Remember "Guidelines" have "Default" settings....

All the buff magazines tech articles and a lot of the "How To" books-i.e.-"How to Hotrod Small-Block Chevys" "How to build Max Performance Mopar V8s" "How to Build Big-Block Fords", etc, etc use general guidelines on their advice. You have to realize that for the industry as a whole the default test mule is a small-block Chevy. So a "rule of thumb" when choosing a cam, header tube size, a carb and intake, whatever is geared toward a 350 Chevy. And not an 11:1, 370 hp fire-breathing LT1. The industry "test mule" is the 8.5:1 L48 350 that powered millions of cars and trucks in the '70's and '80's and is still being sold as a base-model GMPP crate engine to this day. It has about 200 hp and 280 lbs ft of torque. So if your building a 460 Ford or 455 Pontiac or 440 Mopar-using the "basic" guidelines are going to be very conservative-probably too conservative to get the best performance out of the larger engine.  Here's some myths that definitely need "busting".  # 1. A single 4bbl on a dual-plane intake is the only way to fly. This is a falsehood that's been perpetuated for 50 years. Tri-power 389 and 421 Pontiacs, 427 'Vettes, Six-Pack Mopars, 409 Impalas, 426 Hemis, 427 Fords, all absolutely rock with multi-carb setups, if their tuned right. Edelbrocks Performer RPM dual-quad setup made MORE hp and torque-over 600 hp-on a ZZ502 crate engine-more than their vaunted Performer RPM and Victor intakes!!  Ferarris, Porsches, Lamborghinis and other exotic sports cars had multiple carbs for years. I helped tune a "truck pull" champion a few years ago. It was a Chevy pickup with an alchohol-burning 454 with 4 Webers on it. It smote all comers in biblical fashion, including a Dodge with a blown Hemi in it!!  Manufacturers went to single carbs and later fuel injection because of stiffening federal emission laws and fuel economy guidelines, not lack of perfromance!!  The buff magazines have been saying a single 4bbl is the way to go for 50 years because of ease of tuning, and the ability to make them pretty much idiot-proof.  Like I said in a previous post-some clown buys a Six-Pack Super Bee or whatever-and the second it fouls a spark plug he starts screwing around with the carburators. Pretty soon it won't even start, much less run properly. If you want the look and sound of a multi-carb setup,especially on a big-block-like a 454 Chevy or even a 400 Pontiac or 383 Mopar-dual-quads will rock if their jetted properly. As for single-plane intakes-they generally make power higher up in the rpm band at the expense of bottom-end torque. So yes-putting a Torker II or Victor Jr. on that L48 350-that loses 30 lbs of torque at low speed- when you only had 280 lbs at the absolute peak-will absolutely kill the performance. However putting a Torker on a 455 Pontiac that makes 500 lbs ft at 2,700 rpm-even if you lose 30 lbs-you still have 470 lbs of tire-frying torque!!  You won't notice any difference in the bottom-end, but the mid-range and top-end will hit like "gangbusters". That Victor Jr that killed the 8.5:1 L48?  Guess what?  On an 11:1 383 it'll make more power ALL through the range, even topping a dual-plane Performer at the low end!!  Even on a 9:1 '79 L82 350 Corvette with a 4-speed and 3.70:1 gears-you'd get better performance from a Torker II or a Weiand Team G than you would a Performer. Because the L82 has the heads and the cam and the gears to use the boost from 2,800-6,500 rpm. The L48 with it's lazy cam and probably 2.73:1 gears behind a TH350 wouldn't do well. See what I'm saying?  # 2. We Shall Overcam. Again-most of the "Guidelines" you see on cam recommendation is based on the ubiquitous SBC. So yes-a cam with 234 ( @ .050 ) duration and .470  lift is going to have a lumpy idle  in a 350 Chevy and need a stick or a 2,500 rpm converter and 3.73:1 gears to work properly. A cam with 232 / 232 duration and .475 lift will idle smooth and work with a stock torque converter and 3.08:1 gears in a 455 Olds!  ( I know, that's the stock cam my 442 had! )  Larger engines can take more "cam" without ill effects-because they have more bottom-end and mid-range torque to start with. Manual transmission cars can tolerate more "cam" than automatics because engine vacuum isn't as important ( most automatics have a vacuum operated modulator that controls shifting. ) and the driver can launch at whatever rpm he desires by manipulating the clutch. Here's a good example. The old standby-the L79 350 hp 327 Corvette cams. It has 224 / 224 ( @.050 ) duration and .447 lift. Even with a stick, this cam would absolutely kill a 305. It will work pretty good in a 327 with a 4-speed and 3.70:1 or stiffer gears. It will be even better in a 350 with a 4-speed or an automatic with a 2,000 rpm converter and 3.31:1 or stiffer gears. It would be really sweet in a 383 / 400 even with a stock torque converter and 3.08:1 gears. So remember-if your building a 460 Ford-what Crane or Edelbrock or Lunati says is a "mild" cam-will look gargantuan compared to the guidelines for a 302 or a 351W!!  Get the concept?  # 3. Gears make it go. Up to a point. Then you hit the wall of diminishing returns. For example if you have a "Smokey & The Bandit" '77 T/A with a 400 Pontiac / Th350 combo with 2.56:1 rear end gears-swapping to something in the 3.23:1-3.42:1 range will give you a huge boost in performance-drop your 0-60 and 1/4 mile time by 1/2 a second or more without hurting freeway cruising rpm or drivability too much. So if 3.42:1s are good, wouldn't 4.33:1s be awesome?  No!!  Here's why. 1st off-the stock L78 400-while having a lot of torque for a low-compression "smog" engine-is pretty much all done in by 5,000 rpm. With the 4.33:1 gears you'd literally run out of rpm before the end of the 1/4 mile!!  And having the motor buzzing at 3,800 rpm at 65 mph on the freeway wouldn't really be a pleasant driving experience!!  Especially with big blocks-gearing isn't as important as people would have you think. I swapped the 3.08:1 gears in my Hurst / Olds for some 4.10:1s figuring it would make it really a rocket off the line. You know what's funny? The car wasn't one iota faster in low gear. My 60 ft time didn't change one ounce. It was however noticeably faster in the 1/4 and MUCH stronger on the top-end in 2nd and 3rd, due to the extra torque multiplication! Huh?  That's because the 455 had enough torque to launch the car quickly even with the 3.08:1s. And the 4.10:1s only worked because the 455 had a hot Lunati cam, headers and an Edelbrock Torker intake and I shifted it at 6,200 rpm ( 1-2 ) and 6,500 rpm ( 2-3 ). If the engine had been stock-where it had massive torque but was all done in by 5,200 rpm-like I said I'd have run out of rpm before the end of the 1/4.  Gears mainly help small engines-a 302 Ford, a 327 Chevy a 340 Mopar-these high winding engines are going to do better with 3.91:1 or 4.30:1 gears than say a 440 or a 454 or a 460. I know a guy who built a mega-torque 454 for his '74 Chevelle Laguna. The car ran 12.80s with 2.73:1 gears. Pretty impressive. He figured hell-I swap in some 3.73:1s and break into the high 11s easily. He swapped the gears and the car was faster, but not much. With the 3.73:1s it only ran 12.40s. He hit the point of diminishing returns. Yes, he could have hit the 11s-but he'd have needed a bigger cam, a higher stall speed converter, maybe a bigger carb and intake-which would have ruined the cars drivability and idle quality. What made it so cool was it purred like a kitten-till you hit the loud pedal-and then "Dr Jekyll" turned into "Mr Hyde!".  To get to the 11s he'd have had to live with "Mr Hyde" all the time!  Which he didn't want. He switched back to the 2.73:1s because he liked the top-end on the highway and the relaxed cruising at 65-75 mph. So be careful, and try to err on the side of caution-but remember-"basic" guidelines are always set for a stock small-block Chevy!!  Hope this helps everyone out. Mastermind