If a guy has a stock 4.8 in a 2003 rcsb 3:73 gears and is looking to add close to 100hp to the ground what should I have as a build list to chip away at as I save money.

I have a CAI. and so far Ive decided to save up for these components to help me get there:

Speed engineering headers
tune(probably black bear)
install the nnbs intake I have(which requires saving for a TB and corvette fuel filter)
Cam( i am learning about cams as I do research)
circle D converter

Is this a list that will net me my goal? this is for a spirited DD truck. Id like to keep it NA.

 

You can throw a lot of money at it trying to get you 100 hp. A "cheap" way would be adding a shot of nitrous.

On my nnbs 5.3 i added cam,port n polished 243s, stall, intake, headers and 4.11 gears and only picked up 100 hp...it was OK until i wanted more power then i added nitrous. That was fun but ultimately i went with boost and when i added boost it made me realized boost should have been my first option since you can pick up a nice kit 3500.

With that said i'd recommend saving for boost.

 

buy a used maggie

 

You asked for opinions, so you're going to get a ton of them haha.

i have a 5.3 that I wanted to accomplish nearly the same goals as you. I also wanted to improve efficiency.

My my list looks like this:

TSP 1 3/4 LTs and ORY
TSP 212/218 .550 114LSA cam
Trailblazer converter
NNBS intake with modded NBS return rails
102mm tb (requires slight porting)
4" intake
e fan conversion

Next on the list if I can find a real good deal is some 243/799s.

I expect 100+ to the ground, but I would also like to increase efficiency 10-12% as well.

 

IMHO You'll need a fairly large camshaft to achieve those goals and either port work to your existing cylinder heads - or an upgrade.

My guess would be...

NNBS intake and larger TB, 228/236 cam or something similar, ported/milled 243/799 heads, LT headers and good exhaust system.

As others have said, boost would be cheaper. (On3 kits start at under $2K)

 

Headers, intake, cam, tune, and dont forget about upgrading the trans with at least a shift kit whether transgo or sonnax performance pack, and at the very least a higher flow muffler, if not a full exhaust system! Torque converter, trans mods and gears don't necessarily increase actual hp, they do more for getting you into the power band quicker, and tend to help with the butt dyno as well!

 

Are you talking about 100 at the flywheel or 100 at the tire? BIG difference.

100 at the flywheel would be possible with the right parts. 100 at the wheels will require juice or boost. Doing it NA could be possible but it would require some mods that aren't exactly a bolt on, but you could bolt in a high compression 370 with head/cam/intake and that would get you pretty close

-Avery

 

What does a stock 4.8 make to the wheels? Low 200s?

A 4.8 with heads/cam and supporting mods should be able to make over 300 RW.

This build made 479 flywheel, with even 20% loss from drivetrain and the accessory drive that "should" be roughly 383 RW. Even say 25% loss, that's 359 RW.

4.8L VS 5.3L Engine - Tech - Little LS Slugfest - Super Chevy Magazine

 

drop in a 6.0 LQ9 shortblock with 243 heads from Proheads.com and a cam of choice.
You have the rest of the parts needed to complete the package.

you will gain Substantially more power than what a built 4.8 DD will get ya and give you a Solid foundation for when you decide its boost time. Plus the gains on the bolt on 6.0 will be FAR greater under boost than that 4.8 and cost less.

Dont get me wrong, a 4.8 is proven performer with boost. but its got NO ***** out of boost.

 

I dunno. If you are to believe manufacturer claims: a cam, head swap, LTs and a tune is good for a solid 100hp lol. Most aggressive cams are claiming 50+. Heads, intake and LTs a proven 50+ in most combos.

With the 4.8, just rev it higher to get more power lol.