[oxfordsteve]

I have a 99 K1500 4X4 suburban in excellent shape, but have had ongoing problems with the notorious vortec intake coolant leak and am fed up with the trouble and expense. I have a fresh 455 in the garage and wondered if it would be feasible to put it in the 'burban. I know I would have to get an adapter for the tranny, motor mounts exhaust etc but that is within my skills. What I don't know about is how to get around the computer, electronics, wiring, fuel injection etc and everything work and be driveable. I'm afraid it might be a pipe dream. Anybody done this swap? If not does anyone have a suggestion for a replacement motor that makes more power, directly bolts in and doesn't leak constantly?

[disc0monkey]

im pretty sure you can run the FMU from the vortec and hook up the sensors for the gauges, i probably would cut the circuit going to the check engine light so its not on. not really sure exactly if you can shut down the OBD.

[GOAT WAGON 428]

Good idea!
How much H.P/T.Q. does the 455 have?

[RamAirZ]

Originally Posted by disc0monkey

im pretty sure you can run the FMU from the vortec and hook up the sensors for the gauges, i probably would cut the circuit going to the check engine light so its not on. not really sure exactly if you can shut down the OBD.

FMU? I have a 1998 Sierra 1500 Z71, it is feasable but your problem is going to be the transmission/transfercase for the 4wd. If you have the Vortec 5.7 that I think you do (like in my truck) it is an awesome engine for the most part but blows when it comes to modifying it and when it starts having problems. The Factory intake manifold uses a spider-style injector setup. 8 tiny injectors fed by a fuel block mounted in the intake manifold. The fuel lines plumb into the manifold. You never see the injectors. Also, there is a main block from the wiring harness that plugs into the top of the fuel block to run the distribution of each injector. You won't be able to swap any of this stuff over seeing as the way this motor runs is all based inside the manifold (which of course won't swap onto a 455). Our computer system sucks too, Tunercat was the only thing on the market available to "tune" our engines, now they sold out to JET performance but it is still the only program out there. You could modify the factory engine harness that plugs into the fuel block to hook up to 8 seperate injectors. Like this The manifold on the left is a marine manifold found on boat engines which uses EV1 injectors (actually EV6 but same dimensions), commonly found on anything with fuel injection (camaro, firebird, some mustangs, etc). I have all the wiring schematics for our intake system. You could drill 8 injector holes into your Pontiac manifold, get aftermarket fuelrails, plumb some AN line from your factory fuel lines, wire the injectors up into your factory harness like the picture, and find someone to make a plate to bolt your Vortec TB to the Pontiac manifold if you wanted this to all run off your factory computer, and of course get the JET tuning software and have it tuned for the new engine. But you could always run a carb, switch to a 700R4 4wd transmission (non-electronic but same dimensions and will bolt to your transfer case), and leave your factory computer plugged in to keep your auto-shift transfer case operational. Or spend $650 bucks on the 4L60E Tcom software program from TCI to run your 4L60E with your new 455. K I'm finished now lol. If you have anymore questions about your Vortec engine shoot me a PM, I've been inside and out of this thing when I was building my truck to run 12's when it had the blower on it lol.

[RamAirZ]

Try this site- http://www.intakeelbows.com/ You could probably use a LS1 style throttle body and the TPS sensor and everything should plug up from your factory one. Use one of those elbows, injector bungs etc