Will SLP Loudmouths give any HP gains???

NOTICEABLE Horsepower gain: NO

BETTER SOUND: Matter of opinion.

MY OPINION: I really enjoy the sound.
Here's a link to my install, links to before & after audio for "relative" comparison.
http://www.mustangforums.com/m_619100/mpage_2/key_/tm.htm#647782


~MO

Moses said:

MY OPINION: I really enjoy the sound.
Here's a link to my install, links to before & after audio for "relative" comparison.
http://www.mustangforums.com/m_619100/mpage_2/key_/tm.htm#647782

Click to expand...

What is that loud popping sound at the end of your revving? Was that just a recording artifact?

drbino said:

What is that loud popping sound at the end of your revving? Was that just a recording artifact?

Click to expand...

No HP gain but they sound great. Best thing I have installed for sound gain. As far as popping sound of the exhaust, When you first start the engine the exhaust will pop on decell until the cats warm up. The sound is unburned gas in the pipes. The heated up cats burn this fuel before it can make any popping noise.

Ah, cool! Thanks for the explanation.

We installed SLP Loudmout. There seemed to be a little more horsepower. Great sound...sounds like a true "retro " muscle car. With this exhaust and the removal of HC, very noticeable horsepower....

The thing about the SLP Loud Mouths (a.k.a. muffler delete) is they have a rougher, less refined, true race car sound.

As for the hp gains, if you look at peak hp, no.
However, if, like me, you think the 4.6L is severely lacking in the low end hp & torque department, they do pretty good. At 2400 RPM, MM&FF rated them as having 20 more hp than stock, but more importantly, 40+ ft-lbs of torque.