[Formulajones]

I switched the Chevelle over to fixed orifice PCV, after I had run the Sniper setup for more than a year with a regular PCV.

On mine, going to a fixed orifice, basically made the vacuum leak much smaller and caused the IAC counts to rise a bit to bring the idle back up where it was commanding. Once warmed up it's not a big deal but when it's cold it really tightened up the window I had for a high speed cold idle, basically pegging the IAC at 100 when cold to barely maintain an idle.

What it boils down to for me, and something I complained about very early on when we bought these Snipers, is that the IAC could stand to be a bit bigger for these larger engines with big camshafts that have a bunch of overlap.

I've played around with drilling the fixed orifice, I think I'm up to 3/32" or so and it hasn't really made a bunch of difference. Of course that's not even close to the near 1/4" or 5/16 hole the regular PCV had, LOL

Funny this all came up because I was going to switch it back over to the regular PCV today. I never had any drivability or running issues with it so not sure why they preach that so much over on the Holley forum.

The GTO got switched over to a vacuum pump so the engine is totally sealed, eliminating the PCV. But that was done for other reasons.