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The thing about dyno numbers.......is it is JUST that, a number. You go into a shop, plunk down your hard earned money, tell them you WANT a 1200hp Predator motor, you can about bet they will produce a dyno sheet that says it makes that. But the race track doesn't lie. What does it weigh and how much mph does it run. THAT tells you how much power it makes.



I love reading the knowledge you guys bring to this forum as a non drag racer, from from my observations isn't the race track the biggest liar for actual power?

There are so many posts on different variables that effect track times that even a dyno seems more accurate. Tires, springs,shocks, aero, gearing, transmission, pinion angle, track condition, altitude etc etc all effect it. Even the driver has a ton to do with it, if I was in Al's car it would have the MPH of a slant 6 powered valiant wagon and he would need to replace the drivers seat due to random stains after I was done.

Plus it really discredits other forms of racing, Boatracers572 boat and diablo's pulling truck come to mind. I put my mud racing truck into the wallace calculator one day and my poor 440 was making something like 17 horsepower, and sometimes I don't even make it the full 200 feet.

Yes, getting the car down the track is important.........but is track time a liar about power?........absolutely NOT. ET the car runs is not representative of power, but MPH is. So the car can make a junk pass, but if it is making any power, it will be moving in the back half and those last few feet of the track where the mph clocks are. At a certain weight, HP should propel a car to a certain mph, that is simple math. If the engine is in the rpm range it should be, the converter slip is where it should be, it SHOULD run a certain mph range based on the power it supposedly makes.

I can run the numbers for our own drag radial car. If I input our best speed.....178 and our weight......2750, the calculators say we make around 2450hp. Based on our motor and the amount of nitrous we spray, I would say that number is very close. Now, if I input our best ET.........which is 4.16........and our 2750 weight, the calculator says just a little over 2000hp and I KNOW that is not right. ET is based on how you get the car down the track. Ours being a drag radial car we know we leave plenty on the table early as for ET, but we MAKE power, the mph and how fast we cover the back split tells me that

In general weather conditions, a 2450lb TS type car, with an engine that makes 1300hp......SHOULD run 7.30-7.40s in the 192mph range. If you look at the graph, the rpm is where it should be, the converter slip is where it should be and the car is running 185mph.......it is NOT making 1300hp. It is actually about 100 down from advertised. The math just is what it is.

I am NOT saying dyno numbers are useless. I dyno motors all the time. What I AM saying is that they are NOT the be all end all barometer of an engine, because those numbers can be EASILY manipulated, based on correction factors.

BUT, HP propels a properly set up car, at a certain weigh, to a certain MPH range. That's a true barometer. A prime example are some of the .90 class cars. They ALL run the same ET. But some run 150, some run 170. You put 20mph on another car, in the same class, at the same weight, you have WAY more power

NONE of this is a KNOCK on anybody, nor an attempt to diminish anything. You mention truck pulling. That is more about torque than raw power. So yes, you want to dyno the motor and see if the combination makes the power it should, where it should.

My observation was about the multitude of guys that tout "my motor makes X HP" because they have some dyno sheet that says it does, but the performance on the track does not come close to backing up that claim