BIG JOE said:
What Hoss 350 sez. (and welcome aboard Hoss). I, like CSIPSD's, have my EBPV wired to be used as a engine brake.... Not near as effective as an exhaust brake (but a helluva lot cheaper) but it does give me just the right amount of brakeing help going down hill. I use it alot. Wired the way I have, it does'nt function as a Warm Up thingy at all. Completely controled by a switch on my gear shift. If I want to use it for a faster warm up, I can just flip the switch.
Insted of gut'n my wastegate, I went for a Big Head actuater, till I git over 100K... anyway
. Warrenty issues.
JOE
The exhaust brake mod for your EBPV is really neat. What you said about it not being quite as good as a true aftermarket valve is correct. The EBPV controls backpressure by having a big hole in the middle of it. This means your RPMS have to be up quite a bit for it to provide much braking. Aftermarket EB's have varying ways of doing the same thing, but are more sophisticated about it, and control backpressure to provide better braking at lower RPMs.
That having been said, I did the EBPV mod on my truck too, and LOVE IT. While it may not necessarily SLOW the truck on every hill, what it does do is hold it at a steady speed instead of allowing it to run off down the hill. You don't have to use your service brakes hardly at all even on the steepest of hills with the heaviest of loads.
To those that asked, you can do the mod the way Joe did it by simply finding the wires that come out of the EBPV (at the base of the turbo pedestal, at the front). There are two wires for the EBPV, IIRC one is solid black, one is grey w/ black tracer. Cut the Grey wire and wire it to a switch that supplies 12V hot power fromt he battery. When you flip it on, the EBPV turns on, and voila! you have braking. I also use mine in conjuction with my homemade high-idle function to run my idle up to 1200 RPM, then close the EBPV to put it under load. That way, in the morning, it heats up FAST. In something like 5 min I had warm air at the vents in 15 F weather. It rocks.
To those that still want the EBPV to function the way the factory intended, but still want to use it as an exhaust brake, the task is only slightly more difficult. Just go get a couple rectifier diodes (electrical check valves) from Radio Shack. Cut the Grey wire, and soldier one diode to the PCM side of the wire, directed so that it prevents current from flowing TOWARDS the PCM. This keeps the PCM from getting a 12V hot signal when you manually operate the EBPV. Then take the other diode and soldier it to the wire from your switch, so that it prevent s current from flowing TOWARDS the switch. This keeps your switch from getting 12V hot when the PCM decides to turn ont he valve. Then, connect the other ends of BOTH diodes to the EBPV side of the grey wire. Run a hot 12V to your switch, and you have a EBPV that functions like fromt eh factory, but can also be manually turned on.
Welcome aboard Hoss 
