A hot rod channel for hot rod enthusiasts. I cover all kinds of awesome topics for muscle cars, race cars, motorcycles, drag racing, and so on. I deal with hot rod and racing history, engine theory, engine technical education, Harley-Davidson education, and much much more. After building engines for over 25 years and running a full time Harley speed shop for over 15 years I have accumulated a ton of knowledge I'd like to share. Want to make your car faster? I got the content you need. Want to rip down the road on your Harley? I got dyno proven proof of what works and what doesn't. Do you just like talking about and learning about cars in general? This is your one stop shop. Welcome to Rage Racing!
yea this formula is very close to real value for bike times fix very well speed turn out lil to high for me cb 500 it show 13,4 sec /102 mph me real world messurement 13,4 /97 mph in both dorection on flat tarmac no wind so very close for sv it show 12,3 / 111 mph vs real world data 12,3 /107 mph again time perfect vs speed lil exagerrsted but its for bike where cofsctor must be on 2,22 level +/- but it would depend on drag to weight to power level to gearing and peak width unless somebody know precise avg power in regard to oesk width and doffrences between gear lenght but in some cases from peak measured on dyno 100 hp can be avg use 70 hp cos peak be very thin feg and diffrences very big in somebascially all 100 hp can be use for accelerstion avg through whole distsnce at whell 👌🏻 so yea in some cases such cslculator can be waaay offf and in some very precise close to real test data 👌🏻🍿
mostly correct though not everything 👌🏻🍿 feg your car egzample with reduction x1,5 if it would have flat wide enough peak power and in stock form enough „everyhing” for go on limit of grip at launch ypur x1,5 times shorter final gear ratio will make it only slower as ypu will nedd to ups 1 times more before cors 1/4 mile finish line so such use less avg power so such „ggreat ewualizier „as you call gear ratios dont give you better acceleration at lower power no matter how you setup gearing cos what ypu miss here is SPEEED factor cos in racing we consider SET SPEED range accelerstion and not set gear cos nobody cares of somebdoy os at 100 km/h at 1 or 6 gear right ? what wr care is who win race thats makes diffrences 😉👌🏻🍿 …..atleast in next video ypu go directly into goal = topend power beat lowend torq at drag strip at perfect gearing each and the reason is so simple as this equation 👉🏻 power:speed= force👌🏻👉🏻 dosent matter what ypu do with gearing and how much more crank engine tprq ypurengine will have as long as ypu will use less avg power for accelerwtion at set distance of race YPU LOST 👍🏻🍿
Thanks for the comment and that is actually an excellent question I've been waiting for. For one reason the chassis dyno always measures horsepower. It takes a transfer of energy to accelerate a heavy mass up to speed. That energy is horsepower and the heavy mass is the dyno drum. The dyno does not measure torque directly. The Chassis Dyno calculates Torque at the engine. The dyno computer keeps track of how quickly the drum is accelerating and calculates how much horsepower is being delivered to make that acceleration. The dyno computer also reads engine RPM while accelerating the drum. The mathematical formula for finding Horsepower is (Torque X RPM) / 5252. Just the same the mathematical formula to find Torque is (Horsepower x 5252) / RPM. The dyno computer knowing the horsepower being put into accelerating the drum and reading the engine RPM at the same time does the calculation and shows you your torque output at the engine. Not at the wheel. If you run a car or bike or anything on a dyno whether you run in 1st gear, 2nd gear, 3rd gear or any possible gear you will always get the same result for horsepower and torque (minus things like frictional drag and differences in accelerating your own drive line). Try it. But you know 1st gear accelerates faster than 5th right? So what is going on? The chassis Dyno directly measures Horsepower. Your engine always makes the same horsepower no matter what gear you are in. The chassis dyno reflects this. Torque = (Horsepower x 5252) / RPM . As you run on a chassis dyno in 1st gear you have tremendous amounts of torque going to the wheel and the dyno drum because of the torque multiplication of your 1st gear. Thats why its easy to spin the tire on the drum and you can really get that drum moving fast as your engine hits redline super quick. Now go up to 5th gear and make a run. Now your tires are going a lot faster. The drum is spinning a lot faster but it takes a much longer time to rev out the engine. You are putting much less torque at the rear wheel because of the lack of torque multiplication from being in 5th gear but since the drum's (and your tire's) rpm is much faster using the above formula the Torque calculated at the engine is still the same. I recommend watching my other video about Torque vs. Horsepower. As an interesting side note. A engine dynamometer directly reads torque and uses the same calculation above to figure horsepower. So its exactly the opposite than a chassis dyno. I hope this answered your question.
Check out my next video "Racing Physics Class #3: Gearing, The Great Equalizer!" to see how these two vastly different engines fare against each other face to face in identical motorcycles simulated in a drag racing analyzer. The only difference between the two simulated programs is the engine output specifications for each engine, the final drive gearing, and the shift point rpms. Everything else being exactly equal. Which do you think would win in a drag race? The big engine with 121 HP / 118 Tq or the small engine with 123 HP / 82 Tq?
Isn't that 790 ft/lbs of torque if and only if the tire was the same size as the sprocket? I'm pretty sure you have to calculate the moment arm (distance from the sprocket where the torque is applied by the engine to the tire where the torque is measured).
@f.f.s.d.o.a.7294 only if you are applying the force from the end. Like if the force is being applied at the tire. The force is being applied from the sprocket and being measure a distance away from thr sprocket and therefore would be less.
torque is not measured it is calculated 😉👌🏻 from force and arm lenght ,torque egzist only in axis of rotation when he calculated torque from gear reduction it directly calculated torque ypu dont need tocslculated anything else 👌🏻 what he dont take i to considerstion is drive train losess ,but thats diffrent story .
Physicist here. It's nice to hear someone get it right. There is so much nonsense written about torque. The funniest is car magazines that list "torque at the rear wheel" as the engine crankshaft torque times 80% (or whatever they assume for the driveline efficiency). That works for power but betrays their lack of any understanding of what torque actually is.
Thank you for the comment! What got me through my Highschool and college Physics classes was mentally applying everything I was learning to drag racing my car. Thats the red Camaro from the video. Growing up as a gear head and having a basic understanding of what was going on in automotive applications sure made those classes much more entertaining and easier to pick up.
You might wonder why I used Torque as the unit of measurement going through these examples rather than Horsepower. The reason is Horsepower remains the same going through the gears. Horsepower is Torque x RPM divided by 5252 so as the Torque is multiplied the RPM goes down by the same multiplier. Therefore the Horsepower remains the same. Horsepower is a unit of energy. The energy always remains the same. Torque is a unit of force. The force can be multiplied but the overall energy going through the system will be the same from its source (minus small frictional losses of course).
I have modified and tuned V-rods as well. I like V-rods. But by far not the fastest things I’ve built that was American made. Keep watching. I plan to resurrect this channel soon. Put some good content on it.
Ive got some knowledge on turbos. I don’t like them on v-twins. What I do like and have experience building is v-8 roots style supercharger engines. If I had to build a v-rod turbo engine I would convert it to methanol to take advantage of the compression of the v-rod engine and cooling properties of the fuel so no intercooler would be needed then I would run boost to around 25psi to 30psi. Power at that point would enough to shatter the clutch basket and probably any part of the transmission and probably the bottom end (but I could be wrong). My feeling is if the Destroyer can run in the 8’s with naturally aspirated then the turbo is not needed.
