Hi guys,
I'm brand new to this site, look forward to the info and commraderie. I have a question that should be easy for most of you here. I own a 2001 Silverado with the Gen III 4.8. I use this thing basically to drive to work everyday (80 miles round trip, interstate and highway). the truck has 160,000 miles on it now and runs as strong as ever with no oil usage. What would be the easiest way to gain, say 20-50 hp? Can this be done with bolt ons only? I am currently running the stock type K&N air filter with a throttle body spacer(the only adds I have done so far). Supposedly the horsepower rating for this engine was around 275hp. I want to try to maintain some gas mileage for practical purposes, is this possible or a pipe dream? I know this probably sounds a little silly, but I am kinda new to this.
thanks,
silverj[/B]

 

Welcome to the forum. The rating is at the flywheel, and we all speak rear-wheel but yes, 50hp is definately doable with bolt-ons.
Your TB spacer is doing nothing for you, best bet is to sell it to help fund some worthwhile mods. A custom tune will give as much as 30hp all by itself. Remember, the engine is nothing more than an air pump. Easy in and easy out = efficiency+power.

 

I'd go with a custom tune for sure, some long tube headers, either a cat-back exhaust or just replace the factory muffler with a nice free flowing aftermarket muffler (magnaflow is a favorite around here). The stock intake isn't bad, but it can be modified to help increase the amount of air coming in. That combination should be good for around 40 or so HP I think. If it were me I'd definitely compliment that set-up with a mild cam...if you want to maintain the stock converter, a cam like the one listed in my sig would give a noticeable gain in a 4.8. My cam and tune gave me 9 tenths and 7 mph in the 1/4

As trever mentioned, ditch the tb spacer, all it's good for is noise.

 

a little more than what your askin for but it should do the trick
http://www.nelsonperformance.com/news.htm

 

bud...

you wouldn't happen to have a clip of yer idle would ya? I'm lookin at a similar cam to yours 212/218 114 and just curious what it might sound like.

 

PM JakeBrakeIH

he has my old 212/218 on a 114 maybe he will let you listen to a clip.

his is in a 4.8 with a 5 speed

 

Sorry, no sound clip My cam sounds pretty much stock though, it's very mild. A very well trained ear might be able to tell that it's in there. That 212/218 is/used to be a pretty popular cam, I'm sure that someone has a sound clip of it.