Trying to convert RWHP figures into concrete acceleration data from a dragstrip is pointless. Improving RWHP figures of a given combo is very useful as a tuning tool, but comparing it to another car is meaningless. Telling someone to swap their "inefficient" high stall equipped auto trans for a manual will get them a significant increase in rear-wheel performance but will more than likely cost them a few tenths at the track.
Take, for example, Doug Kelley's '69 Road Runner in the same issue ("Midwestern 'Tweeners"). Swap out his 4,500-stall TCI trans for a four-speed and he has a 400-plus rear-wheel-horsepower car instead of the 364 quoted in the article. He also would probably end up with a 12-second car that mph's well instead of the mid-11-second machine it is now. Hell, turbo rice rockets routinely dyno 350-plus RWHP in much lighter bodies with lighter driveline components but can't match Kelley's dragstrip performance.
I've heard the Turbo 350 versus Turbo 400 debate as to the increased horsepower consumption of the larger trans, but in the real world, ask anyone who has upgraded after blowing their TH350 and the TH400 runs just as quick. Even though it is heavier and theoretically more "inefficient," on a higher-horsepower car the loss is so small as to be insignificant and well worth the reliability of the TH400.
All in all, it was a good, informative article and certainly relevant today with all the chassis dyno shops and the popularity of dyno contests. It's just that rear-wheel dyno tuning is just that, a tuning device and not a great predictor of real point-a-to-point-b performance.
Tom Scala
Warren, OH
We agree with you that RWHP numbers are all about bragging rights, and it's the e.t. that tells the tale. However, we have to disagree about putting a manual trans in almost anything and assuming it will run slower. Take a look at the records in Stock Eliminator and it's clear that manual-transmission cars are always quicker. It may be true that installing a manual trans in a car will result in slower elapsed times, but only because the chassis tuner or driver didn't do his job. This is an important point. If the RWHP numbers are better throughout the entire power band, the car will be quicker, assuming the chassis is up to the task and the driver knows how to drive.
All In The Family
Above is a picture of my car along with my older and younger brothers' cars. My older brother owns the '69 Mach I with a 390 (we ditched the small-block) that's 0.030-over with a Crane cam; Edelbrock heads, intake and 750 carb; and a TCI trans and converter.
My car is the '30 Ford Model A coupe, with a 383ci small-block, forged pistons, Lunati cam, World heads, 2.05-inch intake valves, an Edelbrock tunnel-ram and carbs, MSD ignition, ATI manual valvebody trans, Trans Specialties converter, 3.89 gears, and a Detroit locker.
My younger brother owns the '70 SS Camaro. This car has come a long way in the last year with a 350ci small-block, a TH350 trans, and an Edelbrock intake and carb.
All the motors and drivetrains were assembled in my garage. I have had mine on the road for four years and this is my third motor, and I am happiest with this one.
Tony Sexton
Forest Hill, Maryland
Bolt-Ons Revisited
About the Sept. '03 cover-not to be rude or anything, but please, next time could ya put the girl behind the car? You just don't see a Chevelle like that every day.
J.M. Metcalf
Broken Arrow, OK
I enjoyed the hot chick posing on the Chevelle in the center this month, but please leave future hot chicks off the cover. I left my mag in the bathroom too long and my mom ripped it to shreds.
Melissa
Atlanta, GA
After picking up and looking at the cover of Sept. '03 Car Craft, my hands caught on fire and my heart was racing. The only way you could have had a better cover was replacing that car with a Rambler/AMC.