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Exaust System

Discussion in 'Chevy Truck Accessories' started by Thundare, Nov 19, 2008.

  1. Thundare

    Thundare Rockstar 100 Posts

    Hey guys, iv got a 95 silverado as you can see in my avatar and i would like to remove the mufflers.

    but i dont know if it is legal in the state of Oregon, of course i would leave the Cat's on, it would be dumb to remove thoes, they pose as spark arrester.

    Thanks for your help :great:
  2. devilsalmostfree

    devilsalmostfree Rockstar 100 Posts

    check ur emission laws for oregon!
  3. 04sierracrewcab

    04sierracrewcab Epic Member 5+ Years 1000 Posts

    agreed .. its probably not legal though
  4. i wouldnt bother unless you really enjoy going to the gas station and having a pretty gutless truck i ran mine for a week without a muffler just to see what it did..the fuel mileage went way down and it had almost no torque and it just sounded like a$$..flowmasters sound good but they arent the best for power output there are a few mufflers i can quote with dyno numbers and db levels that are much better than flowmasters or even an open exhaust
  5. The results in HP order:
    1.Flowtech Warlock (open) 374.2 hp/ 333.1 tq
    2.Bassani Real Street 373.7 hp/ 333.8 tq
    3.Hooker Maxflow 373.5 hp/ 333 tq
    4.Borla XS 373.3 hp/ 332.6 tq
    5.Magnaflow 372.8 hp/ 332.5 tq
    6.MAC 372.3 hp / 331.5 tq
    7.Flowtech Afterburner 372.3 hp/ 330.1 tq
    8.Hooker Aerochamber 372.1 hp/ 330.4 tq
    9.Bassani 372 hp/ 333.5 tq
    10.Spintech 371.6 hp/ 332.2 tq
    11.Edelbrock Performer RPM 370.9 hp / 331.3 tq
    12.Borla XR1 370 hp/ 334 tq
    13.Flowtech Terminator 369.5 hp / 331.3 tq
    14.Dynomax Ultra Flo 369.4 hp/ 333.2 tq
    15.Flowmaster 369.4 hp / 331.8 tq
    16.Flowtech Warlock 366.3 hp / 325.3 tq
    17.No muffs 365.2 hp / 330.1 tq

    Sound Off in Quietest to Loudest (Decibels):

    1.Borla XS, 80db at idle, 90db at 2,000 rpm, 110db at WOT.
    2.Hooker Maxflow, 80db at idle, 90db at 2,000 rpm, 120db at WOT.
    3.Magnaflow, 82db at idle, 91 at 2,000 rpm, 114db at WOT.
    4.Flowmaster, 82db at idle, 93 at 2,000 rpm, 115db at WOT.
    5.Flowtech Warlock, 83db at idle, 92 at 2,000 rpm, 112db at WOT.
    6.Dynomax UltraFlo, 83db at idle, 94 at 2,000 rpm, 113db at WOT.
    7.Borla XR1, 83db at idle, 96db at 2,000 rpm, 118db at WOT.
    8.Bassani Street, 83db at idle, 96db at 2,000 rpm, 120db at WOT.
    9.Edelbrock RPM, 84db at idle, 93db at 2,000 rpm, 118db at WOT.
    10.Bassani Real Street, 84db at idle, 96db at 2,000 rpm, MAX. (120+db).
    11.Flowtech Afterburner, 86db at idle, 94db at 2,000 rpm, 115db at WOT.
    12.Flowtech Terminator, 86db at idle, 94db at 2,000 rpm, 119db at WOT.
    13.Hooker Aerochamber, 87db at idle, 94db at 2,000 rpm, 114db at WOT.
    14.SpinTech, 87db at idle, 97db at 2,000 rpm, 116db at WOT.
    15.MAC, 87db at idle, 98db at 2,000 rpm, 119db at WOT.
    16.No Muffler, 91db at idle, 103db at 2,000 rpm, MAX. (120+db).

    And I have listed here a muffler shootout test done by CAR CRAFT, they show the best bang for the buck, and show the db's

    The Mufflers
    MAKE MODEL Part No. COST
    SUMMIT Turbo 630125 $14.75
    THRUSH Magnum Glasspack 24214 $16.50
    THRUSH Boss Turbo 17718 $23.95
    HOOKER Competition 21006 $25.95
    DYNOMAX Super Turbo 17733 $28.50
    DYNOMAX Race Magnum 24215 $31.95
    HOOKER Super Competition 21106 $35.95
    SUMMIT Fully Welded 630325 $38.69
    FLOWTECH Afterburner 50322 $39.95

    MUFFLER FLOW TEST

    MUFFLER Flow at 28-in H20
    DynoMax Race Magnum 528.64 cfm
    Thrush Magnum Glasspack 507.40 cfm
    Summit Fully Welded 343.38 cfm
    Flowtech Afterburner 342.20 cfm
    DynoMax Super Turbo 333.94 cfm
    Hooker Competition 232.46 cfm
    Hooker Super Competition 320.96 cfm
    Summit Turbo 331.16 cfm
    Thrush Boss Turbo 297.36 cfm

    MUFFLER Idle dB WOT dB
    DynoMax Super Turbo 89 123
    DynoMax Race Magnum 94 133
    Flowtech Afterburner 92 124
    Hooker Competion 92 122
    Hooker Super Competion 90 125
    Summit Turbo 89 124
    Summit Fully Welded 92 125
    Thrush Boss Turbo 90 123
    Thrush Magnum Glasspack 92 128

    DYNO TEST
    All mufflers were dyno-tested on a 355-cube SBC with 10.0:1 compression, Air Flow Research 190 aluminum heads, a CompCams 292 hyd. a Victor Jr. intake, a Holley 750-cfm double-pumper, and 1 5/8 Headman headers.


