This is part project blog, part help line for whatever questions arise. No pics yet, will post some eventually.
New to the project inventory is an 04 Sierra 2500HD RCLB 4x4 w/ LS2 and 6" BDS lift. it's dented, rusty, missing seats, needs tires, the brake lines rotted away, rotors and pads are shot, and the exhaust from the cats back is long gone. The LS2 is an 05 GTO long block with the truck's original LQ4 top end, manifolds, and front drive accessories swapped over. I got it in non-running condition and was told the engine could be locked up. I'm undecided on a clear plan for this thing, though am currently working on getting the engine sorted out before firing the parts cannon at it.
I pulled the plugs, removed the drive belt, and was able to spin the engine and accessories by hand. After rigging up a battery the starter solenoid was discovered in-op. I paid $45 for a junkyard starter and was able to start the truck. It idled rough and had good oil pressure according to the stock gauge. What fuel is left in the tank is of unknown age and octane.
First order of business is to get the engine to idle smoothly. I cleaned out the packed K&N filter, replaced the failed MAF sensor, cleaned out the throttle body, installed new GTO-spec AC Delco plugs, new MSD plug wires that came with the truck, and installed a new battery. I verified spark on each cylinder, but the idle is rough. Throttle response is improved, but the idle roughness shakes the truck.
I'm now on the path of vetting the fuel delivery system. According to Googles, the compression ratio of the original LQ4 is 8.4:1 and uses 24# injectors, where the LS2 is 10.9:1 and uses 34# injectors. The injectors in the rail are original to the truck, so 24#. I'm somewhat certain the truck has not been tuned for the engine. Up next is adding a few gallons of 93 octane to the tank and see if any improvements are made, and listening to each injector for a click. A cylinder leakdown and compression test are in the future, too. If significant improvements aren't made, then I'm probably going to swap injectors and phone-a-friend for a tune.
Long wind-up to a Tuesday question. . . What do y'all recommend for an decent but economical set of ~34# injectors, and adapter harnesses if necessary, for the 04 LQ4 fuel rail?
New to the project inventory is an 04 Sierra 2500HD RCLB 4x4 w/ LS2 and 6" BDS lift. it's dented, rusty, missing seats, needs tires, the brake lines rotted away, rotors and pads are shot, and the exhaust from the cats back is long gone. The LS2 is an 05 GTO long block with the truck's original LQ4 top end, manifolds, and front drive accessories swapped over. I got it in non-running condition and was told the engine could be locked up. I'm undecided on a clear plan for this thing, though am currently working on getting the engine sorted out before firing the parts cannon at it.
I pulled the plugs, removed the drive belt, and was able to spin the engine and accessories by hand. After rigging up a battery the starter solenoid was discovered in-op. I paid $45 for a junkyard starter and was able to start the truck. It idled rough and had good oil pressure according to the stock gauge. What fuel is left in the tank is of unknown age and octane.
First order of business is to get the engine to idle smoothly. I cleaned out the packed K&N filter, replaced the failed MAF sensor, cleaned out the throttle body, installed new GTO-spec AC Delco plugs, new MSD plug wires that came with the truck, and installed a new battery. I verified spark on each cylinder, but the idle is rough. Throttle response is improved, but the idle roughness shakes the truck.
I'm now on the path of vetting the fuel delivery system. According to Googles, the compression ratio of the original LQ4 is 8.4:1 and uses 24# injectors, where the LS2 is 10.9:1 and uses 34# injectors. The injectors in the rail are original to the truck, so 24#. I'm somewhat certain the truck has not been tuned for the engine. Up next is adding a few gallons of 93 octane to the tank and see if any improvements are made, and listening to each injector for a click. A cylinder leakdown and compression test are in the future, too. If significant improvements aren't made, then I'm probably going to swap injectors and phone-a-friend for a tune.
Long wind-up to a Tuesday question. . . What do y'all recommend for an decent but economical set of ~34# injectors, and adapter harnesses if necessary, for the 04 LQ4 fuel rail?
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