LS6 Intake Swap



after doing some research and seeing numerous n/a 5.3's and 6L hp flatlineing around 5800 and slowly falling after 6k, i decided to take the plunge and do the ls6 intake swap. the ls6 intake seems to be a proven performed intake that pulls all the way to 6500 in modified engines (ei full boltons, cam, etc...)

stuff you will need to get the job done:

a nice set of various ratchets, sockets, wrenches, etc...
4" electric grinder. (grinding discs/ cutting discs)
fuel line disconnect tool
big 3 jaw puller
1.5 ft of 5/16" & 3/8" fuel line
1 5/16" & 1 3/8" barbed fuel line fitting
6 hose clamps for the hose sizes above
1/8" / barbed fitting
small diameter vacuume line
gallon anti freeze

parts for the job:

ls6 intake
ls1/ls6 intake bolts (can't use the truck ones, they are too short)
97/98 vette fuel rail (for 99 to 03 trucks) or 98 to 02 f body fuel rail (04 & up)
ls1/ls6 style injectors (i chose 28.8#'s b/c i needed bigger ones already)
ls1/ls6 injector pigtails summit part no. MSD-2400
ls1/ls6 water pump
ls1/ls6 map sensor
custom idler pulley relocation bracket

about to get started...


removed the truck intake. alternator and p/s bracket removed also.

the fuel rail feed and return line will not clear the coil packs.
action: bend the lines upward to where there is enough clearance

notice how the fuel rail lines clear the coils
the coolant hard line nipple, needs to be bent out to clear the intake also

alternator and p/s bracket has to be cut in order to clear the throttle body since the ls6 intake sits alot lower than the truck one


the bottom of the tb needs to be grinded some in order to clear the top of the water pump.

new injector pigtails wired up. fuel pressure regulator line goes to small nip in back of the intake.

pcv line goes to the small nip in the back of the intake also. barbed fuel line fittings are used to connect the fuel lines. evap sensor tucked behind the alternator (use a vacuum line to connect it to the front drivers side nip on the intake)

since this intake was originally equipped with a cable style tb, i had to drill and tap for 1/8"npt / barbed fitting to hook up the passenger side valve cover vacuum line. also notice the black vacuum cap i plugged onto the intake.

final product


if you see anything out of place or think more stuff needs to be added, just put in your input.

engine idle


Enjoy