Im still working the idle in my tahoe, it is getting a lot better but I have some random dieing going on here and there and some slight bucking in 3rd with the Tcc locked. My idle air flow log says it wants 16.xx g/s for idle in gear. This gives me 15% throttle at idle. It's DBW. I loged STIT today and the most it tried to pull was 10lbhr but for the most part just 1-2lbhr which is very little when converted to g/s. I'm wondering what you guys with bigger cams get for RAF.

 

You want to compare desired idle air to the values in the RAF. The STIT tries to go to the desired value within its limits.

 

That's what I'm doing and it wants 16.xx desired some times a little higher for fans. But is 15% TPS acceptable? The STIT are plus or minus 1-2lbhr once warm with fans off. But yet the iac count stays at 310. I'm guessing because it's DBW but I don't know. It never changes.

 

I think mine was around 8% when I had DBW but a lot depends on your cam and idle rpm.

 

227/235 111lsa in an all stock l92. 9° of overlap at .050" idle is at 750rpm.

 

My guess is that idle is a little low. See if 850 is more stable.

 

Well it likes to idle lean for sure. Get into the 14's and its a little crazy mid 15's and it just lopes along no problem. I dropped some timing also, didn't loose any vacuum doing so and it seems more stable. But since it idles at 15% throttle I get bucking in that area with Tcc locked at low speeds. I need to figure out how to adjust the follower to stop this.

 

Mine is around 10%.

700-725 idle.



What make you choose that cam for boost?

 

Everybody said not to. And yet it spools super fast, runs hard, and pulls to 6200 or so. One big reason I did it was to lower dynamic compression some. Another was because I knew NA this cam would have good low end torque while being able to pull a decent rpm. It does everything I wanted it to do and then some. The best part is how fast it comes up on boost. I'm in boost before I'm on top of the converter. Which makes tuning the VE table a little awkward, when I let off it tends to back track and change the VE requirements. It took me a couple times to realize what was happening.

 

As long as you're happy with it, that's all that counts.