I have an 03 with 6# lower, CAI, 4-way chip that made 413 rwhp and 527 rwtq on the race side. I then added longtubes, hi-flow cats, and Magnaflow single "X" muffler/cat-back. I noticed virtually no performance increase. The tone is very nice but too loud in the cab for an everyday driver (my opinion); better with the window down, but winter is coming.

I plan on an aftermarket blower (likely a KB) in the future. I also know the longtubes and cats come into their own once you start adding more mods. I guess my question is if you had a truck with a KB and all the bolt-ons (stock long block) that ran say 11.50's, how much would it slow the truck down if you put the stock exhaust back on? Obviously it will hurt it but how much? Is anyone running 11's without headers and cats? Maybe NOS is in my future!

Jody

I went 11.97 with a stock Manifolds, Cats, and Bassani

The very next week I went 11.83 with Long Tubes, high flows, and Bassani

But I also had worse traction, meaning the Long tubes gave me ALOT more low end.


Both times were ran with the Following:

PSP Chip
PSP Filter
PSP Fast Air
PSP Breather
PSP 6lb lower
PSP Caltrac Bars
FT Valve Body
JLP Power Cooler
Denso Plugs (IT24's)
Bell Tech 3/4 Kit
Pinion Angle Change
No Hitch or Spare
Full Race Wheels

and 1.6x's 60 Foots

Rest of the truck was stock...

Thanks Richard. It's not absolutely necessary that I get this thing into the 11's. I have much better performing projects, just think it's neat to have a fast daily driver, especially when it's a truck. I'm just sick of the noise. I'm a "walk softly and carry a big stick" kind of guy. I want performance but doing it quietly is also important. I'm thinking that the factory exhaust system isn't nearly as bad as many other vehicles.

I'm going to remove the longtubes, cats, and cat-back today and sell that set-up. Thanks again for the response.

Jody

My 01 L got into the high-12s with the OEM exhaust still on. I then had the JDM, single Magnaflow(14568--internal X-pipe) c/b installed. Only did it for the quiet, lower rumble--NO DRONE(and I'm 64 years old ) sound but I then got to a 12.531 so it didn't hurt my ets.

Dan

Keep your headers and change out to a quieter muffler. Why go backwards?

My question would be "what's a quieter muffler?". The single Magnaflow with "X" is supposed to be the quietest available according to many people I've spoken with on three different Lightning boards. The headers add some noise but the changing from four stock cats to two hi-flows seems to be where the real noise is added. Even the stock muffler on the end of the headers/cats was a lot louder than before, plus it had an ugly "boat" type of sound. The Magnaflow had a good sound but was louder still.

The cat-backs are pretty mellow with the stock manifolds and cats, but the aftermarket stuff really changes the tone.

Thanks guys.

Jody

Im not pushing my truck very hard.. Ive run many 12.1s at 111 with 100% stock exhaust...

the only mods I have:

6lb lower
PSP 4way chip
PSP fast air
Billetflow TB
Lakewood bars
Hoosier slicks

all of this with an air/fuel of 11.1 to 11.7 max

DAMN d00d!! Those times are AWESOME for just a 6#!!

Sals the man, what else can I say

I just happen to have a new "toy" for my truck from Sal that should make the numbers REALLY drop

And what might that "toy" be?

-Mike

here is a hint.. it ran 10.48 with Sal

Ut oh... the good ol' laughing gas?

-Mike

nope, think more along "breathing deep"

Hmmmmmmmm... blower?

Ive had his 10sec Works 112 for a bit now... just need to install it and tune...