JD_AMG

If you were building an N/A LS1, where would you put exhaust on the list?

Mike TA

iTrader: (6)

Really? Aren't exhaust and a lid where people usually START on the f-body? They support just about every other mod. I don't see too many cam/head/intake/Nitrous/FI stock exhaust cars rolling around.
I've been doing this **** backwards the whole time?

kingtal0n

iTrader: (1)

When I first got into cars- I felt that way. Exhaust was the first thing I did to my first V8 Camaro. It was cool when I was 16.

Some mods can make you feel special that way. Exhaust was a magical first mod.
Its a cheap way to make you feel like you "did" something to the car.


In reality exhaust is just a means to an end (to meet a goal for driving the vehicle safely). The engine in drag racing terms, would probably be lighter and make more power without much exhaust. We can take care of the entire car first- meet goals for engine longevity, trans durability, power, suspension, economy, whatever. Then quiet it down to an acceptable level last, using a cutout if necessary for true high output situations (> 500 horsepower usually in a V8 application).

The power goal should have nothing to do with exhaust system (you shouldn't be buying a specific system with the hopes of hitting a certain power output number), which need only flow the required amount, and comprises only a percentage of negligible performance for high output configurations (where max flow is stipulated without concern for noise, usually above 500 horsepower in 5-6L applications).

JD_AMG

Its a proven fact that you gain a good deal of power (over 20 wheel hp) with LT headers and full exhaust on LS1 cars. I know you are into the import scene too but these are not civics that potentially lose power from fart cans.

Are you claiming the stock exhaust is lighter than an aftermarket one?
If this is the case you are again wrong, LT headers are significantly lighter than the case iron manifolds and most after market catbacks are either the same weight or lighter than the stock catback on LS1 fbodies. Then there are systems like the LM1 which are significantly lighter because there really isn't a muffler at all.
Again depends on the situation. Stock LS1 cars will gain some power (never lose any) with a cutout. While its only a few it is still a gain.

So answer the original question then. If you were building an NA LS1 for racing, hell lets just say casual drag racing and street driving, would you keep the stock exhaust on?
I know you want to say "just add a turbo", but that is not the question, not everyone wants to add weight, complexity and heat to a "low" hp build, we are not talking about making 700+rwhp here.

JoeNova

I'm pretty sure he came from the import crowd, and posted here over 1000 times before starting his first LS project.

Ignore him completely.

SouthernRex

I thought you were just a troll at first, but now I'm convinced you just don't actually know anything about cars, engineering, or physics. When you learn how 4 stroke motors work, along with cams, exhaust velocity, vacuum\scavanging etc. then come back. The restrictive manifold on the fbody LS1 is holding back power from a stock motor. PERIOD. Maybe your slow little economy Asian car lost power because you did something stupid like going too wide of a pipe (loss of velocity) but going headers with these cars is more power and speed. PERIOD. There is nothing for you to discuss or disagree with. The science has been done for a decade. Especially when the header is mated to a cam with a different overlap etc. It has nothing to do with "you need 500HP for headers to matter." You are so far from reality its getting confusing. It' like you just parrot **** people have said to you without actually knowing what any of it means.

fst100

iTrader: (5)

well, this escalated quick

AnotherWs6

iTrader: (17)

Dude!!! Just shut the F up. JD, please don't try to argue with this tard.

OP - listen to NOTHING this guy says. EVER!!! He just spews garbage in every thread he posts in.

And do not do the loudmouth with headers and no cats, you're going to hate it. I'd do the SE headers and y-pipe. I'd also skip the cutout unless you really want to be loud at the track. It's a fun toy but at your level it's not gonna do much power-wise.

HCI2000SS

iTrader: (2)

I agree 100% on the whole LM1, headers and no cats route! I had that setup initially and hated it....the rasp was ridiculous lol.

LukeDowning

trust me fellas. I know the beinfits of changing out from stock Exhaust..unlike this guy.
hell even the stock Y pipe on mine on the left bank might be a 2-1/2 dia pipe its smashed flat to about an inch in width for clearance. yea sure that thing flows great

fst100

iTrader: (5)

^that's how they are from the factory for clearance btw

AnotherWs6

iTrader: (17)

Yeah, I was pretty shocked and grossed out first time I had my car on a lift and saw the factory y-pipe.

