How much Horse power do you need

SteveS

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I have a class 1 car that i have ran in SCORE and VORRA. it has a stock LS1 in it right now. The car has a built th 400 built by the right guys and a 9 in, king shocks all 4s . I have an LS motor with 780 hp to put in it . i have worked out all the problems from the car being 1 off. so the question is how much HP do you really use or need? car weighs about 3300 lb
 

Huntington Beach

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If the drivetrain holds up then 780 is more then most 1's thats TT territory when you get that much Hp
 

SteveS

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Im wondering how much of the power is usable ? are the races coming down to that one wash so the guy with the ponies wins or is it just a cool thing to say i have X hp ?
CAN THE MAJORITY OF YOU GUYS with that kind of hp say its worth it . Fuel, parts ....
 

Atombomb

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Every car is underpowered until it's in the winners circle...Just keep in mind all of the additional tuning that is going to be needed to get the car back "dialed" with 100% more power.
 

SteveS

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Im on the road headed to tenn to get rid of my offshore boat , so i do not have the dyno sheet. i can answer that in two days. my guess by memory would be a lie.
 

Samco Fab

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To have the similar power to weight ratio as most of the winners, you need about one horsepower for every 7 to 7.5 lbs.

Your 3300 lb. car would need 440 to 480 HP to have the same horsepower to weight ratio as most of the front runners racing for the overall.

There is more to winning than horsepower, but you need the power to weight ratio at higher speeds. You need good power when you are going 70, and you need to accelerate to 100 quickly.

Also keep in mind, ( your hero Steve) RG has about a 6 to 1 power to weight ratio and unobtanium trans parts coated in top secret NASA coatings and then cryoed. This would mean you need 550 hp to run with the big big boys!!
 
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SteveS

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Samco i found that out at Hawthorn, I also found out to change the Heims sooner
 

GHARACING

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our last motor dyno'ed on a ENGINE dyno, with a tad bit bigger carb than we usually run, VP C12 put down around 770ish, there all kinds of opinions on how much hp is lost through the transaxle ect... im guessing we put down a solid 550-570 to the wheels depending on timing. just a guess.

when you can use the HP its nice to have! silt, lake beds when the rear bucks and you come down sideways and you have the power to throttle out of it.
 
M

memin.pinguine

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Not at all! It's more about how much money you can turn into noise.
That was meant as joke anyway.......

Samco Fab: I dont understand why parts with "unobtanium" are so expensive. You can have that here in almost every government office for free..... :cool:
 

FlyHiFlyLo

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Im on the road headed to tenn to get rid of my offshore boat , so i do not have the dyno sheet. i can answer that in two days. my guess by memory would be a lie.

Peak tourqe is where you want to aim your stall and ratio at. I seen your class 1. Is it an IRS 9inch? Or have you changed your car?
 
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FlyHiFlyLo

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One good thing about a lot of power is you can make beefier parts work better. For instance, with 450 HP you have to bump your ring and pinon up to a 5:50+. With how light your car is and 750+ hp you could probally go to a much more stout 4:56 r&p and be smoother on the gas.

One thing to watch for is trans temps when doing this. If you keep the trans cool (below 200f) you will have throttle on demand. Also, with more power you can change your 2nd gear ratio up closer to 1:1 and have an even lower stall, thus helps keep the trans cooler. Under normal opperating conditions every 10 degrees above 200f kills the life of the trans by 10%. It's a smart move to add an HP1 to the return side of the cooler line.

Basically the more power you have the more the engine can drive the car and less demand on gearing to do it. You want to be as close to direct drive as you can. Feeding power to the ground is always better than shifting it to the ground. Funny thing is this also helps your breaking too cuz you can allow more RPM in the engine to slow the car down.

Power is good!
 
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How far behind Letner was that 200hp BC Subaru at the last Baja 500? More hp = more breakage.
 

VeryFast

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Pistol Pete's PFAFF engine has over 500 ft/lbs of torque at 2500 rpm's, peaks at 646 ft/lbs of torque at 4600 rpms and maintains 500 ft/lbs of torque after 7000 rpm's. HP and Torque are only relative to the individual drivers abilities. We offered to build more torque, but Pete felt these numbers were good enough to maintain reliability and win. It appears Pete was right, now if we could have only had a 3rd fuel pump at Primm.

Most top runners in Class 1 have about 550 ft/lbs of torque. Anything more seems to break CV's.
 

3G RACING

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I think a better question is how fast can you AFFORD to go?
 

rickf

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"HP sells cars, torque wins races."

With all the modern electronics I wonder why off-road people aren't running variable horsepower programs (ala WRC, for example).
In first gear, 700hp gets you nothing but more wheelspin.
With fuel injection and computerized engine control it would be very easy to provide, say, 400hp in first, 500hp in second, 600hp in third and 700hp in fourth; for example.
Less wheelspin, more control and less parts breakage.
 
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