Why do people mess with perfection?

Saw a musclecar shootout in a national magazine the other day that made my head want to explode. There was not one, but TWO 1973 Pontiac Trans-Ams competing, and both of them had modern fuel-injected Chevy LS7 motors in them and extensively modified suspensions. Forget the sentiment of butchering a classic, why couldn't these guys get one of the two million or so beater 70-81 Camaros and Firebirds out there and cut that up, yada,yada,yada. No, looking at it from a strictly engineering standpoint, performance level, and bang for the buck, these guys definitely fall into the more-money-than-brains category. Here's why-# 1. Handling. These cars were so awesome back in the day, and still have a fierce following, and are gaining new disciples from the younger generation every day. The reason is Herb Adams and company designed an excellent suspension all those years ago. Back when an F60-15 Firestone Wide Oval or Goodyear Polyglas GT bias-ply was the best street tire on the market, you had to design a suspension that kept the tire perpendicular to thye road under high-speed cornering load. In other words-the car was holding the tire on the road. Now, tire technology has come so far that lazy auto engineers are using the tire to hold the car on the road. That's why front-drive econoboxes can generate high skidpad numbers if their shod with low-profile performance tires. Here's some hard data to support this fact. Car Craft decided to build a G-body project car several years back. It was a generic 1984 305 Monte Carlo. They were going to swap in a killer 383 to make it fast, and they wanted it to handle.  It didn't have the handling suspension that Monte Carlo SS's or Buick Grand Nationals did. They tested it on the skidpad with the P195/75R14 tires it came with. It registered an abysmal .67g.  For comparison-an '80s S10 Blazer has better numbers than that. All they did was install some 16X8 wheels and P245/50ZR16 tires off another staffer's IROC-Z Camaro, and tested it again- for giggles and guess what- it recorded .80g!! A stunning improvement-just by changing the tires-no springs, or shocks, or sway bars, nothing. They were stoked. They knew with proper springs, shocks and sway bars, that they could get it up close to .90g-that's Corvette and Porsche territory-with a suspension that was designed in 1963. How does this pertain to the '70's T/As? Read on.  Road and Track tested a 2010 Camaro SS and a 2010 Challenger SRT8.  We all know the skidpad is the industry standard for measuring cornering prowess. The higher the number, the better handling the car. Anyhow-the Challenger SRT8 pulled .85g on the skidpad, shod with 245/45ZR20 Goodyear Eagle F1 tires. The Camaro SS pulled a slightly higher .88g running on 245/45ZR20 ( Front ) and 275/45ZR20 ( Rear ) Pirelli P-Zeros. Car and Driver's 1979 Trans-Am came very close-laying down .82g- on skinny, S-rated P225/70R15 Goodyear Polysteel Radials!!!  It doesn't take a mathematician to do this equation-With some modern, fat,ZR-Rated rubber, the old T/A would easily surpass both of them. This was borne out with another magazine's "Project G-28". They took a 1976 Camaro-added subframe connectors,upgraded front and rear sway bars, springs and shocks, and some fat, ZR-rated 18 inch rubber. They got it up to .95g on the skidpad-and that's a bunch. I mean that's ZR1 Corvette, Porsche 911, and Ferarri F430 territory. On a solid-axle suspension that Herb Adams designed in 1969. So why do these fools put aftermarket subframes and rack and pinions in these cars? Your going the improve the handling? How?  Ditto for the 9 inch Ford Rear ends. 1970's T/A's came stock with GM's excellent 8.5 inch ring gear 10 bolt positraction unit. And their tough. I have had 400, 4-speed T/A's that I drag raced and dropped the clutch on at 4,000 rpm for five years and never had a problem. And they just keep on working like the Energizer Bunny-I pushed my buddy's Camaro up a snowy hill he was sliding backward down to his house one winter day in my '77 T/A. That's how good they work.  Try to keep a straight face while telling me that that extra .5 inch on the ring gear makes all the difference in durability!  A new Currie 9 inch with GM mounting points costs $3,500!. Even if the stock rear needed rebuilding, you could get that done at any competent driveline shop for a lot less than $3,500!!  As for the engine-a 505 hp GM LS7  ( Z06 'Vette motor ) costs 18 grand from GMPP.  Mast Motorsports sells hot rod LS motors for around 12K on up. Then you have to wire it up.  1973 T/A's had 455 cubes under the hood stock. By simply adding Edelbrock Performer RPM heads, headers, the matching cam and Performer intake- at a cost of about 3 grand- you can make 460 hp and 440 lbs of torque-and that was on a 400 test mule. A 455 would be very close to 500 hp with the same equipment. Or for around $7,500 Jim Butler Performance will build you a 455 Pontiac guranteed to have 600 hp and run on 92 octane pump gas. That's a LOT cheaper than 12-18 grand for an LS engine, and the car runs just as fast. The same goes for transmissions. '73 T/A's either had a Muncie M21 4-speed or a TH400 automatic stock. Both bulletproof, and both will stand up to as much power and torque as your wallet will muster. So why do they need a 4 or 5 thousand dollar six-speed manual or overdrive automatic swap?  To me-500 less cruising rpm on the freeway is not worth 5 grand. For $2600 you can buy a Gear Vendors overdrive that stands up to Top Fuel drag engines and would turn your M21 or TH400 into an 8-speed or a 6-speed, for a lot less money.  I'm all for people improving the performance of their cars-"Dukes of Hazzard" and action movies aside-1960's Chargers handle like the average UPS truck in stock trim-so thank God for XV Motorsports and others that make Mopar handling parts. But since Herb Adam's brainstorm has been called by Car and Driver-"A lightning-reflexed commando of a car whose handling can't be matched by cars 5 times it's price" ( meaning Ferarris of the day ) why can't these idiot's leave well enough alone?  Mastermind