Need a Good Website Calculator for ET to HP

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I would like to see what my engine is putting out in Engine HP, not wheel. Is there a good website calculator that factors vehicle weight, transmission type, rear gears, tire size and ETs at 30mph, 60mph, 60ft, 1/8th mile 1000ft and Quarter? If all it does is the Quarter I'll take it, better than nothing, but I got a Dragy and would like to find out what she's pumpin'.
 

Lefty71

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Google "dragstrip calculator".... there are several results, some of which we used to find useful.... maybe something there that will work for you??
 

replicaracer43

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ET is not how you calculate HP, its trap speed and vehicle weight.
 

318willrun

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Man, all I see anyone getting is a "general" at best ball park number. And that's using MPH from the time slip and weight at the start line. But sooooooo many variables still yet... HP = *** give or take 65 LOL
 

33IMP

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WALLACE RACING CALCULATORS.
He has about a hundred different kinds, for basically everything.
If you really wanna see how well your doing, plug in your numbers to his "ideal" calculator. Be warned......
 

33IMP

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Right, but without the tire size and the gears considered, it is not accurate the way I see it. A 500 hp motor will not produce the same ET with 3:23's as a 500 horse with 4:11's right?
ET will be different, mph, not so much. There would be more difference in an eighth mile slip than would be in a quarter.
The more optimized your car is for drag racing, the more accurate the analytics of your timeslip will be.
And yes, a 700hp car with a stick and street tires will lose to a 500 hp car with a great converter, suspension, and slicks, every time.... or, almost every time....
(and a calculator would NOT tell the guy with 700 hp that he's GOT 700 hp.lol)
 
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Thanks,

I don't have the 1/4 ET or MPH, I may get it this weekend seeings how nothing is calculable from the ETs or 1/8 ET and MPH. The Calculators are telling me I have 167hp pulling 2.07 seconds at the 60 foot mark?? It is a modified nicely 408 engine.

If I put my ETs up here for the 0-30, 0-60, 60ft, 1/8th ET and MPH and the 1000ft ET, can you give me a ball park what my "REAL" hp is?
 

RustyRatRod

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Post #7. Wallace has every calculator you could ever imagine.
 

33IMP

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Thanks,

I don't have the 1/4 ET or MPH, I may get it this weekend seeings how nothing is calculable from the ETs or 1/8 ET and MPH. The Calculators are telling me I have 167hp pulling 2.07 seconds at the 60 foot mark?? It is a modified nicely 408 engine.

If I put my ETs up here for the 0-30, 0-60, 60ft, 1/8th ET and MPH and the 1000ft ET, can you give me a ball park what my "REAL" hp is?
Yes, more or less, IF you can give us the car weight with you in it. Or at least describe the car as accurately as you can, and tell us your weight. (A hundred twenty pound driver will be quicker than a 380 lb. one.)
I've got two 500 fwhp cars, one is low eleven, one is high nines. The difference is weight.
ET is almost worthless for hp calculations if the launch is not optimized. Give us the weight and mph.
 
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For the quarter, I will have to see what it does this weekend. A 70 Duster 2900lbs, pretty much stock body, interior, about 3400 with the tools in the trunk, a pilot and co-pilot, a 360 block instead of the /6, the 727 instead of the 904, and the 8-3/4 instead of the 7" I think that came with the slant six which they calculated the 2900 with?? I could run by a cement plant some day and get an accurate weight if I'm lucky and the guy likes old cars. My 1/8th speed was 81.40mph. I will have to see what she does in the quarter. I am playing with mods, trying to see what helps the most. Tires are 275 50-15's, about 24-1/4", 3:23gears. It is a street car really.

RPM heads, 10:1 compression, Air Gap, 3-step headers, Holley 750 I have to get the cam specs if you need them, but its rather big, not full race though.

I appreciate if you could give me a ball park off the 1/8th. (81.40mph)
 

33IMP

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Example.
Guy with a nicely built 408, stock converter, street tires, and 3.23 gears goes to the drags, spins the tires ferociously, bogs when it hooks, and goes 14.50, at 95.
He buys a set of slicks, puts in a quality 3500 stahl converter, doesn't touch the motor!, and goes 13.50 at 105. Did the horsepower change, or did he just make the combo better?
The Calculators have to assume certain things for accuracy. If a guy is running a stick, spinning tires, bogging, missing gears, running out of fuel in high gear, NO calculator can give an accurate number.
 
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Gotcha. Sorry, forgot to mention I get almost 0 slip at the wheels, hot drag radials, 2500 stall, I know it is slight, built high performance trans, manual shift valve body, no missed gears, very limited tire slip, 8-3/4 built to race. 3" Exhaust out the back minimal mufflers. And 0 bog, hooks straight up.
 

33IMP

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You aren't gonna like it, but
Wallace says your 3500lb (a guess with a passenger weight added in) 81.4 mph is 293hp.
81.4 eighth should result in high 8.30s et, 1.84 60ft, 5.30s 330, and a 13.20, 100mph 1/4 mile.
 

crackedback

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ET is not how you calculate HP, its trap speed and vehicle weight.

Hits nail on the head...

ET is chassis/converter effectiveness
MPH is HP (with converter efficiency/slip)

Ever seen this? 450hp 3200# car run a 13.00 at 115 with a 2.25 60' time?

That's a 11.50 time slip MPH tied up in a 16.00 chassis. ET isn't reflecting what the engine is putting out.
 
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Hits nail on the head...

ET is chassis/converter effectiveness
MPH is HP (with converter efficiency/slip)

Ever seen this? 450hp 3200# car run a 13.00 at 115 with a 2.25 60' time?

That's a 11.50 time slip MPH tied up in a 16.00 chassis. ET isn't reflecting what the engine is putting out.

Found a dyno that I can launch on and run the quarter. That will give me all the engine data I need. Thanks.
 
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