I have been contemplating about buying the same cam. Scream...where does the power seem to kick in? Did you lose any low-end? Do you currently have a stall? How does it sound/lope?

 

I don't have a converter. I'm going to get the truck on the dyno one afternoon this week, but I don't really think that I lost anything down low. The truck feels much better at part-throttle, but really pulls strong from about 3500 straight to redline.

The cam is actually a little too much for a 4.8 with no tuning IMO. I don't really wanna mess with the TB to get it to idle correctly. I'm sure that some (if not most) people would be content with a little idling trouble, but I'm not. I want it to idle and drive like it should--and right now, it's not. Maybe it's because it's a 4.8, though.

All in all, I'm VERY impressed with the power, but I'm not really happy with the driveability issues that I'm having. Guess that I'm just gonna have to quit bitching and get EDIT...and, a laptop!

 

The longer you drive this cam the better it will get. I pissed when I first installed my cam. By the next day it had gotten better. It also feels like the power will increase the longer you drive it. The less backpressure the exhaust has the worse the idle. Good luck.

 

If you go into Autotap, look up your IAC counts.

If the truck won't hold an idle, there's a good chance your IAC counts are over a 100. I think at 125 it maxes out. stock counts should be around 30 I think.

An easy reversible way to play with it is to adjust the idle set screw. I think it's a torx 10 or 15.

Or, stuff a rag behind the TB blade, and then drill out the air hole... Use the rag to catch shavings, and then pull the rag out...

Try one size bigger and see how you like it...

 

I borrowed a friend of mine's Scanmaster, and my IAC's are around 50-60 in neutral or in gear. I'm beginning to think that there may be another problem, like fouled plugs or a bad plug wire or something.

Is there anyone else who has installed this cam in a 4.8, or even a 5.3? Any idling issues? I swear that there is an off-idle miss, but everyone that listens to the truck says that it's just the cam loping.

Yesterday, the truck ran better. This morning, it was very bitchy in traffic. I just can't figure it out.

 

Does it lope and shake quite a bit?

Maybe you are running on 6 or 7 cylinders?

Did you autotap misfires?

 

It will feel like it has a miss but, it does not. Once the idle starts to surge and idle stupid it is hard to calm down. In my old 5.3 I set my idle at 800 and opened the TB blade, it seemed to fix alot of this. I remember having to drive two footed in parking lots.
You need a programmer the missfire codes will disable the torque converter. If you have a stall it will get annoying on the highway.
Good luck.

 

Man Mine did the same thing for a while and still does one and a while. If the humidity is high it seems to do it even worse for some reason. Give it a bit of time. I have heard of these acting crazy up to 400 miles. Until you get it tuned it wont act like it really should. Damn I cant wait for my programmer to get back from diablo

 

I was getting misfires on every cylinder, I think like 20-30 seems to be the number that I remember. I went with the TR55's, but my buddy that helped with the cam suggested TR6's. I'm getting new Taylor wires today and I'm going to pull the plugs tonight.

But, there is a bright side to this story. We messed with the adjustment screw on the TB last night, and the truck will crank and idle all by istelf!!!! The truck doesn't seem to want to come down in revs when braking, but it's not too terrible bad. The truck sounds badass idling at about 600-650 rpms. Just enough lope to tell that it's got something!

Oh, anyone know how to clear the DTC's with a Scanmaster?