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Relentless Motorsports
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Discussion Starter · #1 ·
hey i have heard that headers will make a big difference in power.. no i didn't search i want a direct answer. what kinda power increase have you seen? mpg increase? how much and how much to install? what kind and where is a good place to get them?
i have a 5.3
 

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GM Trucks & UA
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Relentless Motorsports
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Discussion Starter · #3 ·
how much?
 

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it's not fast enough
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pacesetter l/t if your on a budget. unknown numbers but track time with a black bear tune was 15.3x coming from 15.7x untuned and 16.0x stock with a hypertech
 

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Team White
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GM Trucks & UA
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I bought my Thorley's off of a damaged truck, used. Search on Ebay and such. In the thread I provided I posted the website with the cheapest new prices I've seen on the internet, right around $500...
 

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Coated tri-ys are around $500, the reg ones are cheaper
 

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HOT AIR BALLOON OWNER
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pacesetter l/t if your on a budget. unknown numbers but track time with a black bear tune was 15.3x coming from 15.7x untuned and 16.0x stock with a hypertech


Too big for a 5.3 dude.
 

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U Mirin' Brah?
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:hmm:
 

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HOT AIR BALLOON OWNER
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Primary and collector size? What size flange?


Think Pacesetter, but in SS. You're better off w/ Bassani for CARB reasons and torque.
 

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Speed Holes
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hey i have heard that headers will make a big difference in power.. no i didn't search i want a direct answer. what kinda power increase have you seen? mpg increase? how much and how much to install? what kind and where is a good place to get them?
i have a 5.3
Do you have smog or emissions testing where you live?
Or are these headers for the Trophy Truck you are going to build?

I'm running the Thorley 310-Y C's on my 5.3 with great results. I have them hooked up to the OE Y pipe with the cats cut out for straight tubing. Runs good, fits great too.
One thing about the Thorleys that people either love or hate is that they do not come with a Y-pipe, but if you are required to have cats on your ride they give you that option, but are great either way. I got mine from autoanything with a discount code for around $450 for the coated version. Good deal IMO.

I felt a power increase of exactly 3 smiles everytime I drive the truck. And an mpg increase of who knows... maybe one frown everytime I look at my gas guage, haha... but that's due to my heavy foot more than anything.

Worst part of install is if you've got the notorious broken off bolts from your manifolds... and if you can't weld you need to get the flanges attached to your OE y-pipe, or a custom ORY made, but I'm assuming this is no issue for you since you plan on building your own trophy truck...
 

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the worst part is that your truck is an 06. your cats are further forward than the 99-05's and it makes for a bitch. you can do shortys (a waste but they fit with no other mods) or some bassani, dougs or tog midlengths or the thorley tri y's but none of those will work with the 06 y because the cats are too close to the manifolds. you will have to do like i had to do and find a friend willing to trade you an older y pipe, that way you can keep the cats. or you can do like azcatfan did and have a custom y pipe made.
 
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