Exhaust Concerns?

[redrider07]

I have a Flowmaster 80 series muffler with 2.5 inch tips..and stock cat and pipping. Is it possible that I lost some bottom end with that 80 series muffler...even though the cat is stock and the pipping to and from the cat is stock?

I want a little more power and I am thinking of ditching the Flowmaster 80 for a better muffler and higher flowing cat.

What is the best straight threw muffler and best high flow cat to get for the money?

Thanks guys

My mods as of now:
180 T-Stat
Full CAI
***maybe DHP PCM if gas EVER goes down*****

[[ion] C2]

No, a baffled muffler like the Flowmaster should not cause to you lose power over stock.

High flow, regular, and no cat have all been proven to be nearly identical flow.

Paying $2 more per fillup is not a big deal to run 93 octane. If that seriously affects your economic status, modifying a car might not be the best option for you.

[redrider07]

Thanks Ion. Yeah, I can afford to pay the extra money in gas no problem..but I am really debating whether or not its worth it. So, I should keep the Flowmaster...what about a Magnaflow cat and pipping....no difference?

The guys at the exhaust shop said the same thing as you.....I would notice basically zero difference with a high flow cat...they said the stock flows fine?

I was just wanting to get a second opinion though:)

[[ion] C2]

Yes stock flows fine... until it clogs like mine did ha. Exhaust diameter is really the most important thing. Any headers you get will be beneficial, and hardly any muffler out there is really that restrictive. Flowmaster is ironically not the master of free flowing mufflers, it's baffled so the air bounces around inside it. A straight through muffler will flow more.

When it comes to exhaust it really comes down to exhaust velocity. Backpressure elimination is the false base upon people sometimes set up their exhaust system. If you took off the headers it would run like crap.

What you want to do is keep up exhaust velocity, so you must choose a piping diameter that creates a sort of vacuum pull through the system that will help pull the exhaust gases out of the cylinder heads. This is why too large or too small of an exhaust will detrimentally affect performance.

I don't know about the 3400, but I know N/A a 2.25" setup is perfect on the LD9, and for F/I it's 2.5-3.0".

[Alerosaint]

2.5" FTW......2 more weeks!!!!

[Vinalero]

Ion, I thought that it was btw Straight pipe and high flow that there was not much difference.

If I remember right, there was some increase in power from Stock cat to High flow or Straight pipe.

If only I could find this old tread...

edit:
I found the page : http://www.importtuner.com/tech/impp_0610_catalytic_converters/index.html

5 more Hp TO THE WHEELS!!! on a small honda engine is substancial. Now just think what it would be on a V6 that has almost 2 times more displacement. My guess is like 8 whp.

[[ion] C2]

Ah, yep, woops.

stock cat vs. high-flow cat vs. test pipe

http://www.c-f-m.com/images/cfm_svt_pipes_dyno.jpg

The max power doesn't change, but you gain some low end.

[Vinalero]

I suppose it also change depending on the engine type, exhaust pipe configuration and whatever.

Still, its a really nice increase in low end, 6hp difference at 4000, thats a lot on a 4 banger N/A

[redrider07]

What would be the best straight threw muffler for the Alero then...and what about a cat...maybe Magnaflow?

I want a muffler that flows better than the Flowmaster 80 series?

Thanks guys

[[ion] C2]

magnaflow cat
dynomax super turbo muffler

[Vinalero]

Ive heard good things about Dynomax super Turbo mufler as well, they flow really good, but they stay somewhat quiet.

[bryan213]

i noticed that when i had my flowmaster 401 on my car i lost allot of low end tq then i went bacdk to my stocker i knoticed allot more tq

[natedawg9640]

why would you need to be running higher octane fuel?

[redrider07]

I was actually thinking of puttting my stock muffler back on too. I seem to have lost a lot of low end torque with my flowmaster 80 muff, and 2.5 tips...but I dont see how it is possible since the cat is still stock and my pipping is stock.

My car seemed to run better before I put the flowmaster on????????

Do any of you guys think this is possible....or am I imagining this.....you guys notice the same thing with aftermarket muff?????

[[ion] C2]

butt dyno does not tell you of the minimal/nonexistant gains you get with a muffler. your car is louder, you expect it to go faster, it doesn't. this is your perceived loss of power.

@natedawg9640: DHP PCM.

[Redog]

I dumped the 80 and went to dual 44's.

They sound better than the single 80, which can get a little bit ricey at 3500 RPM after a few years. The 44's are deeper and give a nice tone from a LA1 motor. I have neaders though, that does make a differecne too.

Do you have a reprogrammed PCM that requires 93 octane? If not, you're wasting money. 1 at the pump and 2 with lower MPG ;)

My PCM is set to run on 91 or better, so I put in 91 ;)

[TheMeaningOfLife]

The dynomax super turbo muffler sounds alright, it did help make it a lil iddy biddy bit more peppy at the low end, but damn does it get raspey when you get to the higher rpm's. But its nice and low ate low rpms and half throttle.