LukeDowning

is the LM2 any quieter?

SouthernRex

Glad to know you have a head on your shoulders and a love of cars. Ignorance like the stuff he's spewing is poisonous to education and knowledge. I tried to be civil for three posts, but I feel like I just keep repeating to myself. It's like arguing with someone from the Flat Earth Society.

LukeDowning

nope just the ricer crowd

HCI2000SS

iTrader: (2)

Yes definitely. The LM2 is more like the other bullet style mufflers out there like Magnaflow, Borla, Dynomax, etc...The LM1 is just a resonator....not a true muffler

kingtal0n

iTrader: (1)

I built a 700R4 trans in 2000, A forged 9.5:1 blower motor in 2001, and a twin turbo V8 with a stand-alone ECU in 2002. All by myself- no shop involvement. Tuned a hundred cars since then. Not trying to brag, just saying this isn't my first V8. Its just my first LS motor.

Try to think of the engine without the car. Imagine it floating in the air. What kind of exhaust do you think it will want? It doesn't depend on the vehicle- it depends on the engine performance goal and owner's noise level desires. If the goal is strictly performance, the resulting shape and size of exhaust will be quite different than if the goal is silence.

Now work backwards with that in mind. A goal of silence means sacrificing power- or does it? Why not have both? Whats the difference between a stock exhaust with a cut-out, and a performance exhaust with a cut-out? In general, a well positioned, correctly opened/sized cut-out will always out perform any full length "performance" exhaust. So all a performance exhaust system does really is cost unnecessary money and creates noise you can't ever shut off. It's like a nice set of wheels- very pretty to the owner, very 'useful' to the owner, cosmetic noise. To others, maybe not so pretty, and completely unnecessary.

I just built a 5.3 single turbo/4l80e. What kind of exhaust system do you think I am using with all this 'knowledge'? Im about to buy a $30 walker muffler with OEM internal baffles designs to keep this thing quiet. And if that doesn't keep it silent enough, I will add another one in series until I am satisfied. I don't give a crap about how it sounds- I don't want to hear it at all. The dial in the cockpit tells the engine how much power to make- not the exhaust system. 20 horsepower? 40 horsepower? You have to be joking me. If the system suffers significantly a cut-out will fix all for those all important "gotcha" moments.

Mike TA

iTrader: (6)

I really like my AR headers, catless y-pipe, and magna flow. Reasonably quiet at idle and cruising. Sounds great at WOT and proven to flow well.


..... But maybe I just got into cars and I'm a 16 year old who likes to feel special
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98CayenneT/A

Op is not building a boosted motor and maybe I should throw my stock exhaust back on my H/C/I car and see how it runs.....I can only imagine

kingtal0n

iTrader: (1)

There is no such thing as a street car for racing. The minute you say racing, those are sponsor cars (teams with excess funds for stuff like R&D). The minute you say racing, you are saying sponsor cars, money to play with, hundreds of thousands of dollars to spend on developing the best of your class. And the vehicle in question loses all of it's street driven weight, it changes completely. You can put 20k just into a racing 'chassis', and that is just to start things off before any drivetrain is installed.

You can't use racing and street driving in the same sentence, and be taken seriously by a sponsor paying hundreds of thousands of dollars to win a race event.

So lets look at an NA race car for a minute. A nascar or something? The point is that the sponsor is paying for the development of parts which fine tune the existing nature of the engine and chassis together, for optimal performance in a very specific application. There is no room for 'street car stuff' or much comfort. The exhaust would need to be tuned specifically for the engine to give optimal engine VE in the range where the engine is kept most often, and that is all that needs to be done besides meeting some kind of class specific noise requirement.

Class restricted stuff aside, we do not 'race'. Our cars, if they have turn signals and dash boards or whatever, drive on the street, and so we are not bound to these racing type rules. Furthermore we do not get 'sponsors' paying for our R&D. So the playing field is sort of an 'anything goes that we can get away with'. So that is how I play the street car game: by setting goals for cost, power, noise, handling, etc... using experience and then try to meet those goals using an anything goes attitude.