy, and my 99 f150. The chevy had dual exhaust pipes that ran to the edge of the rear quarter and were cut flush. This allowed the exhaust gases to exit and rise onto the rear quarter panel. With the gases were alot fo toxic and corrosive vapors which stuck to the panel along with the water vapor that exited. Needless to say, the rear quarter panel was the only place on my old truck that rusted. Now, my 99 f150 has the same type of configuration except the very tip of the exhaust is turned down towards the ground a little. Also, it's cut on a angle to help the gases go down instead of up against the rear quarter panel. Diesels also are very popular and have their exhaust facing the pavement for sure.

I hope this makes sense and that this is what you were talking about.

 

I did it because you don't have to spend $75 - $100 for a stainless tip. Though I just did because it helped the sound a lot. Also, turndowns sound a little louder & deeper because it's up under the truck more and angled toward the ground so it reflects upward and kinda resonates from underneath. Doubt I'll do duals out the back again...too common and sometimes hard to get the tips on straight. Also, a lot more expensive running dual pipes.

-AR

 

jackal is correct. there are 2 main reasons for turndowns. first, you can put turn downs so nobody can see your exhaust (mine is around the rear exle, completely hidden unless you look underneath). second, is for the sound. turndowns make the exhaust sound bounce off of the floor and you can hear it better in the truck. they made my exhaust sound a little deeper.

 

as msujon71 pointed out, you're risking having the exhaust gases ruin your truck. Also, if you ever get a cabin leak, you're risking having exhaust fumes leak into the cabin.

 

as far as fumes go, it really depends where you have your turn downs. i have had mine right over the rear axle and i dont have A/C so i drive with my windows down. in the 4 years since i put turn downs on my truck, i have never gotten any fumes inside the cab, and i dont have the slightest hint of rust or damage anywhere near the truck from the fumes. just my $.02

 

I've got a turndown, no problems with rust or fumes. When I first thought about using a turndown, I asked Flowmaster and they said I shouldn't do it because it would make the exhaust sound louder. I don't mind loud, so I did it.

The main reason I used a turndown is because it was a cheap, quick catback: cut exhaust just before stock muffler, clamp on new muffler, clamp on a piece of 45-degree mandrel-bent pipe, and hang it. It dumps just in front of the rear axle. All the performance of a ready-made catback at 1/2 (1/3?) the price.