GT500 axle back adds hp?
6/4/12 | 08:11 AM
#4
Tasca Super Boss 429 Member
Joined: November 14, 2007
Posts: 3,652
Likes: 8
From: Pacific NW USA
I don't believe axlebacks add any power, or maybe just a hint of power. However, my '11 5.0L has just a canned SCT 91 octane tune, GT500 axlebacks, and a K&N air filter (stock airbox) and put down 409 rwhp / 382 rwtq on a stingy Mustang Dyno a couple of weeks ago.
6/4/12 | 10:52 AM
#7
Shelby GT350 Member
Joined: May 18, 2010
Posts: 2,310
Likes: 14
From: CT
That is **** impressive.
6/4/12 | 03:33 PM
#9
Shelby GT500 Member
Joined: December 20, 2011
Posts: 4,354
Likes: 53
From: CenTex...sort of
The only way they could alter the power output is by altering the flow of exhaust, i. e., reducing back pressure. One of the recent videos on Carroll Shelby on the velocity channel talked about the designers going through dozens of exhaust configurations just to get the sound right. It's easy to reduce back pressure, more difficult to produce just the right exhaust note. They're for sound, not increasing performance.
lol
6/4/12 | 06:05 PM
#13
Tasca Super Boss 429 Member
Joined: November 14, 2007
Posts: 3,652
Likes: 8
From: Pacific NW USA
5.0L's with the manual transmission usually put down around 365 rwhp stock. SCT claims their canned 91 octane tune is good for 34 rwhp, so that should have brought me up to about 399 rwhp. Beyond that, I only have a K&N drop-in filter inside my factory airbox and the GT500 axlebacks and I'm at 409 rwhp on a Mustang Dyno. So, that air filter and the axlebacks together are worth about 10 rwhp if my math is right, but I don't have the cash to go back to the dyno to test them individually to see which is which. This combo has been good enough to see a 117.17 trap speed in the 1/4 mile a couple weeks ago, so I know the dyno # makes sense.
Last edited by Five Oh Brian; 6/4/12 at 06:06 PM.
6/4/12 | 06:16 PM
#15
Cobra Member
Joined: October 6, 2011
Posts: 1,571
Likes: 0
From: new orleans
Originally Posted by TheReaper
My car gained 100 hp with the GT500's.
6/4/12 | 06:31 PM
#17
Cobra Member
Joined: February 13, 2011
Posts: 1,399
Likes: 0
From: Southern NH
5.0L's with the manual transmission usually put down around 365 rwhp stock. SCT claims their canned 91 octane tune is good for 34 rwhp, so that should have brought me up to about 399 rwhp. Beyond that, I only have a K&N drop-in filter inside my factory airbox and the GT500 axlebacks and I'm at 409 rwhp on a Mustang Dyno. So, that air filter and the axlebacks together are worth about 10 rwhp if my math is right, but I don't have the cash to go back to the dyno to test them individually to see which is which. This combo has been good enough to see a 117.17 trap speed in the 1/4 mile a couple weeks ago, so I know the dyno # makes sense.
6/4/12 | 06:55 PM
#18
Bullitt Member
Joined: April 29, 2012
Posts: 229
Likes: 0
From: SE Michigan
I agree. I'm sure its adds a couple being less restrictive.
6/4/12 | 07:32 PM
#19
6/4/12 | 08:05 PM
#20
Cobra Member
Joined: August 27, 2007
Posts: 1,496
Likes: 26
From: Southern Al
Wow dude you have some serious issues. The mufflers are made by Ford Racing for the 5.0 Mustang. Look in the mirror before you call me a moron.
Last edited by TheReaper; 6/4/12 at 08:09 PM.