Johnnystock

iTrader: (6)

Heres the story; got a defect Muffler from Hooker with their catback. I bought a Magnaflow muffler for replacement and installed it;

I'm 200% sure that I lost a good 20-25hp!!!(even more I'd say) I worked like a dog under my car to fix the problem on a hot day and heres the reward

AND the Magnaflow has the worst sound ever!! First, it wayyyyyyyyy too tame, and the WOT isnt better. The rasp is all gone, but I dont give a ****.

I'm really tired of this stupid muffler situation...

The defect Hooker catback was 10000000000X better and faster.

My Dual Dual was the real deal.

I think I'll just order a TSP Rumbler and call it a day.

Johnnystock

iTrader: (6)

I almost feel like one spark plug wire is unplugged!!

Sladester2

iTrader: (1)

If you're 70+ magnaflow is perfect. Anything below that and it's too tame.

Johnnystock

iTrader: (6)

Internet made me believe that Magnaflow sounded badass, even if in every vids I heard, I was sceptical about getting one. I pulled the trigger for the ''performance'' results I've read, but now I know it aint good for my LS2/LS3 setup.

Latch

iTrader: (8)

I doubt you lost anywhere near 20 hp, I'd be surprised if you lost even 10. But if you want more noise, by all means add a cutout.

Johnnystock

iTrader: (6)

Seriously, I can feel the car isnt even close to loose traction in 2nd at full RPM(which wasnt like that before). Just to feel any difference on the butt dyno, I think it takes around 20hp. For exemple, when I got 16rwhp from my ported FAST, I didnt feel anything in the car.

For the sound, The Hooker was 2x louder, and my original old Dual Dual muffler was louder than the Hooker.

I know it sounds weird to lose that much with a muffler, but theres something wrong for sure. I have a LS2 with ported/milled LS3 heads/ 1 7/8 headers and 11:1 CR, maybe I can leave a lot more on the table than a smaller cube LS1 with Cathedral heads.

RevGTO

iTrader: (12)

Your SOTP is your subjective impression, and there's no basis to question it. That being said, the Magnaflow is a straight-through type muffler. Unless it's also defective, there's simply nothing in it that could cause that kind of power loss.

Johnnystock

iTrader: (6)

I know this subject has been covered numerous times, and I know its really subjective. BUT I've owned this car for 7 years and I'm really used to it. My new engine setup was completed in June and I could easily say I got 40-50hp more than before, ans this is with my SOTP feeling. This was confirm with my tuner(estimated 530bhp to my 495bhp LS1) and I just pulled on a 440rwhp/490rwtq 2jz swapped IS300. I can say the SOTP can be alright sometime.

I can really tell that car accelerate slower than before, that I'm 200% sure. The rear just got rebuilt and I'm wondering if they put a 2:73 in there

Honestly, I would say that my butt dyno feels a 30-40hp loss(my car feels like my old H/C/I LS1 now), but I didnt say that because I never heard of anybody losing that much with a bad catback. But I've seen 383-408ci strokers gain as much as 35rwhp when dynoing with open cutout (with a crappy Flowmaster muffler most of the time).

Johnnystock

iTrader: (6)

If the car doesnt sell next tuesday(buyer is supposed to pick up the car..) I'll get a TSP Rumbler and see for myself what is the result.

MikeWS6

I will never go back to a muffler.

LM1 ftw

Sail Hatan

Do you have long tubes? cause I loved my LM1 until i got headers, then it sounded like horse ****. Magnamouth made it 100 times better but im still not happy with it, so its time for duals.

OP id figure with all that beastly motor under the hood you would have opted for true duals as well?

bayer-z28

iTrader: (14)

Wondering how OP's Y pipe situation is as well..

reds10406

iTrader: (3)

I had an edelbrock cat back on my car when I bought it and it sounded like complete ****, replaced the muffler with a spintech and it sounded 100 times better, then added an ory and kooks headers and its sounds even sweeter. A guy on ebay sells spintechs for $100. I think I paid like $120 for mine a couple of years ago. You could sell your magnaflow and buy a spintech.

bayer-z28

iTrader: (14)

^ My buddy had an Edelbrock exhaust on his foxbody when he first bought it.. Sounded terrible!!!! Sounded like someone screaming into a pillow.. He got that classic 5.0 sound back when he went to the Super44 system.

01ssreda4

iTrader: (96)

Love to hear this bc I know you are speaking the truth, sound wise.

I've looked through Magnaflow oval mufflers and they are straight through, so Im not sure about the power loss part. Maybe the shitty sound is making it seem worse

Sprayed1998

iTrader: (10)

Borla>Anything Else

Johnnystock

iTrader: (6)

My ORY pipe is the newest Y merge design from TSP. I might take a chance for spintech..but Ive been spending more than 15K$ on my SS this year..I might just throw back the defect Hooker haha..but it has some hammer marks on it from removal..

Paul Bell

iTrader: (9)

Magnaflow mufflers are designed to be street legal sound wise. It's better sounding than stock but it's still a muffler. It's no Texas Speed Rumbler-which might get you tickets or headaches on long drives.

SOTP is very subjective. It's like thinking you can torque lug nuts to 80 foot-pounds by feel. Losing 25HP to a muffler means that's gotta be one restrictive assed muffler!

red_cap

iTrader: (7)

just sounds like a case of "not hearing it" horsepower loss. like said before, magnaflow's are straight through not causing much resistance and loss of power. think of all the youtube videos of exhaust installs out there where they say "its much quicker now and 10X more responsive". most of the time its just the loss of sound that tricks you into thinking the car is weaker. i had a flowmaster 10 on my factory SS, then removed it for a quiet straight through muffler (Jardine made for Doug Thorley) from a Yukon cat-back i had....almost like the stock SLP as far as db's but with a better tone. the car didnt "feel" as strong, but i know that this muffler flows way better than the 10 series. just a thought to keep in mind.

Sladester2

iTrader: (1)

Seems like when my car is louder I think it feels slower. Cuz it sounds so dang mean but isn't really goin anywhere lol