Lost low end power after Flowmaster install!!

[Shirl]

I lost A LOT of low end torque with my 3" Borla catback (and I have a blower). BUT, you gain in the upper rpm's because the exhaust breathes better. The best way to see if there were any gains is to do a "before" and "after" test at the track. Do you have any baseline runs from the track that you can compare to?

[Camarorulz]

If anyone could judge accurately how a car performs using SOTP, then no one would go to tracks or get their car dynoed. If anything, you experienced a power change, not loss. I personally experienced no power loss adding just a Flowmaster muffler. You shouldn't be losing any low end at all with a Flowmaster, because it's a little more restrictive than most other performance mufflers. You just psyched yourself out. Don't worry about it.

EDIT: you would notice an exhaust leak though, you would experience a substantial power loss. Go have it checked out if you're that worried. Muffler shops work cheap.

[ August 08, 2003: Message edited by: Camarorulz ]</p>

[Takumi Fujiwara]

The statement is right about losing low end though. I have an eletric cutout on my car, and my fastest runs by 3/10ths difference is when I launch with the cutout closed ( running stock Dual exhaust ) and open it once I shift to 2nd. Cause u shift into a generally high RPM ( with 3.42s ) Im talkin the differnce was like 15.8 to 15.5 Couldnt pass 15.8 running just open exhaust. and couldnt pass 15.9 closed. But my 60 foot was faster closed. 2.2 and 2.3 open. Thats where I saw the differnce. These numbers such Cause my car does- but it shows to me, the differnce in open exhaust ( free flowing ) vs back pressurized.

[Takumi Fujiwara]

O and Dynoed ( again crappy numbers :-D ) 155/170 closed. 165/200 open. But The numbers are a smooth graph closed and the are low then JUMP with the exhaust open. ( the Torque cruze is about the same but it changes enough to notice open )

[Bliggida]

Shirl and Takumi, I shouldn't have to mention that there can and is an overwhelming difference between a full cat-back exhaust made of 3" mandrel bends and just a muffler slapped on the car.

Along side that, you cannot compare a completely stock exhaust with only a muffler up against a car with a cut-out effectively running open headers.

Got to keep it limited to the subject at hand. Muffler only.

[snatch]

"and you're trying to state that your muffler made so much difference you could feel the same as what yielded me over 20 horsepower in effective gains with a gear swap?"
What are you talking about man :rolleyes: I never said I gained anything. I wasnt trying to imply that what felt like a loss actually was, I just wanted to see if there was a problem, and I didnt expect to just slap on a muffler and hall major booty, it was just an observation on my behalf by the seat of the pants meter, thats all. CamroRulz you made an excellent point never really thought of it that way.
Bliggida, Im not trying to start anything with you, but you say your trying to help but it seems to me that you have an extremely brash way of getting your point across.
Oh and I wasnt hating on my flowmaster at all, it was just a concern that I wanted to address. I'll get my car dynoed this weekend, unfornately I dont have a base dyno to go off of. Thanks for all your opinions.
Takumi, that is crazy that a cutout yeilded you that much. What else have you done to you exhaust as well as your intake? Also what year/make ride do you have?

[Shirl]

Shirl and Takumi, I shouldn't have to mention that there can and is an overwhelming difference between a full cat-back exhaust made of 3" mandrel bends and just a muffler slapped on the car.

No kidding Einstein. Just making a point about ANY exhaust modification and how there is a loss in low end torque. Shane, no matter what, even if the car is stock, there should have been at least a slight difference or it should have felt about the same (if you already had a dual outlet stock muffler on there). Listen for any rattles, or hissing in case there is an exhaust leak. Did they weld the muffler on or attach it with clamps? Get under there and shake it a little too to see if anything's loose.

[Bliggida]

That's incorrect. Majority of all exhaust modifications gain torque, not lose it. It is only the racey exhausts that do not gain toruqe - but they never lose what was already there. They merely only gain horsepower.

