mitchellmade

iTrader: (13)

Picking apart an 08 sierra 4.8 wondering if that intake and 799 casting heads are worth buying the engine and harness for $800 to improve my 99 5.3 ecsb

1Bear

iTrader: (1)

They are worth getting if you can pick them up for the right price. Yes they can add power to your engine, but you will have a couple of hurdles to clear to get everything working. As far as I’m aware, the newer 5.3’s have flat-top pistons, so unless you have the heads milled to get the compression back up, it will be counter-productive. You will need to factor in a cable operated 90mm throttle-body or run a 90mm to 78mm adapter to use your current unit. The fuel rails on the ’08 model intake are set up for a returnless system, whereas yours are return style and you would need to address this as well, but there are solutions to everything one of the hurdles I just mentioned.

mitchellmade

iTrader: (13)

Is there a factory 90 mm cable operated throttle body I can use? Also I can use a vette fuel filter right, do I have to change my fuel pump?