maf screen

Are you saying your AF ratio was 14.2 at WOT? If thats the case then yes thats severe! Put the screen back in! But if you are talking about it being that at part throttle when you are a hair on the rich side.

Chris

Yes that's at WOT. I can't put it back in it's long gone.

I have heard that the screen is to "smooth" the airflow through the MAF. If the screen is out i guess it "swirls" through the MAF and causes an inaccurate reading.

I pulled the screen out of my vortec 350 and bored the casing out to 75mm. I also cut the MAF supports off so it only has vertical supports. This is pretty much the same as the GMS MAF now. I never ran lean, in fact it helped out with the NOS. As far as the GenIII motors go, I don't know so listen to these guys since they have more experience. I agree the screen is for directing flow because of the honeycomb direction. I guess I was lucky LOL

OK so I lied! I went and looked through the pile of parts left over from my swap and there it was, moderately damaged. I was able to reinstall it with the old maf ends and I went and drove the truck, hard to tell if it made any difference performance wise but it started and ran good and smooth(no cycling like their was avacuum leak like before). I think I'll drive it around for a couple of days and check my plugs. I checked my plugs after a few K-miles with it descreened and they were super clean not lean looking just super clean almost new looking.

yeah checking plugs is a good way to tell about your A/F mixture and if its burning cleanly or not.

Chris