    MUFFLER HP TORQUE 2,500-6,000rpm Average
    Hooker Competition 397.4 381.1 286.8hp/351.9 lb-ft
    Thrush Boss Turbo 407.1 384.9 292.1 hp/357.5 lb-ft
    DynoMax Race Magnum 409.5 394.3 298.8 hp/366.9 lb-ft
    Flowtech Afterburner 409.7 391.2 294.8 hp/361.7 lb-ft
    Thrush Glasspack 409.5 389.8 297.7 hp/365.3 lb-ft
    Summit Turbo 411.5 386.3 291.5 hp/357.4 lb-ft
    DynoMax Super Turbo 412.7 387.2 292.6 hp/358.6 lb-ft
    Hooker Super Comp 413.8 387.2 292.8 hp/359.0 lb-ft
    Summit Fully Welded 415.4 390.7 295.6 hp/362.4 lb-ft








    i have another test here on my computer but i don't know how to upload it onto this site because it is in a adobe pdf file.


    more numbers for ya'll who like numbers.

    All tests via an independent lab
    All tests @ 15” wc

    2 “ Straight Pipe 283 CFM
    2 ¼ “ Straight Pipe 365 CFM
    2 ½ “ Straight Pipe 521 CFM

    2 ¼” Typical Bent tailpipe 268 CFM
    2 ½” Typical Bent Tailpipe 417 CFM

    2 ¼” Inlet/Outlet_ Glass Pack Tips- No Louvers- Smooth 274 CFM
    2 ¼” Inlet/Outlet- Glass Pack Tips-Louvered 133 CFM
    Same as above set for reverse flow 141 CFM
    2 ¼” Cherry Bomb 239 CFM
    2 ½” Cherry Bomb 294 CFM

    2 ½” Inlet/Outlet Dynomax Super Turbo 278 CFM
    2 ½” Inlet/Outlet Ultraflow Bullet 512 CFM
    2 ½” Inlet/Outlet Gibson Superflow 267 CFM
    2 ½” Inlet/Outlet Flowmaster ( 2 Chamber) 249 CFM
    2 ½” Inlet Outlet Flowmaster ( 3 Chamber) 229 CFM
    2 ¼” Inlet/Outlet Thrush CVX 260 CFM
    2 ½” Inlet/Outlet Maremount Cherry Bomb 298 CFM
    2 ½” Inlet/Outlet Hooker Aero Chamber 324 CFM
    2 ½” Inlet/Outlet Hooker Max Flow 521 CFM
    2 ½” Inlet/Outlet Borla Turbo 373 CFM
    2 1/2" Inlet/Outlet Magnaflow 284 CFM


    Standard OEM 2 ¼” Inlet/Outlet 138-152 CFM
    Standard OEM 2 ½” Inlet/Outlet 161-197 CFM



    "Recommendations:

    1. Always use a crossover of one kind or another. Our tests indicate that the X type gives additional improvements over the H type.

    2. Mount the mufflers as far to the rear of the chassis as possible. An important characteristic of the exhaust system (behind the headers) is its ability to dissipate heat energy. Heat loss brings with it, gas volume reduction, enabling smaller mufflers and pipes to be used without penalty.

    3. Always us the largest case muffler that you can fit under the chassis possible. The larger internal volume allows additional acoustical energy to be absorbed ,dissipated and eliminated.

    4. Unless an engine is in the 500+ horsepower level or run at very high RPM, the maximum tailpipe size required for minimal power loss is probably 2.5" diameter. When the exhaust pipes and mufflers drop the temperature significantly, the volume of the exhaust gas is reduced and tailpipe sizes is not as critical.

    5. When you must adapt various pipe sizes, always use long tapered cone reducers, such as, those available from Flowmaster. You can also use a crossover that has reduced pipe sizes built into it."
  6. SoonerSilverado11

    SoonerSilverado11 Rockstar 100 Posts

    Wow, great post!
  7. well hopefully it helps there are some decent mufflers out there with good tone and its much better than running straight pipes for low end grunt and fuel mileage..
  8. raisor87

    raisor87 Rockstar 100 Posts

    I have to second nightraven you will hate life if you remove the mufflers completely
  9. catbert

    catbert Rockstar

    GM motors run best with a little back pressure when stock, or nearly stock. Switch mufflers for a better sound, but running without one isn't the answer to anything but hearing loss and harmonic headaches.
  10. Thundare

    Thundare Rockstar 100 Posts

    Lol thx Guys, i did try the no muffler just to hear it, it was a beast, and pissed off the neighbors, IT WAS SUPER FUNNY!!!!!!!:sign0011:

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