According to Mustang Monthly Axle Backs are good for about 7 HP

RIchard

 

I'd love to get that Borla catback sound under my pony.......but I'm loving my 5psi max boost on a 4lb pulley too much to yank out any backpressure

Besides, I don't like drawing too much attention to myself. I think the stock exhaust provides plenty of good rumble without being over the top. JMO

 

from AXLEBACK?!?! please tell me they didnt dyno this, or tune with anything else. if you put axleback anything on a stock anything, im finding it hard to believe you're going to find 7 horsies lying around. any torque outta that? no new x-pipe, anything else? did they SHOW a dyno result? sorry, im just looking at a physics book and going nope.

 

Just reporting what i read. Here is the Quote from the article:

According to Steeda, performance after-axle exhaust systems are worth around 7 hp and underdrive pulleys gain 11 hp. But the key is the combination of mods. "With a combination of cold air, pulleys, and exhaust, you're basically going to peg out at around 307 to 310 hp at the tires. That's about all you can do to these engines without getting into the heads or adding a supercharger."

And here is a lionk to it.

http://mustangmonthly.com/featuredve..._0512_steedas/



Richard

 

I found that after putting on SLP Loudmouth axle-backs, the sound was so much louder at high RPMs that I tend to drive at lower RPMs or else it can get really loud and annoy the other drivers/ draw more attention than I usually want. The lower RPMs give less torque. I just write it off to driving differently with the louder exhaust.