I'm not sure what test Sundog7 is talking about, but I have one that showed 12HP from a Borla split rear on a '99 F-150 with a 5.4. Do you have anything that shows 2 HP with this combination?

As for your friend, if he replaced both his intake and exhaust then that would certainly show different numbers than the exhaust alone. Some trucks will gain over 9 HP from just one or the other.

So your friend did two mods, and we have proof that one mod is worth more HP. Sundog7 has a system that will last forever and will sound the same in 10 years. Your friends glass pack will be blown out in three months.

I've gone both routes in the past, and I've learned that extra $$$ for quality components is most often money well spent.

Once again, keep in mind that peak numbers don't tell the entire story. It is possible to improve performance without increasing peak numbers at all.

 

Signmaster: Just to clarify, I have a Borla split rear on a 2001 SCrew w/5.4. I don't know what Taxman's sources were, but I'd sure like to have read them.

 

Sundog,

Was that the dyno numbers for your truck? Just curious. The Borlas seem to do real well in all the tests I've seen.

These sources sound questionable to me as well. Although systems will vary from truck to truck, I've never seen anything to convince me that a muffler alone will come close to even a crappy cat-back.

 

Signmaster: I'm not at all a techie-type. My friend handed me this printout from the dyno with RPM and HP and several other lines. He explained them, but it's been quite awhile. All I remember was that the HP was 12.7 peak, and about 10 in the normal (that is, "usual everyday driving") powerband. I didn't ask to keep the sheet, as getting on a dyno in a real racing shop was Inner Sanctum enough for me.

 

For sound and looks.

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The truck:
Teal 1997 XLT flareside with 4.6L, auto tranny, electronic shift on the fly, 3.55LS and 4x4 ORP.

Performance mods:
Gen. 2 K&N FIPK
Superchip(removed until further notice)
True dual exhaust exiting out the back
2.5" pipe with 18" glasspacks and 18"x4" round chrome slash cut tips

Appearance:
White face gauges
Euro clear corners
01L headlights
Covercraft tonneau cover
Billet pedals
16" Modern© wheels
265/75r16 Wild Country Radial TXR tires
Factory tinted rear windows
Bug deflector
Euro clear corners

Sound system:
Clarion ADX5655z Double Din Cassette & CD
4 Pioneer TS-A6865 speakers

Other:
Bedliner
Bulldog keyless entry/remote start



Click here to see more pictures

 

I got my true duals mainly for sound,and hopefully to open the truck up a little. I used 2 1/4" pipe,with 24" glasspacks and an H pipe about four feet in front of the mufflers. I don't think I lost any low end,and it definately breathes better on the highway. I like the sound most of all,but I may change the whole system out in favor of some Aerochambers,or Ravin Z55's. I don't generally go for premade exhaust systems,but I'm no expert either.
I just like the sound,and the open road power.......98

Magnaflow mufflers sound wicked,too

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98 F-150 4.6 Litre XLT 4x2 Ext. cab
prarie tan/tan int.
Yep,it has alot of stuff installed on it,I just got sick of lugging that huge sig. around,hehe
Come and see my newest pictures@ www.my-f150.com

Everything is shown there,except for the Superchip,Thanks Mike T!!

FENDER GUITARS ROCK!!!

Now,if it only looked like this in real life

 

I got mine cuz' i didnt have anything else to do with these dagburn coffee cans!



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97 4x4 Off Road Package 4.6l, Flareside S/C Dark Toreador Red
www.f150world.com/southernthunder