VORTECPRO

[QUOTE=coppercutlass;1207131]About 3500 lbs but i dont know how the calculators factor that stuff because ln one it says in 415 and one 369. The calculators say my 60 ft. Is good for mid 11's.[/QUOTE


I went through some time slips of various cars I've raced over the years and closest I could come to 11,80s is this.


60. 1.484
330. 4.571
660. 7.260
1320. 11.709

Typical times of a hard leaving high 11 sec "race" car.

coppercutlass

What was MPH on that slip ?. Im sure with skme 4.33 gears and a 4500 stall my 60 foot will be closer to that. My limitation is I still want a street car. I edited my last post so you might want to give that another look. Fwiw.

coppercutlass

VORTECPRO

MPH for the 11.70 was 110.9. The HP numbers I quote are observed crankshaft HP derived by MPH over 1320 feet which also happen to correlate with my own dyno testing. Example: My shop truck runs 101 MPH @ 4200 pounds, dyno HP was 331 HP observed, 101 MPH over 1320 @ 4200 pounds shows I believe 333 observed HP. Again 100% + efficiency with a street car very rarely done, especially on a budget-good combination.

coppercutlass

Im gonna sound dumb as hell but im cofused. The 369 HP figure you gave is what i get when I calculate HP from MPH and when I calculate HP from E/T I get 415 HP. How does that work ?. These calculators have always confused me. You mention observed cranck shaft HP does that mean crank HP after HP loss ?.

VORTECPRO

Ok, I will try and explain. You could have two cars that both run 111 MPH @ 3500 pounds, one runs 12.90, the other runs 11.85, so you can't figure from ET, HP is always derived from MPH. Observed means to me uncorrected data wether its dyno or track testing. So my trucks 331 observed, or in the room, uncorrected HP @ 6400 feet elevation, 23.56 baro was observed before the dyno corrected the 331 HP to 29.92 baro 60 degrees dry air HP which was 448 HP. Now if we took your engine and put it on my dyno in the conditions you raced in the observed uncorrected HP number would probably be around 370 HP, the corrected HP (29.92 60 degrees dry air) would be noticeably higher, probably around 425 just guessing, because you were not racing your car in 29.92 60 degrees dry air conditions, and then losses from turning accessories off the front of your engine.

coppercutlass

Now that makes sense. Thanks. The last time we went out was a nice high 50 degree day. I wanna say the track is at 700 ft. Elevation.

VORTECPRO

DA is one thing barometer is another, sea level barometer is 29.92 which is what the dyno corrects too, 700 feet is roughly a 29.20 baro, when the baro goes OVER 29.92 you are now super charging your NA engine for free. Example:

Current weather* for

Atco Dragway

in Atco, New Jersey

1. temperature = 47.25 deg f
2. relative humidity = 63 %
3. uncorrected barometer* = 29.97 inHg
4. corrected barometer* = 30.07 inHg
5. wind speed = 3.85 mph
6. wind direction* = NW (297°)
7. more info: current metric | historical | forecast | help

1. dew point = 35 deg f
2. saturation pressure = 0.327 inHg
3. vapor pressure = 0.206 inHg
4. grains = 30.1
5. air density (w/o water vapor) = 103%
6. air density (w water vapor) = 102%
7. density altitude = -678.46 ft

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Updated November 2, 2019, 7:27 pm

coppercutlass

I have lots to learn about weather and data logging . Thanks vortecpro now i have something to read up on over winter.