Buddy brought me a truck with a cam only tr220 5.3. First drive by cable truck I've messed with idle tuning on. Downloaded s tune from hptuners repository and copied to RAF, be, and timing tables as a base tune to start from.

I was getting weird numbers from running the Russ k idle configuration. It would show .3 lbs/hr for the warmer cells in the RAF. Checked the iac position and it was zero.

Did some reading and air has to be coming in from somewhere. Anyone have any ideas? I will also upload a picture of the throttle body. It kind of looks like it has drilled to me, but I'm not too familiar with these throttle bodies.

 

Ya, someone drilled it. There is no reason that TB should be drilled with a cam that small. On some VERY large cams it gets done but there is no reason to do it on that setup. Thats most likely where you air is coming in from..

 

I wasn't sure if that was a factory hole or not. It didn't appear to be threaded for anything to screw into it.

 

That hole is factory.

 

Bahaha this thread sucks

 

It looks like a Rough hole, and its factory? Wonder why some Cable driven are drilled and others are not? I know not all of them are drilled as I just worked on a 02 Tahoe that was not.

 

When GM switched away from using PCV valves to the fixed oriface design, the kit came with a little neoprene plug for that hole. Are you running a PCV valve or the fixed oriface in the left valve cover?

 

Don't make me go out in the garage and take apart the wife's Yukon while I'm trying to drink beer!


It's stock.

 

Ohhh, that makes sense.

 

Did not even think to check. I can check tomorrow. The motor has been switched out and I am not sure what the motor came out of. Stock one had a bad cam bearing. The next one was a junkyard special with a sticky injector that hydro locked. This is the third motor in it. Kinda feel bad for the guy.