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small performance gain?

Discussion in 'Performance & Fuel' started by racer58, Jan 14, 2009.

  1. racer58

    racer58 New Member

    Well hello everyone I have questions right off the get go

    Ok well my dad has a 03 5.3 silverado z71 ext. cab with a lil over 40,000 on it well maintained and im in charge of tryin to get it a lil more umph but all stock for now. I am towin a 26' enclosed trailer with a 2500 lb. modified, spare tires, fuel, toolbox, various tools, trailer itself weighs around 4500 bare.

    Ok now what the plan is just to get a lil help Ive been searchin around for awhile for what to do to get a lil more power but not puttin on no turbo or supercharger. To start id like to put a cold air intake on pretty set on the summit/k&n intake don't know if anyone else knows but summit sells a k&n with their name on it instead of k&n for $70 cheaper. Will this do anything or will my dad be wastin his money i dont want him to do that.


    Also just a different muffler not full exhaust not even cat-back jus take out that huge tank underneath their and replace it with a magnaflow im thinkin. will this help at all or not worth it unless u get at least a cat- back exhaust.

    My original plan was to jus buy a programmer and from what i have seen i thought the diablo predator seemed to be as close as u can get to a custom tune. Being able to jus plug and play and not have to have someone mess with the computer itself. He couldnt justify the 400 for the small gain so i came up with the cai and muffler for $100 cheaper.


    Any suggestions would be greatly appreciated
  2. 04sierracrewcab

    04sierracrewcab New Member 1000 Posts

    The "off brand" Intakes serve the same pourpouse as the KN!
    Im not sure on gains w the magnaflow, but It will reduce some constriction which is always good!
  3. sheep

    sheep New Member

    actually a turbo, taken care of and at the right PSI, can be a very reliable upgrade, saving fuel alot, but it is expensive

    the CAI will help a bit, my advise is to get the muffler but also do a bigger pipe in with it. and a TB spacer could help a little more too. it will give you a little extra MPG when your not pulling that trailer
  4. racer58

    racer58 New Member

    Thanks for the replies guys I drive home from college every weekend to work on the race car and i drive right past summit on rt. 76 in Akron Oh. So i dont have to pay for shipping. Thats always nice. I will get the summit/k&n cai and the magnaflow muffler but i think i will just leave the stock tail pipe.


    Older guy that helps us on the car said even a 5hp gain you could feel the difference towing so we will see i guess come race season

    I think after awhile after both things are on ill add a programmer dont wanna really get to the internals since this is a truck not a race car
  5. lube70

    lube70 New Member

    go with exhaust

    Put the Magnaflow exhaust on it and WOW...what a difference...Cat back duals...Gained almost 3 MPG

    Don
  6. racer58

    racer58 New Member

    Got both the cai and just the magnaflow muffler put the cai on last night in under an hour. First when I opened the box summit had put the right kit in it but had put instructions for for f-150 and expedition. So had to print directions off internet. Then one of the grommets with the studs on it whoever manufactured it didnt thread the one end so we had to put 1/4 threads on it when it was supposed to be metric dont have any metric dyes.

    Leavin to go for breakfast here in a few with some buddies ill take the truck and see if we got any gains. After that were guna head over to this muffler shop that does fairly cheap work and welds everything in real nice. So I can get the muffler put on. Just did my buddies truck and the welds look damn near perfect.

  7. dwill3015

    dwill3015 New Member ROTM Winner 1000 Posts

    You're on the right track with the CAI, and the exhaust would help for sure (getting it to breathe better at both ends) so let us know how she runs so far.
  8. racer58

    racer58 New Member

    Got the small performance gain

    Definitley a gain just with the cai. On initial acceleration and then when you need it to pick up at mid rpm it gets right up and goes. I have heard some of these and it sounds all bogged out then it whistles like crazy but this k&n didnt do that one bit but it makes the motor sound beefier. Got the muffler put on today also when I got the the custom exhaust shop someone pointed out to me the steam coming out of a whole in our stock muffler guess we got this magnaflow just in time.
    just had to add about 5in. of tubing to the existing tail pipe to make it work guy fitted it all up tacked it made sure it was all snug then finished welding it real good welds did it for $30. I was definitley happy with that. Then i pulled it off the lift drove it out and nailed it out of the parking lot.
    Wow this 5.3 has really come to life now. I wasnt really thinking it was gunna do much but it definitley gets up and goes now. Has a very nice deep rumble to it not even all that noticeable in the cab which we didnt want. but from outside it sounds like its got some muscle in it now. The real test will come april when we tow the car to the track for the first time with these add-ons
    Thanks for the replys definitley helped me make the decision to get the cai and the muffler and am definitley happy with it.
  9. cascott325

    cascott325 New Member 1000 Posts

    some more cheap upgrade you can do, is to go with (my suggestion) ac delco irridium spark plugs. the ones i got are the same ones that go into a corvette. also im assuming you have coil over so you wont need to do the distributor, but change the wired to a bigger guage. go with 8.5 or 9mm wires. try to find something with a lower resistance and you will get more spark for a better burn out of it.collinsperformance posted an link in here about changing your clutch fan for an electric fan that seems to be very low budget, so try to search for that thread. it will help with horsepower gains.

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