Driving to the track will be no problem, it's just over 1 mile away. I drove it there and home with the slicks. Now with rpm calculators they are a lot better except allowing for converter slippage and I get this:
Now with 3.42 28" tire 70mph I'm at 2873rpm
switch to 4.11 gears and I'm up to 3452rpm
get the 4L80E I've been planning on and I'm lower than now at 2589rpm. Right?
Tony
1955 Bel Air Sport Coupe
My old 70 SS Chevelle with a 76 peanut port truck motor with a .500 lift marine cam used to do 1.98 60ft and 14.0 1/4s with 3.31 gears and 255/60/15 Goodyear radials. I forgot stock fuel pump and Holley 650 spread bore. 8.50 in the 1/8 is pretty good for a turtles 60 ft. If I recall Tony is opposed to buying a real torque converter which would fix the 60 ft issue.
Last edited by markm; 03-18-2018 at 04:45 PM.
Not at all. Just that they are calculating AVERAGE, not peak, power at the wheels. Any extension to flywheel hp has to assume some kind of loss through the drivetrain. And remember it's average over the entire run.OK, so are you saying the HP calculators that use weight, distance and time are bull?
The 4.11 gears you are considering will raise the engine rpm over the 1/8 mile. This will in turn mean more average horsepower because of the higher rpm.
I would not get too concerned with these numbers until you take it to a real track with real timing equipment and verify that the numbers you're now getting are even in the ballpark, because they may not be. markm's comment about a peanut port BBC going 1.98 in 60' with similar gears to yours is spot on. Your setup is either a dog or your timing numbers are suspect.
56 Nomad, Ramjet 502, Viper 6-speed T56, C4 Corvette front and rear suspension
Other vehicles:
56 Chevy 2-door BelAir sedan
56 Chevy 210 4-door sedan
57 Chevy 210 4-door sedan
1962 327/340HP Corvette
1961 Willys CJ3B Jeep
2001 Porsche Boxster S
2003 Chevy Silverado 2500 HD Duramax
2019 GMC Sierra Denali Duramax
It's just physics and math.
If you put 3000 pounds of force on an object and push it 1000 feet, you've done 3,000,000 foot pounds of work. That's how much energy you used to push it that far, no matter how fast you do it. The time element is where horsepower comes from. If you do that amount of work in 10 seconds, you've done 300,000 ft-lb/second of work. If you divide that by 550 ft-lb/second = 1 HP you get 545.45 HP. So it takes that much horsepower to do that much work in 10 seconds. Less time takes more HP, or conversely more HP can do the same amount of work in less time.
Horsepower isn't measured directly. It's a calculation, even when using a dyno. What they're doing is measuring torque at various RPM intervals, and calculating HP at those same intervals. HP = torque x RPM. At 5252 RPM horsepower and torque are equal, i.e. 400 ft-lb of torque ALWAYS gives you 400 HP at 5252 RPM.
56 Nomad, Ramjet 502, Viper 6-speed T56, C4 Corvette front and rear suspension
Other vehicles:
56 Chevy 2-door BelAir sedan
56 Chevy 210 4-door sedan
57 Chevy 210 4-door sedan
1962 327/340HP Corvette
1961 Willys CJ3B Jeep
2001 Porsche Boxster S
2003 Chevy Silverado 2500 HD Duramax
2019 GMC Sierra Denali Duramax