Crazy gains from aftercar exhaust

[jas142]

Anyone else find it odd that in the latest edition of 5.0 Mustang and Super Fords, they did a dyno test of different boltons, and the aftercat exhaust netted like 10 horsepower, and the Xpipe only got 5? Why is this the case? I've always heard it being the other way around

 

[mrvax]

Lot of variables in dyno runs. The X will always give better gains than a cat-back.

 

[JonJon]

I felt an increase from my x pipe, felt nothing from the catback. I did the catback first though.

 

[jas142]

Good enough for me, X it is

 

[rx7speed]

you seem to only look at peak numbers
try this

look at the torque numbers
not just peak
but gains through the rpm range instead
more area under the curve is what is important
now how much of a peak gain you get

 

[NFCStang]

you seem to only look at peak numbers
try this

look at the torque numbers
not just peak
but gains through the rpm range instead
more area under the curve is what is important
now how much of a peak gain you get

Righto...I would rather lose 2 hp at the peak and gain 4 across most of the powerband with TQ as well

 

[sl03gt]

In that article the O/R X pipe only gained 3hp and lost a ton of low end tourqe.

 

[Bone Racing]

Lot of variables in dyno runs. The X will always give better gains than a cat-back.

yup

 

[LI98GTStang]

Had they put on the X first it might have been reverse as far as the results.

 

[neoclasiccl]

I noticed a nice gain on my old 2002 GT with a magnaflow xpipe and magnapack cat back but I have to say with the Cobra the power was much more noticable.

 

[rx7speed]

In that article the O/R X pipe only gained 3hp and lost a ton of low end tourqe.

I'm confused
you said 5 now 3 hp


but no usually a x-pipe vs true duals the x has quite a bit more through the range
even vs a h pipe
though in the very very low end the h pipe might make a little more but OVERALL the x-pipe wins from what I usually see

 

[Rustang Cobra]

check out the dyno graph in my signature, thas before adding an x pipe vs after adding an x pipe

gains all across the board with a gain of 12rwhp and 10rwtq peak

i felt nothing from the catback

stock realistic numbers for a cobra are 260rwhp/260rwhp

i put down 260rwhp/264rwtq peak with my catback and cold air

 

[JonJon]

I'm confused
you said 5 now 3 hp

2 different people. 1 said 5 hp, the other said 3 hp.

 

[GNN60GT500]

What kind of X was it? That could be it too...

 

[rx7speed]

2 different people. 1 said 5 hp, the other said 3 hp.

*insert smack me in the head smiley here*

ok so I'm stupid

and whats with the bag on the dudes head?

 

[Ruffrider]

My X-pipe made my car feel like a gain over the entire rpm range from the sotp... probably just my mind telling me "wow, your car is loud so it's so much faster" lol.
My cat-back did nothing but make my car sound insane.

 

[Frank 03GT]

My Dr. Gas X made a nice difference. I used to get beat consistently by my friend's camaro (89 IROC with a 400 CI small block, mild cam, Ford 9", etc.) by about 1-2 car lengths... he'd get me on the launch and then neither of us would pull. Now I pull him pretty hard through 2nd, 3rd and 4th.... even with a royally screwed launch, I can reel him in now.

 

[GNN60GT500]

My X-pipe made my car feel like a gain over the entire rpm range from the sotp... probably just my mind telling me "wow, your car is loud so it's so much faster" lol.
My cat-back did nothing but make my car sound insane.

SOTP difference is really hard to feel on these newer cars....pretty much because the computers adjust and adapt so slowly that the gains are so incremental, you dont really get that SOTP difference right off like on an OBD1 car