Which header system is best for a 2003 4.8 Silverado 1500, and are shorty headers worth it?
We haven't verified specific header part numbers for the GMT800 4.8, so check each maker's application list for your cab, bed and drive.
Last updated
Are shorties worth it? Modestly. Shorties generally flow better than the stock manifolds, but they almost always make less power than long tubes because the primaries are short and unequal. On a stock 4.8 the gain is small either way. A rough generalization is 5 to 20+ hp from aftermarket headers, with the bigger gains on heavily modified engines that move a lot of air. How much you get depends on displacement, compression, cam and tune.
| Type | Good at | Trade-off |
|---|---|---|
| Long tube | Most power; best scavenging | Needs room and ground clearance for the collectors |
| Shorty | Fits tight or lowered chassis | Almost always less power than long tubes (short, unequal primaries) |
| Stock / performance cast manifold | Compact, fits, low maintenance, quieter | Least flow; performance manifolds are a compromise |
On an EFI engine, a tune helps you get the full benefit from headers. Check local emissions rules before removing factory parts.
For a 2003 4.8 Silverado, we recommend long-tube headers; shorties are a waste of money because the factory manifolds are already designed like shorty headers. Long tubes won't bolt to the factory Y-pipe, so you'll need a matching Y-pipe (cats can be welded into an off-road Y-pipe later). Headers are bought to fit the chassis, not the engine, so a set that fits a 4.8 also fits a 5.3 or 6.0. Options include American Racing Headers (~$1,500, catted or catless, bolts to the factory cat-back), Kooks (~$1,550 with catted mid pipe), Stainless Works (~$1,300, 1 3/4 in primaries with 2.5 in collectors), Texas Speed (1 7/8 in long tubes) and Pacesetters on a budget.
Check this first:
- Confirm the headers are listed for your chassis
- Plan the Y-pipe and whether it will be catted
- Plan a tune to get the benefit from long tubes
Careful: Running without catalytic converters may not be street legal and can set emissions codes.
Based on what we've seen work across our own builds, our friends' builds and the wider LS community, reviewed by our lead shop tuner (over 20 years of LS and LT tuning experience). Every combination is different, so use at your own risk.
Go deeper
Check this first
- Check the stock manifolds for cracks and broken flange bolts first; many 'need headers' cases are just blown gaskets.
- Decide the goal: towing/daily manners favor stock manifolds; power favors long tubes.
Try this, then this
- Keep stock manifolds for a tow rig or budget daily.
- Step to long tubes (skip shorties) when power is the goal.
- Tune the ECU to match the header change.
How you know it's fixed
- Header install complete with no exhaust leaks; dyno or datalog shows expected gains.
Still not fixed?
- If a leak persists at the flange, resurface or replace the manifold/header gasket; persistent leaks skew O2 readings.
Key numbers
| What | Value |
|---|---|
| Long tubes or stock | When asked whether shorties are worth it, the blunt answer is no: waste of time and money, long tubes or stock. |
| Shorties a waste unless replacing manifolds anyway | Shorty headers for these engines are damn near a waste unless you have to replace the manifolds anyway; go long tubes or leave it alone. |
Every option we know of
| Maker / product | Part # | Fits | Price | Where | Status / notes |
|---|---|---|---|---|---|
| ARH / American Racing Headers Long-tube headers, 1-3/4" primaries, catted or catless Y-pipe options | Silverado/Sierra 4.8/5.3 | about $1,500 (approximate; exact price not sourced) | americanracingheaders.com | In production Premium price | |
| Kooks Long-tube headers with Y-pipe options | Silverado/Sierra 4.8/5.3 | about $1,550 (approximate; exact price not sourced) | kooksheaders.com | In production Premium price | |
| Stainless Works Long-tube headers | Silverado/Sierra 4.8/5.3 | about $1,300 (approximate; exact price not sourced) | stainlessworks.net | In production Premium price | |
| Pacesetter Long-tube headers, budget option | Silverado/Sierra 4.8/5.3 | about $300 (approximate; exact price not sourced) | summitracing.com | In production Finish rusts; occasional flange fitment work | |
| GM Stock 4.8/5.3 exhaust manifolds | Silverado/Sierra 4.8/5.3 | about $50 used | Junkyard / GM dealer | Discontinued / used only None; best daily/towing value |
Prices are approximate as of September 2026. We list every option we know of, including small shops and used parts we can't link to. Confirm fitment with the seller.
Time and cost: Budget long tubes ~$300-$500 installed over a weekend; premium systems $1,300-$1,600 plus tune.