5.3 changes over the years?

[Wayne2]

Does anyone know what changes have been made to the 5.3 during the years of production? The local expert (Thunder Racing) says the '02 and '03s seem to have more h.p. in stock form but don't respond to minor mods like catback, air intake, & reprogrammed computer as much as the earlier models do.

 

 

[MountaineerTom]

Between the '99 and '00 model years (I think), they changed the cam in the 5.3 to the one used in the 6.0 . They gained 15 HP and some torque (can't remember the amount) just with that change.

[Tucson_02Silverado]

'02, No EGR, air box has no baffles like '01 (sshotrods.com), the throttle body and MAF look like 80mm

[k1500chevy97]

2000 to 2003 are 285 hp and 325tq

The 1999 is 270hp and 315tq

 

 

These might be wrong so correct them if they are

[100R1]

'02, No EGR, air box has no baffles like '01 (sshotrods.com), the throttle body and MAF look like 80mm

What did GM do to lower the N0X levels with out a EGR valve?

 

No Baffles in air box, Did they change the size of the Box? the baffles help to reduce intake noise, How did they overcome noise ?

 

Same filter used?

[Zane]

For 04 the 5.3L goes to 290hp and 330tq.

[Wayne2]

100R1 Posted on Jul 6 2003, 10:03 AM

  QUOTE (Tucson_02Silverado @ Jul 5 2003, 01:19 PM)

'02, No EGR, air box has no baffles like '01 (sshotrods.com), the throttle body and MAF look like 80mm 

 

 

What did GM do to lower the N0X levels with out a EGR valve?

Since no one is answering this one I'll refer to the LS1 and say they did it by changing the cam. I don't know when/how they did it on the 5.3 though.

[RyanbabZ71]

99 to 00 they changed the 5.3 cam to a 6.0 cam to up the HP from 270 to 285

[igbig]

I believe the 99s' had 275hp.

[Tucson_02Silverado]

02 uses the same air filter. Don't know if this is different from 99-01, but 02 5.3L is rated as ULEV (Ultra Low Emissions Vehicle). No I don't have CA emissions, standard federal emissions.

[MountaineerTom]

GM advertised the '99's as 270 HP and 315 TQ.

[Wayne2]

What is the difference between the regular air cleaner and the high performance cleaner that comes with the towing package?

[Tucson_02Silverado]

Don't know for sure. My 02 has the towing package and the stock filter is about 3" thick, but the base K&N part number since 99 fit just fine.

[woodrow]

i have heard the 2003 have 290 hp is this correct. and if this is true what did they do to make this happen because i would like to do it to my 01. thanks

[bigtruck21]

What is the difference between the regular air cleaner and the high performance cleaner that comes with the towing package?

It's called the high capacity air cleaner. I believe it's because the filter element is much deeper (more pleats or fins) than a standard filter. It's almost 3 inches thick compared to a normal paper filter of around an inch or 1.5. If you would stretch it totally and lay the paper flat, it would be longer. It just means it can hold more dirt and go longer between changes. I have almost 12k on mine and i'm suprised that the headloss guage has barely started to move, and I haven't lost any gas mileage yet. I haven't decided on which cold air intake I want to go with yet.