[Blueshark]

I just had an 18" magnaflow put on my truck. Small but noticeable increase in power and around 0.7-1.0 mpg increase (during the week I had it). I wanted better sound so I had the muffler shop put on a flowmaster 40 series muffler. I have only driven it for 5-7 miles, but it seems like I've lost power compared to the magnaflow, possibly even from stock!! I'll test it out a bit more this week, but has anyone else noticed no power or power loss from a flowmaster 40?
:cheers:

 

[Lurchdubious]

i noticed an increase over stock with my FM 40. i've never tried magnaflow.

 

[sudden urge]

Your ECU will adjust over time, but I disagree with your change.

 

[Blueshark]

Your ECU will adjust over time, but I disagree with your change.

Why do you disagree? Because of the flowmaster baffles? The muffler shop guys said that there really shouldn't be that much difference.

 

[sudden urge]

Why do you disagree? Because of the flowmaster baffles? The muffler shop guys said that there really shouldn't be that much difference.

I had a Flowmaster on before the Magnaflow, and IMO, the Magnaflow has better flow performance and sound characteristics.

 

[Toomnymods]

over 3/4 of a secnd gain at the track tells me jba evol> banks> any pos flowmaster with baffles

 

[Warp09]

The muffler shop guy isn't to smart.

Quick explanation:

If you want to get somewhere quicker, do you want to go in a straight line, or zig zag through a bunch of places?

With the FM, the air is slowed down and isn't able to exit as fast as the MF. The MF is a straight through design, nothing restricts it.

Thats why MF had the better gains, and thats why FMs made your truck lose ponies. You want it louder, get a 14" MF.

 

[EVO8]

I agree with all the above.

 

[Beave]

My truck came with the flowmaster already on it but i plan to take it off very soon. I dont like the sound at all. From my experience with high hp hondas the straight through muffler like magnaflow not only sound better put perform alot better.

 

[Blueshark]

The muffler shop guy isn't to smart.

Quick explanation:

If you want to get somewhere quicker, do you want to go in a straight line, or zig zag through a bunch of places?

With the FM, the air is slowed down and isn't able to exit as fast as the MF. The MF is a straight through design, nothing restricts it.

Thats why MF had the better gains, and thats why FMs made your truck lose ponies. You want it louder, get a 14" MF.

I agree that the baffles will restrict flow, but the muffler shop guy explained it to me like this: The MF has a higher flow rate than the FM, but both have a higher flow rate than my engine can output. So for instance, if my engine only puts out 350 cfm of exhaust flow and the FM allows 450 cfm whereas the MF allows 500 cfm...it seems that they should both have the same performance increase regardless of baffles or straight through design. Right???

Nonetheless, if my hp doesn't increase within the next week, I plan on going to the 14" MF.

 

[novak57]

i just got the FM, i don't know what you guys are talking about, as far as the sound goes.Buddy of mine got the MF, and i like mine a lot better.Granted, there is a higher pitch sound at WOT, but the SH*t is LOUD! I LOVE IT!!! and its got more power...fo sho:futwice:

 

[Leadsled124]

The muffler shop guys said that there really shouldn't be that much difference.

Ha of cource he did, he probably only sells flows

 

[rgregory1965]

Magnaflow all the way

 

[Warp09]

I agree that the baffles will restrict flow, but the muffler shop guy explained it to me like this: The MF has a higher flow rate than the FM, but both have a higher flow rate than my engine can output. So for instance, if my engine only puts out 350 cfm of exhaust flow and the FM allows 450 cfm whereas the MF allows 500 cfm...it seems that they should both have the same performance increase regardless of baffles or straight through design. Right???

Nonetheless, if my hp doesn't increase within the next week, I plan on going to the 14" MF.

I think thats wrong. The baffles are going to slow the rate of the airflow.

If someone wants loud, check this clip out.
http://s150.photobucket.com/albums/s96/warp09/?action=view&current=20070312203430.flv

The video doesn't really do much justice. Its pretty loud.

Here it is under WOT.
http://s150.photobucket.com/albums/s96/warp09/?action=view&current=M2U00087.flv

 

[Lurchdubious]

^^^^^^^that sounds SWEET.

 

[Warp09]

^^^^^^^that sounds SWEET.

Thanks!!

 

[jt04titan]

i have a flow 40 one in and one out ,,,no loss at all and i have stock air box

 

[Chevy4740]

Here is my Titan at wot with s&b cai and true dual exhaust. Click on pic to see vid.

 

[Warp09]

Here is my Titan at wot with s&b cai and true dual exhaust. Click on pic to see vid.

Sounds good man.

We should make a thread where we can post what our systems sounds like.

 

[CL 8 2WD]

I just had an 18" magnaflow put on my truck. Small but noticeable increase in power and around 0.7-1.0 mpg increase (during the week I had it). I wanted better sound so I had the muffler shop put on a flowmaster 40 series muffler. I have only driven it for 5-7 miles, but it seems like I've lost power compared to the magnaflow, possibly even from stock!! I'll test it out a bit more this week, but has anyone else noticed no power or power loss from a flowmaster 40?
:cheers:

I went from stock to MF and I thought I lost TQ. But after a while the computer learned it and it was O.K. After a year I went to a CORR race oh those trucks sound so sweet LOUD but sweet. So I ran back to the muffler shop and installed a FM 40 turned down before the axle me likey. And the computer learned that as well. Oh but you have to DRIVE IT LIKE YOU STOLE IT.Sounds so GOOD.MF is not much louder than stock.I like tapping the gas a little in a parking structure at the mall (only go there to see movies) and set off all the car alarms.SO FUN.:upsidedow