# power to weight ratio

Discussion in 'The Garage' started by dirtwarrior17, Aug 5, 2005.

1. ### dirtwarrior17Banned

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How do you calculate your power to weight ratio?

Do you take the weight and divide by the hp or the tq... or both added together?

2. ### sled_dog1 ton status

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weight divided by hp, that would be lbs per hp.

hp divided by weight, that would be hp per lbs. Forget which is used...

3. ### ntsqd1/2 ton status

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Power/weight = HP/lbs.

4. ### BranndonC3/4 ton status

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is 13.75 to 1 good? for a truck that is

5. ### sled_dog1 ton status

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that would mean you would have 68,500 HP.... I screwed up, ntsqd is right, as usual...

6. ### Greg72"Might As Well..."Staff MemberSuper Moderator

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So I guess the answer is "YES"...

There's a lot more to performance than a power/weight ratio, but as a general measuring stick it can be somewhat relevant. Take a look at vehicles with in the 20lbs/HP range, then in the 15lbs/HP range....and on and on.

The "hot" cars might have a ratio in the low-teens.....crotch-rocket bikes are something like 3Lbs/Hp.

If you know your vehicles ratio you can get a REASONABLE idea of the performance by comparing it to other vehicles with similar ratios. The things that make direct comparisons tricky are: overall gear ratio, gear spacing in tranny, available traction, frontal area, etc.

I'd like a K5 in the 10Lbs/Hp range..... I think that would be a fun toy. A motor with around 500Hp would pretty much cover it.

7. ### pismorat1/2 ton status

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Mine is 11.2lbs/hp. Thats 475hp in my 5300 lb. I haven't gotten a chance to open her up yet...but I can't wait!!

8. ### DavidB1/2 ton status

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9. ### DavidB1/2 ton status

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I"m curious...I have a dodge ram with a cummins diesel...say i hopped it up to 500hp and 1000 ft/lbs...seems like hp/weight numbers would make it seem slow (weighs 7400 lbs)...but the tq makes it faster. like was said, there's a lot more than hp/weight, i guess.

10. ### dirtwarrior17Banned

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15.76... not bad but still a long way to go.

by the end of next year it will be more around 13.00 when i get some darts and a good cam.

11. ### CyberSniper1/2 ton statusPremium Member

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Anything that isn't 10lbs/hp or less isn't considered to be "performance". 20 is on the slow side. 15 is good.

20 is average for a pickup.

12. ### dirtwarrior17Banned

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Tell that to civic owners......

13. ### CyberSniper1/2 ton statusPremium Member

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They're usually happy if they can break the tires loose with the parking brake... or if they have a hint of torque steer.

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