I agree, there should be more vacuum with a (relatively) small cam in a 440. The 272@.050 cam in my 451 pulls 8" at idle!
Also, forget you ever heard that "PV needs to be half the idle vacuum". Holley just told people that to give them a starting point but it's rarely correct except for stock...
Today I saw another article on this issue... apparently when reflashed, the ECU writes a tamper code to the body control module (which I guess the tuner didn't know about, or care). Anyway the car owner went as high as VP level and was shut down every time, so now he's pulled his posts and...
Drove 42 miles to Mountain Home for a cruise-in/car show despite the showers forecast. Fortunately they were wrong and it was sunny, but 90F and humid makes for a hot day on a black asphalt parking lot. Free grilled hot dogs and a door prize too :) The Murphy/Walmart gas station next door had...
No one has mentioned yet that the bolt holes on stock heads aren't drilled perpendicular to the rails. That's what makes it so hard to get any gasket to seal well regardless of what kind of cover.
From the article, the manufacturer has a different story:
"He says the mid-muffler and entire emissions system are stock. But this is where things start to get confusing. You see, Dodge says this isn’t about the mid-muffler. Dodge says, “The warranty claim was rejected after a Stellantis...
I don't recall ever seeing (or hearing) about the possibility either! Learn something new every day.
But I don't think it's happening simply because the 3000 rpm cruise AFR is over 15 with #71 primary jets (and #86 secondary which do not appear to be in play)...
Let me know what you find out!
I think your memory matches mine (holes in line with the t-slot)... I bought the carb with the holes from Brad Haak, who knows a thing or two about Holley setup ;)
Interesting idea, thanks! I hadn't thought about that possibility... but is that quantity of air really that substantial through .100 holes at 15" vacuum? The primary throttles are open further, at highway cruise, so I would think almost all the airflow would be going through those bores as...