No Exhaust ?

[Ricardo]

hey guys, I was just wondering (since my exhaust is the worst exhaust in the face of earth) if I remove my exhaust and shoot straight out of the o2 housing is there a risk of burning anything (or becoming deaf ?)

Thanks!

 

[echo]

you would go deaf and if you are running rich or something happens that you get unburned fuel going through there, you will possible be buying a new car.

 

[Ricardo]

alright thanks. So I guess my best bet is to cut the exhaust and have just a downpipe...

 

[FourG63 97GST]

thats is very loud, an from my experience you lose power. getting faster spool up is the only benefit I see youll have from running open downpipe.

 

[Ricardo]

I really doubt you lose power because you will be free flowing the exhaust gas with no backpressure. Darren said he gained 11hp on the dyno when he removed his exhaust and left just the downpipe.

It's probably gonna be too loud for daily driving though and cops are gonna harass me

 

[JayHass]

Originally posted by FourG63 97GST
an from my experience you lose power.

Oh really? What would that experience be?

Turbos run best and make the most power with no exhaust at all.

 

[FourG63 97GST]

ok darren has like what 550hp? and gained 11 when removing the exhaust. how much do you think ull gain?

and reason I said that is I remember going WOT one time and my testpipe blew off, I felt a instant power lose. an I run a full 3" not alot of backpressure there either

 

[bottledbird68]

It will definitely be too loud for normal driving! I just had the guy in the muffler shop next to my garage bend me up a 2 1/2" exhaust from the turbo back. I'd heard a GN with no mufflers before and it didn't sound too bad so I said ahh, we don't need no stinkin' muffler in there. Now my car sounds like a pissed off lawnmower .... OVER A LOUDSPEAKER!!!

 

[candela]

Yes ricardo you can do that. it wont be ass bad as there vaginals say it will be Beleive it or not the turbo makes for a much quieter exhaust note than a natural aspirated car or somethign with more than 4 cylinders...

Oh really? What would that experience be?

I woud also like to know ....

 

[Ricardo]

Originally posted by FourG63 97GST
ok darren has like what 550hp? and gained 11 when removing the exhaust. how much do you think ull gain?

and reason I said that is I remember going WOT one time and my testpipe blew off, I felt a instant power lose. an I run a full 3" not alot of backpressure there either

it was on his civic. 250 hp all motor, no turbo. I believe the hp gain will be much bigger on a turbo car...

 

[Margul]

well Ive heard stories of people with exhauste that short. I dont know if its true buy between the explosions cold air could rush in your combustion chamber. Now hot metal and cold air dont mix to well and it would result in a new engine.

 

[RipperXX]

um i duno about a 4cyl but on a 350V8 well to make a long story shot the exhaust manifold got practicly broke and the noise was so damn loud the base i guess you would call it was shakeing my skin.. and vibrateing everything around.. was kinda funny seeing fire come right out of the block though

 

[UltraImports]

just run a normal exhaust man....

 

[JayHass]

Originally posted by FourG63 97GST
ok darren has like what 550hp? and gained 11 when removing the exhaust. how much do you think ull gain?

You have a lot to learn...

and reason I said that is I remember going WOT one time and my testpipe blew off, I felt a instant power lose. an I run a full 3" not alot of backpressure there either

That's what I thought. You have no real evidence.

Look it's turbo 101. Turbo's do not like backpressure of any kind, and the best exhaust for a turbo is none. It's not theory, opinion or othewise. It's fact.

 

[Antilles]

In my experience running the downpipe open is mugh louder than running the O2 housing open, at least from inside the car. I would at least have a muffler welded onto your downpipe, I did a 3 hour road trip with the downpipe open and I nearly went insane.

 

[Ryan95tsiAWD]

Originally posted by Antilles
In my experience running the downpipe open is mugh louder than running the O2 housing open, at least from inside the car. I would at least have a muffler welded onto your downpipe, I did a 3 hour road trip with the downpipe open and I nearly went insane.