[snatch]

Hey Shirl,
Yeah I did hear a hissing, like air being let out of a tire, only quieter, I was unsure if that was normal or not, since I mentioned it and noone said otherwise. I felt around the pipes while my friend held a steady rev at 12-1300RPM and felt no air.
I searched for what a possible exhaust leak should sound like but was unsuccesful, any Ideas?
Thanks Shane
P.S. the pipes are welded

[ August 08, 2003: Message edited by: snatch ]</p>

[Bliggida]

<blockquote>quote:</font><hr>Originally posted by snatch:
"and you're trying to state that your muffler made so much difference you could feel the same as what yielded me over 20 horsepower in effective gains with a gear swap?"
What are you talking about man :rolleyes: I never said I gained anything. I wasnt trying to imply that what felt like a loss actually was, I just wanted to see if there was a problem, and I didnt expect to just slap on a muffler and hall major booty, it was just an observation on my behalf by the seat of the pants meter, thats all. CamroRulz you made an excellent point never really thought of it that way.
Bliggida, Im not trying to start anything with you, but you say your trying to help but it seems to me that you have an extremely brash way of getting your point across.
Oh and I wasnt hating on my flowmaster at all, it was just a concern that I wanted to address. I'll get my car dynoed this weekend, unfornately I dont have a base dyno to go off of. Thanks for all your opinions.
Takumi, that is crazy that a cutout yeilded you that much. What else have you done to you exhaust as well as your intake? Also what year/make ride do you have?<hr></blockquote>
You can substitute gain for loss in this instance.

As far as being brash, I gave you the short and sweet the first time...
<blockquote>quote:</font><hr>Originally posted by Bliggida:
You don't lose or gain anything with just a muffler.

Let alone a difference noteable enough to feel. Congratulations you psyched yourself out.<hr></blockquote>

[Shirl]

That's incorrect. Majority of all exhaust modifications gain torque, not lose it. It is only the racey exhausts that do not gain toruqe - but they never lose what was already there. They merely only gain horsepower.

I was talking about a loss in the low end range. High end hp and torque are gained because of the better breathing capabilities in the upper rpms. The powerband is shifted. This could be the reason why he can't spin his tires from a stop like he use to.

[Shirl]

Hey Shirl,
Yeah I did hear a hissing, like air being let out of a tire, only quieter, I was unsure if that was normal or not, since I mentioned it and noone said otherwise. I felt around the pipes while my friend held a steady rev at 12-1300RPM and felt no air.
I searched for what a possible exhaust leak should sound like but was unsuccesful, any Ideas?
Thanks Shane
P.S. the pipes are welded
[ August 08, 2003: Message edited by: snatch

That's what it would sound like.. a hiss. Did it get louder when your friend held the gas pedal? You need to find out where it is leaking. It might not even be the muffler. Check around the cat and even up near the exhaust manifolds. Something's not tight under there.

[Bliggida]

maybe its because he's simply got a tired automatic with 3.08's???

The powerband can shift. That doesn't mean it automatically does.

Exhausts are made to benefit all types of powerbands. You can have one extreme in drag racing to boost top end and horsepower. Or you can get one for an RV or Off-road vehicle that boost low end and torque.

Depends on the application.

Regardless all he did was add a muffler, nothing changed. Much less powerband.

[snatch]

Dude the sig reflects a Y87, which has 3.42 as well as a dual outlet exhaust

[Bliggida]

<blockquote>quote:</font><hr>Originally posted by Bliggida:
maybe its because he's simply got a tired automatic.<hr></blockquote>
There are more than a few factors to tire spinning. Unless you have brute torque, ALL of them play a factor.

Though a muffler will not be one of them. A Cat-back, perhaps. Not a muffler.

Dual exhaust = more power.
Dual outlet exhaust = looks like more power.

[ August 08, 2003: Message edited by: Bliggida ]</p>