318 Four Barrel Intake

All good advise thus far, just thought I would chime in on the port mis-match. Way, way back when, 30 plus years ago, I read all the Mopar factory books (Hustle Stuff/Direct Connection) and thought what they said was gospel. They always said do not use 340 manifold on a 273/318 under any circumstance due to the severe port mis-match. SO, I spent big bucks (at the time over $300) for an Edelbrock Streetmaster 318 and AFB 500 carb. Worked great, went from a stock 17.4 et down to 16.2et. Very pleased untill I saw others with $15 junkyard 340 intakes (that was $15 for the intake and AVS or Thermoquad) on their otherwise stock 318's running deep into the 15's. They just shook their head at me for spending so much money. Also remember how the same books went into great detail describing the proper way to notch the bore so that a 273 could then be able to accept 340 heads. Many years later I found out, you can just bolt them on, "factory book" be damned. Through the years I found many other discrepancies from the factory experts (big block/hemi too), but those just starting out would correctly assume that the factory knows best. Haven't looked at one of those books in years. Sorry if I strayed a bit off topic but I still get mad every time I see the "port mis-match" mentioned.

Just remembered:::on my '81 Ram 360 I swapped out the original thermoquad and 4bbl intake for a stock 318 intake and 2bbl carb just to get better fuel mileage. Works great:::been on there for 17 years and guess what? "severe port mis-match" again.