For years we've been running the factory SLP muffler that was part of the SS package. It really has a great sound, but it's just too restrictive. My dad dyno'd the car a while ago and then dropped the muffler and picked up 50 hp at the wheels. This is a daily driver, so it has to keep it's great sound. Nothing raspy.

I can't remember what flomaster the guy recommended, but it's going to keep both tips coming out the left side only.

What does everyone think?

Thanks,
Steve

 

i would say loudmouth on a budget gmmg if not on a budget. From what ive read on these forums, flowmasters arent the best for f-bodys.

 

I've had a Flowmaster Exhaust setup on my 94 for the last 2 years, Flowmaster Single Chamber Mufflers. They work great, I've never had a problem with them, they don't rattle out, and they give a GREAT sound. Wouldn't replace them with anything else.

 

"dropped the muffler and picked up 50 hp at the wheels"

That would seeem impossible to me... thats a huge amount of HP seeing as with a cutout most only get about 10 hp...

Most people dont like Flowmaster because they are pretty restrictive probably more restrictive than the SLP 2OTL that is on there now. Im assuming with a 396 you must be running headers? If not you should get some, then consider a Hooker catback for cheap money, or perhaps a SLP loudmouth for (very loud W/headers) but ver low restriciton for about $300


good luck

 

you went 12.96 @109 with just those mods? Thats awesome

 

I recommend a Dynomax Ultraflow. I have a 2OTL Ultraflow. It sounds great and is a straight-through style.

 

I can see the 50 over the stock muffler on a 396. The flowmaster is better than the factory muffler, but the Ultra flow does flow better, but I do beleive the stock replacement muffler is only a 2.75 dia inlet. Do you have a 3 inch I pipe?

 

About picking up 50 hp...this is what I rembered my dad saying a while ago. Maybe it was 30 or something....but it was something substancial.

Anyway, I talked to flowmaster and they said the 30 series is 3 in and 3 out...would be great for this application. Right now this car is dynoing at 375 to the wheels.

Now this muffler dude said the 40 series is the way to go. He said the 30 series would be way too loud.

So who do I trust?

Got LT1....flowmaster is restrictive? More so than the SLP muffler that's on here now? I've never heard that before. By all means, let me know why you think that.

Thanks everyone,
Steve

 

The SLP 2OTL outflows anything listed above. I don't know why people knock on the SLP 2OTL. It is a great muffler with a great sound. Maybe you have a restricter inside of the muffler. Some come with them. Remove that and you will gain some flow. The 2OTL is plenty good for your application.

 

I just spoke with my dad on the phone, he said 20 hp was what they picked up on the dyno when they dropped the muffler....that's a lot of back pressure.

Sorry about saying it picked up 50 hp....I really wasn't thinking.

Steve

 

When people say flowmasters dont flow too well, they are referring to the crossflow design mufflers. I have however never seen a dyno comparison to back up any of theses claims.

I have seen dynotests of the conventional style flowmaster mufflers and they do just as well as anything else out there. I think the flowmaster would be a great choice if you like the sound. Especially if youre running one of the more conventional style mufflers with both outlets opposite the inlet.

 

i have never seen dyno proof either, but i went from flowmaster to hooker and gained half a MPH at the track.

i would go with a 4" mufflex or a spintech if u are worried about flow. if u just want sound or have cutouts to undo at the track,the toss the flowmaster on .

 

Magnaflow is a great choice. Stainless and reasonably priced. I like my Magnaflow WAY more than the Flowmaster kit I had on my last bird. The Flowmaster sounded like ***.

 

That's what I like to hear! Flowmaster is definately the best sounding exhaust(when coupled with headers) out there!

 

SLP 2OTL is one of the best flowing exhaust for f-bodies. It's definatly in the top 5 overall cat-backs in my opinion which include:

GMMG
Hooker
SLP 2OTL
Corsca
Borla

SLP 2OTL is the cheapest stainless steal cat back out of that list, and if you want your cat back to last and your on a budget, that's your best pick. Otherwise, go GMMG no doubt.