I have a 2004 Silverado ECSB with all the bolt on mods. Its a 5.3 auto.
First, you will be lucky to get 240hp at the wheels stock. With a Cat back and air filter you might get an additional 15-20.
That leaves a tune, headers, and electric fans.
Ive got a set of ceramic coated Edelbrock shorties. I got them really cheap, but if they were more money I wouldnt have done it. They made an additional 7hp on the dyno. TOG makes some really nice mid length headers, but they are $700. The stock manifolds on 99-05 trucks flow really well, especially for the stock cam in the 5.3.
That leaves a tune and electric fans. This will be the 2 best mods you will do.
You can PM me for info, and I will send you links to my truck album. I also know a guy who does custom tunes which will give you 30+RWHP.
Electric fans from a 97-02 F-Body bolt in really easy. Have them turned on with the computer, and youve got another 10-15hp.
Get in touch.
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