Correct...I have ran with just an o2 and it was fine....i have also ran with just a DP that was not terribly loud...just rattled the sh1t out of my seat.
NEXT
There is a huge response gain from stock to no exhaust!! low and high rpms...watch your boost it will go nuts.
With my free flowing 3" that I have now (no cat or muffler) it isnt to loud in the car or at idle...but when that turbo kicks in cops can hear me from a mile away....furthermore, I have noticed that, while i have more power, my boost pressure drops off really fast...much faster than having some sort of restriction. gotta find a happy medium...

 

[FourG63 97GST]

yea well maybe you all are right, still havent seen proof.
how about exhaust leaks, guess that give more power too also since you even less back pressure.
anyway after all said and done, everyone runs an exhaust and ill still run mine

 

[Antilles]

AHHHHH I just wrote a long detailed reply and when I submitted it wiped it out!!! Will re-write it in a while

 

[Antilles]

Here we go again. I'm ticked that I have to write it again so this time it will be less detailed.

My downpipe is seperating from the catback. A pretty decent sized exhaust leak. It does feel a bit faster. If the leak is higher up, it could disrupt flow and cool the exhaust gas, slowing it down. that might cause a slight loss in power. But in general and exhaust leak will make little or no difference. As for dropping the exhaust at the DP, it makes a monster difference. Doing so at the track netted me a 109mph trap speed. Huge power difference from what I have on the street. about a year ago I saw a laser do back to back pulls, one with the stock catback, the other with no exhaust after the downpipe. He made 244whp and 268whp respectivly. That a big enough difference for me. When it comes to full 3 inch systems the difference is much less significant, maybe 5hp. its not worth the noise or the possibilty of major boost creep at that point.

I think i forgot something that I put in the other reply but that'll have to do for now.

chris

 

[Ricardo]

Ok Guys, I think I got it now. Another question, is it safe to run leaded 116 gas shooting straight out of the o2 housing ? Im asking this because I dont know what the hell is on that "leaded" gasoline and im afraid it may cause some crazy ass exhaust gas... thx again

 

[Antilles]

Nothing wrong with leaded gas, and it running out the O2 housing isnt bad(read: doesnt make it any worse), but now i remember what i missed from the last post. Running it out the O2 housing is bad. You will have uncontrollable creep, you will cook everything in the vacinity of the O2, your EGT's will go through the roof, it can damage the exhaust wheel on the turbo, and it can possibly burn the valves, although on a turbo car that is less likely. Even if you use a pipe that is like half the length of a regular downpipe it is better than nothing.

 

[bottledbird68]

Just a quick thought on leaded race gas, won't it eventually ruin the O2 sensor? I'm ordinarily a domestic guy (new to this whole import thing ) but I know that running leaded gas in a camaro or mustang will coat the O2 sensor and cause it to read different over time, thereby throwing everything off. Now, unless I'm missing something here won't the same thing happen to the O2 in our application too? Correct me if I'm wrong but isn't this still an issue? Does everyone else here run unleaded race fuel or do you replace O2 sensors on a semi-regular basis? Just my .02

 

[Antilles]

well, yeah. it will ruin the O2 sensor eventually, and foul plugs. But i have run about 30 gallons of it so far with no problems. In my opinion it is worth replacing the O2 sensor every year for the extra 10 to 15 octane points you can get with leaded gas.

It'll save the motor under extremely high boost. A new O2 sensor once in a while is a small price to pay.

 

[bottledbird68]

Why not just run unleaded race gas, or is it not available in your area?

 

[Antilles]

the highest unleaded gas i have ever seen is 100 octane. there is a local gas station that sells unleaded 100 octane for $4.50 per gallon, and leaded 110 octane for $4.25 per gallon. leaded gas is so much better that its worth "wear and tear" on cheap replacable parts to be able to run it. When i have extra, i run it on the street.

there is a big difference between the amount of power you can make on unleaded vs leaded.