Thanks for moving this thread Chad! Now we got everything in it's proper place.
And for proper identification, the intake manifold in Chad's pic is an aluminum casting, "rpt" intake. Those are based upon the "last gen" cast iron intake manifolds ihc produced but have been enhanced somewhat. But the cylinder runners are exactly the same as any other IH-produced manifold, though the one in the pic is a 4 venturi/barrel unit.
I was gonna hold off on posting this response until the subject was appropriate, but I think now is the proper time. Travis is in "learning mode" and we don't wanna miss an educational opportunity. I'm a bit concerned that the following May confuse the issue but it does go hand-in-hand with the subject of "firing order" for the sv engines.
We've previously defined the cylinder numbering sequence, along with the ignition/cylinder firing order.
Many times...ignition problems are blamed for drivability issues, when in actuality, the fuel/intake system can be the fault, most especially the carburetor.
All sv engines use either a 2v (2 venturi or "barrel") carburetor, or a 4v (4 venturi/barrel) carb as oem equipment. No sv engine was ever supplied oem with a Holley "3v/barrel" carb.
A 4v carb is basically the same thing as a 2v carb with two additional venturis/throttle bores added, along with a "secondary" fuel reservoir and metering system.
The intake manifold for "most" (but not all) the sv motors is a variation on a "high-rise" design, with a dual plane casting. For purposes of this thread...it's only important to understand the following:
no matter if the intake manifold is a 2v or a 4v design, the passenger side venturi/plenum feeds cylinders #2, 3, 5, and 8. The driver side venturi/plenum feeds cylinders #1, 4, 6, and 7. Please note...this callout is not the same as "firing order"!!! It does not have to be! Look closely at the rpt intake manifold, you can easily see which runners feed which cylinders.
Comparing a 4v manifold with a 2v unit, we find that the "secondary (rear) throttle bores simply connect with the primary throttle bores, which allows an increase in atomized air/fuel volume when the throttle system opens past approximately the 2/3rds point in rotation, hopefully resulting in an increase in available engine horsepower/torque.
If...one side of either a 2v or 4v primary carb circuit should malfunction, the end result is gonna be four dead cylinders, the plugs will be firing, but because no fuel/air mixture entered the combustion chamber, there is no charge to fire at the appropriate time as determined by the ignition firing order.
This is a very important diagnostic technique to employ when trying to deal with cylinder misfire...either a single cylinder or multiple cylinders.
