Too bad there are many cars running Shaner throttle bodies with no ill effects.

For the MAF, as I said let a tune take care of it. You don't need to go in with a wide band sensor and recalibrate it from this alone. If this was such a MUST DO there wouldn't be so many untuned cars running LS6 intakes, ported TB's, headers, !converters, catbacks and even cams.

 

I never said the car won't run. It will. All I'm saying is, it won't perform optimally. The PCM will compensate for mods by adding fuel through LTFT's (long term fuel trims). It learns these based on feedback from the O2 sensors. Only problem is, the O2 sensors are narrowband sensors. They're only good for detecting a small region around a 14.7 AFR. So, if you have positive LTFT's when cruising, the computer assumes you will be equally lean at WOT. Unfortunately, many times this is not the case. Those who choose to run cams untuned face the possibility that they are running lean and we see it all the time over on LS1Tech. "Was on the dyno and saw 13.9 AFR!" As for this thread, I stand by the message that filling that hole with compound isn't the right thing to do in my opinion. People do run into problems with them. Not everyone obviously, but who's to say he won't?

 

My oppinion: Fill some of it but with much larger openings than the other people fill in. I left mine empty though, because I dont want the possibility of having a problem.

 

of course you use tune software/hardware with a wideband sensor. thats a given. You cant just recalibrate the maf with Just a wideband sensor, you have to have software/hardware to tune correctly.
The car comes stock running rich in PE. After I ported my MAF, I was running HIGH HIGH AFRs like 18.0:1 or 19.0:1 or maybe worse! The AEM only goes to 18s

 

Until they put a cam in and can't get it to idle right and start drilling holes in the throttle plate.
Took mine to have it dyno tuned and the tech was having trouble getting it to idle. He looked at me and asked if I had a ported throttle body, I said yes, why do you ask? He said take it off and I'll show you something. I climbed up on the dyno platform and removed the TB and handed it to him. He took a die grinder and removed all of the fill and cleaned it up back to stock in the area of the IAC ports. He said ok put it back on and I did. After I was done he reached in thru the window of the car and hit the key. It started right up and sat there idling as nice as could be. The IAC can NOT work properly without access to the proper amount of air.

 

Amen to this. Mine was tuned "mailorder style" using the LTFTs from AutoTap logs files and it ran great after 2 or 3 attempts we got the LTFTs to stay around 0. When I finally got a dyno tune and did the before pulls with a wide band we saw that the AFR was a steady 13.5 at WOT. Damn I could have ruined my motor running that lean. Just lucky I guess. I will NOT make that mistake again.

 

Again, I've seen many cars with Shaner TB's and cams etc. They don't have this problem. 1 that I know of is also spraying. Not to mention a close friend of mine who has a home ported TB done like this who is running a head/cam combo and no problems.