Hey yall i was reading some past topics and read something about power to weight ratios. I was wondering how do you calculate you own ration on your own quad. Like my z for example. I would say it has maybe 40 h.p. I am running true blue race fuel which is like 112 or 115 octane, plus a quarte of methonal for every 10 gallons of gas. I know that will boost the power some. Oh and if a stock z weight 375 lbs dry, mine should weight around 365 dry. I have removed the heel gaurds, and made my own brackets to hold the fenders at the bottom using the old bracketry. I have cut the front fenders off, installed lighter aluminum rims, with light 2 ply tires, the pipe removes several pounds, and the grab bar is gone also. So i figure that is an 8 to 10 pound weight loss right. So with that what is a round about figure for my power to weight ratio? Any help is appreciated, thanks. Peace.

 

You have to figure everything when it comes to power to weight. You did not say how much you weigh but lets say it's 175.
175 + 365=540lbs total weight.
Total weight divided by HP= Power to weight.
540/40=13.5
Your power to weight is 13.5 to 1.

Lets do my V.

520+200= 720lbs
I don't know what a V puts out stock but lets say 50HP
720/ 50= 14.4
I have a 14.4 to 1 power to weight.

If you and I drag raced and all else was = I would be eating dirt.

 

well i weight 140. So what your saying the lower the first number the quicker your gonna be? If my math is right my ratio is now 12.625 to 1. Is that good. I am talking for the 300' strip, and i am gonna be running a wheelie bar. I am a pretty good ryder, so if everything is good what is a good estimate for me on the 300? Thanks.

 

That's what I'm saying.
For another example:
The drag car in my picts weighs in at around 2400lbs with me in it.
The motor puts out around 500HP.
2400/500= 4.8 to 1 power to weigh ratio.

The car I'm building is going to weigh in at around 2000lbs with me in it.
The engine I have is right at 600HP.
2000/600=3.3 power to weight.
Needless to say the car I'm building is going to be way quicker than the car I drive right now.

I can't say if that's good or not. If the guy your racing has a 150hp Shee, and weighs in at 400lbs total, no; that's not good.
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Even if you race a guy your size on a stock V it's going to be close..........real close.

There is tons of things to think about in a drag race. Over all weight, rotating weight, HP, traction, and many, many more. There is no way myself or anybody else is going to give you an accurate number. Ballpark, maybe.

All in all, the name of the game is you try to get the weight number as low as you can get it and the HP number the highest you can get it. If you can get those #'s better than the guy your racing, you going to win the drag race if all else is =.

 

another thing to remember in power to weight ratio, is that in a drag race there are other thing that matter also. Things like your engines powerband, how much HP it makes down low and up high. You could have a 100HP engine but if the transmission is geared too high, you'll take forever to get up to speed, especially if that 100 HP peak it at like 6000RPM. You're not spinning 6000RPM when you take off, so peak HP doesnt really fall into place at that point yet, it's TORQUE that matters there.

Not trying to pick on your thread at all, just throwing that into the mix, so we dont have all these "my power to weight ratio is batter thatn your's" threads popping up from people that dont understand or oversimplify the concept.