More on the point of diminishing returns...

In the last post I talked about the point of diminishing returns. Here's some more examples of people searching for the "last ounce" of performance that it backfired on. I may have touched on these before but their worth re-visiting. A guy I knew had an '81 Trans-Am that had a 305 Chevy V8 and a 4-speed. The first thing he did was swap in a stompin' 350. Nothing wrong with that-that's exactly what I'd have done. Then he got some 17" Snowflake wheels from Year One and some 275 / 40ZR17 BFG Comp T/A tires. That would have been my next move. Then he went overboard. He installed a roll cage and subframe connectors and braced the front subframe to the firewall, and then installed solid bushings throughout the suspension. The car went faster than a Porsche 911 Turbo around Reno-Fernley Raceway. However, on anything but glass-smooth pavement it was undrivable. Every little ripple, every little bump was transferred to the drivers seat or the steering wheel with bone-jarring force. I mean you'd piss your pants in a mile because it jarred your kidneys so much! Now if he'd gone with urethane bushings instead of aluminum, it might have been a little stiff, but it wouldn't have rattled your fillings loose! He sold the car to a guy who made it into a race car-because you couldn't drive it on the street without beating your brains out. And the guy who made it a race car put rubber and urethane bushings back in it, so it wouldn't beat him to death on the track!  I also talked before about a guy who had a '74 Malibu with a strong 454 in it. The car ran 12.80's with 2.73:1 gears. He figured he'd swap in some 4.11:1s and run low 12s or high 11s. He was severely disappointed when after changing the gears the car only ran 12.40s. Further-now instead of easily cruising at 2,500 rpm or so at 75 on the freeway and having major top-end speed-5,500 rpm with the 2.73:1 gears was something like 143 mph-now the motor was buzzing at 3,500 rpm on the freeway and the top-end was all done in by like 115!!  How can this be? Well, for one thing-because he had the 2.73:1 gears-the guy who built his engine built it for max torque. When you've got 500+ lb ft of torque right off idle, you don't need to rev to 6,500 or 7 grand. So the 4.11:1 gears didn't help that much because the car had enough torque to launch the car with alarcity in low gear regardless of gearing, but because his cam and carb and intake and everything else was geared to make maximum low-end and mid-range torque, he ran out of rpm toward the end of the 1/4. And that's why his top speed was so diminished. To go 140 mph with 4.11:1s the engine would have turn about 7,000 instead of 5,500, and his combo wasn't set up for that. So now he faced a real dilemna. To get the 1/4 mile speed he wanted, and to take full advantage of the 4.11:1 gearing he'd need a bigger cam. But, going to a bigger cam that would allow him to make power to 7 grand, would mean he'd need a higher stall speed torque converter, and would be giving up quite a bit of idle quality and low-end and mid-range torque for top-end rush. And he'd still be buzzing at 3,500 rpm on the freeway. He decided to switch back to the 2.73:1 gears and enjoy the car the way it was-it would blow off  99% of the stoplight challengers he'd encounter anyway-12.80s is pretty damn quick-and the hell with the other 1%.  Another thing I may have talked about before was the buff magazines raving about the Edelbrock "Air Gap" Performer and Performer RPM manifolds when they came out. By raising the plenum and allowing air to flow under it, they gained 15-20 hp over the standard design. This worked great in sunny California. However-many readers in the midwest and Rocky mountain states who ran out and bought these manifolds after reading the article-because hey-you "gotta have" that extra 15-20 hp-were furious. Their cars absolutely would not start and run in cold weather. Many had problems with carburator icing, and many said they had to let the car idle for 20 minutes before driving it or it would cough, spit, stumble and die. That 15 hp didn't look so good then!!  The point being think carefully and make sure the "Pros" of your proposed addition outweigh the "Cons". Mastermind