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View Full Version : An argument against aftermarket exhausts



AceInHole
12-29-2001, 09:20 PM
Here's a post agains aftermarket exhausts on the NICO boards...
basically, he's saying why aftermarket exhausts suck and why we should all get cams instead, leaving our precious stock exhausts on for more backpressure and torque:

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Quote: Look without torque your car wont move easily if at all. Does anyone understand what torque is? power. You may have HP, but without the torque you are going nowhere fast. You need torque to get you moving no matter what gear and rpm you are in.
In racing you will need low end torque as well. At the drag strip you will need it more at take off. On the track, you will need it everytime you come off a sharp corner. Think about what you say before you say it than sound stupid.
Cams: you will not lose more torque than you gain from extra Hp. Its like comparing it to a supercharger. A supercharger takes quite a bit of Hp away at the crank, but then adds again in the boost. The boost is actually higher than what was lost. So in the long run, you get more.<HR></BLOCKQUOTE>

Any comments??

**DONOTDELETE**
12-29-2001, 09:30 PM
i say if low end power is your thing you have no business here on an import message board. just kidding! but really id just tell someone to get a v8 car if they like torque so much. i have 3 reasons that i went aftermarket on my exhaust.. my old one was shot, i like the way it looks/sounds, and i need it when i go turbo.

AceInHole
12-29-2001, 09:34 PM
basically, i argued that an exhaust helps against torque dropping off across the RPM range... effectively increasing torque where you need it most.... well, at least that's what I said...

b18c1-ek
12-29-2001, 11:53 PM
lowend torque? i dump the clutch at 4500 at every stop light http://www.freshalloy.com/

**DONOTDELETE**
12-30-2001, 01:20 AM
Well, correct me if I'm wrong, i'm no expert, but when you're racing, you're playing in higher RPMs. You won't shift until near the red-line, otherwise, the RPMs will drop below the power-band where you get the most torque. And since you're in higher RPMs, you might as well get more HPs there - which are provided by an aftermarket exhaust. And many people have shown dynos with no loss of lowend torque after the installation of an aftermarket exhaust. So, more HPs, and the same torque... That's what I think...

SilviaDET
12-30-2001, 02:43 AM
well in a NA enviroment then it makes some sence, to a limited degree, in a turbo engine however the less backpressure the better.

Mav1178
12-30-2001, 03:37 AM
This guy is one of the reasons why I will never visit the NICO boards.

-alex

**DONOTDELETE**
12-30-2001, 06:11 AM
in a way that guy or gal is right. whoever gets to the powerband quicker pulls away. thats for street power though. Whatever your application is, you want to have an exhaust that flows the right velocity at the optimum rpm(torque peak). Maybe this persons exhaust was too big and there wasnt good velocity and scavenging at their power peak. lose one to gain another....

**DONOTDELETE**
12-30-2001, 07:52 AM
now this is from a newbie and all, but the some of the guys i talked to about this a while back said the having the back pressure to increase low end torque is just a myth from the old days of hot rodding and that it is not really true.

12-30-2001, 08:08 AM
That's correct. "Needing" backpressure is a myth. What you actually need is flow velocity, which helps cylinder scavenging. A smaller pipe will give you higher flow velocity, but will become more of a restriction at high RPM, which LEADS to backpressure. "Backpressure" is an effect, not a cause.

The fact is that a good aftermarket exhaust that give you hp and not reduce your torque at all, because the factory exhaust system is extremely restrictive.

Asad

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by podboy3:
now this is from a newbie and all, but the some of the guys i talked to about this a while back said the having the back pressure to increase low end torque is just a myth from the old days of hot rodding and that it is not really true.<HR></BLOCKQUOTE>

brtecson
12-30-2001, 08:20 AM
what is nico? http://www.freshalloy.com/
never heard of it.

-brtecson

12-30-2001, 08:31 AM
Nissan/Infiniti Car Owners (Club). www.nissaninfiniticlub.com (http://www.nissaninfiniticlub.com)

Asad

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by brtecson:
what is nico? http://www.freshalloy.com/
never heard of it.
<HR></BLOCKQUOTE>

brtecson
12-30-2001, 08:37 AM
Ohh.. thanx. Thought you guys were talking bout nismo.com or something.

**DONOTDELETE**
12-30-2001, 09:04 AM
asad that is almost exact on what i was told, it is kinda hard to remember these things when you have not slept for 30 some hours, anyway it sounds like who ever posted this was a dumbass.

blacksr
12-30-2001, 09:36 AM
<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by podboy3:
anyway it sounds like who ever posted this was a dumbass.<HR></BLOCKQUOTE>
indeed.

orion
12-30-2001, 10:07 AM
<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>...Cams: you will not lose more torque than you gain from extra Hp. <HR></BLOCKQUOTE>

This guy's a jackass. He makes a valid point, about gaining more HP than the torque you lose, but the same goes with exhaust, if there is any loss!!!

We all know that helping the engine breath will make you faster, but I/H/E are the basic no or low trade-off bolt-ons. Cams are ALWAYS a trade off...

And without the afforementioned bolt-ons, you probably lose power with cams anyway!!! There's a website where a guy installed Nissan Motorsports cams before adding intake and exhaust and he lost power across the board...click here for the dynos... (http://www.geocities.com/ake2ly/N240/dyno.html)

Later - Brian

AceInHole
12-30-2001, 03:37 PM
Thanks a lot guys.... i'd hate for people on the Nico boards to have to deal with a couple *******s spreading false info.
Asad: thanks again, and on a side note, e-mail me at A7r@AOL.com when you get a chance, I need to pay you for the flange, and possibly the mani :P

**DONOTDELETE**
12-30-2001, 08:56 PM
man even in japan i manage to find myself on fresh alloy! yay.....btw..i told a few of the tuning shops what was said about needing more back pressure....i think they STILL havent stopped laughing...

Nismo Nate
12-31-2001, 02:19 AM
I always felt a exaust on my 240 was absolutly needed, since it's a more TQ-er engine the loss wouldn't matter much to compete with the no-TQ-havin-honda's. I felt it was more of a balance

**DONOTDELETE**
12-31-2001, 02:25 AM
<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by Nismo Nate:
I always felt a exaust on my 240 was absolutly needed, since it's a more TQ-er engine the loss wouldn't matter much to compete with the no-TQ-havin-honda's. I felt it was more of a balance<HR></BLOCKQUOTE>


I sorta agree. We have the torque to spare for a lil hp gain.

3Leater
12-31-2001, 07:46 AM
Don't laugh too much at us old timers. http://www.freshalloy.com/

Backpressure was a very technical term in the late 70's early 80's. People knew what worked and what didn't but not always why.

Now we have young whipper snappers like Asad to throw out the techno babble to tell us why it works and keep us straight. http://www.freshalloy.com/

RickB