Ok, so recently I just had some exhaust work done on my SS. I had the res removed and replaced with a 16" highflow pipe, the u-bend removed and the mufflers removed. It sounds freaking awesome. Very little drone...but I keep reading that no mufflers can cause a drop in back pressure. Some people say its true and some say its bs. But really I'm just trying to find the truth. I'm trying to get the best performance from my ride and I'm just worried.

I had recently looked into getting Chambered or turbo mufflers if they really make THAT much of a difference but before investing the money, does anyone have a definite answer about the back pressure issue? I'm also thinking of making a fwi when i get some time

 

All motors run on back pressure....

Unless your running an ultra high HP Motor... (rail or funny car)
That's the only type that doesn't require Mufflered Back pressure....
Your going to find over time... Fuel mileage will significantly decrease as well as HP... Your best bet IMO is to run Chambered Mufflers.. or some kind of "baffled" muffler. (That's just useing common sense)

 

No mufflers = no back pressure

 

Doesn't it?! I love the way my LS sounds now.

I'm going to have to disagree with you on that, I've had my "straight pipe" exhaust for about a week/week and half now and I've noticed a pretty good difference in gas mileage, and picked up low end power. It pulls pretty hard now from bottom end and slightly less top end.

I'll have to get back on you for the over time part, but as first I kinda didn't notice anything, but once my car adjusted to the better flowing less restrictive exhaust, that's when I noticed a pretty good pull bottom end, and a little less at the top.

I don't see how overtime it can cause a significant drop in mpg's and power when there is no code thrown, and has a lot less restrictive exhaust flow.

 

i thhought the less back pressure the better

 

Over time.... It WILL take its toll...

Usually burnt valves for openers... theres no code for burnt valves...

The back pressure is all inclusive for top end power!
Who needs low end power in a front wheel drive vehicle?

 

Back pressure is part of making a gasoline engine run properly. They're tuned from the factory to operate most efficiently with a certain amount of back pressure. Changing it does affect performance.

 

I don't see how that could possibly be BS. Trying to flow air through a muffler, especially a stock type chambered one - vs flowing air through straight pipe- obviously the straight pipe, no muffler setup (or turbo style / straight through) will always have less back pressure. I don't see how anyone could possibly argue against that. Adding any kind of bends in the pipe that force the airflow to change directions (as most chambered mufflers have), causes some restriction, and adds back pressure- that's just simple physics.

Then I wouldn't be spending money changing mufflers- that's not where the big hp gains are made.

 

This is another one of those topics that always seems to become distorted by misunderstanding and erroneous information. Back pressure shouldn't be your concern. What you should be concerned with is scavenging and the velocity of the exhaust stream.

 

Loving your sarcastic remark about the valves. I didn't say having burnt valves throws a code, I was talking in general. If your computer can count for having alot better exhaust flow and self adjust (which I feel like it did, from feeling the difference after some time) I wouldn't see how it would magically burn your valves anyways.

Who needs low end power in a FWD? I do! lol it's so much more fun that top end power, you usually don't go past 50/55mph on the side streets anyways. My buddy has an SRT-4 and low end power is awesome when it pulls you into the seat lol you just gotta experience it.

BUT. To each his own