Which number would you use for a Wallace calculator guess at Hp, Weight, and ET?

Sheet is for a 500 inch Brodix headed RB. Hp is 710, Corrected is 790.

Is that enough steam to push a 3000# A body to mid/low 9s?

Thanks!

Depending on setup, i assume 710 honest, at your DA during run, will get you 9.50s? Mineshaft air, obviously better. If your dyno numbers were with better headers, that may affect ootential ET. What is your motor, trans, etc combo?

Car is a 68 Dart. Looks like it has a good set of big tube headers in it. 727 stall unknown, brake, supposedly 4.88 Dana, ladder bar/coil over.

No idea on cam specs.

Just looking for a good guess.

We run in Michigan, Ohio, Illinois, Indiana, and Kentucky. In 11 years running my car I've never seen the air good enought to have a zero correction factor. Even in the spring and fall the best is about 3-4% loss. In the summer weve seen as bad as 11%. In our case thats 30-100 hp.
Doug

I don't care about corrected HP on engine dyno, it is just a correction formula number for what that motor would supposedly put out at 60 degrees F at zero humidity with 29.92 inches of barometric pressure at mean sea level. mid way between high and low tide
I did pay attention to them when doing flight planning in the summer flying in the Mojave Desert in the summer
Automotive and Aviation ISA (instrument standard atmosphere), vary by one degree F, Aviation is done at 59 F, automotive is done using 60F Not enough to worry over

Depends on the weather conditions that you race in. Here in the northwest we race near standard conditions a fair amount of the time so corrected power is okay to use. If you're racing in heat or at altitude you should stick with actual power since that is what you'll be making most of the time.

Do you know when and where the dyno testing was done? If it was done in the same area as where you'll be racing and if it was done during race season then use the actual number. If the dyno was someplace that you'll never race in then the actual numbers might not represent what you'll see at the track.

Right now our dyno is correcting power down not up. This time of the year the dyno correction factor is usually 98% or 99% so the actual power is greater than the corrected power. The air density meter in the dyno room was reading 107% yesterday when we were testing. Baro was at 30 and air temp was about 50 degrees. Only problem with those conditions is that the track would be so cold that nothing would ever hook up. But the engine would be making really nice power!

I'd use actual, not corrected. Not just for all of the many good reasons above, but it seems like Wallace calculations are given with the assumption that the chassis/traction/gearing is totally optimized. I've always used the conservative number, so there's a high level of confidence you'll run close to that projection. If the car is totally sorted out sharp, and you have awesome DA, then it'll be a nice surprise when it runs faster than the projected number.

My experience has been that for non-altitude adjusted tracks, it’s not at all uncommon to have the performance calculators show 5-15% lower power than stp hp from the dyno.
You have the combination of the parasitic losses that are incurred by running the transmission, converter, etc, along with how much the weather at the time differs from a “standard” day.
For altitude adjusted tracks, the difference will obviously be even greater.

In theory, the performance calculator is showing the in car/at the track power for that moment in time.
Keep in mind, the poorer the car set up is, the greater the difference you’ll see between the stp dyno hp and the performance calculator.

I have a few customers who run at fast tracks in good air where the stp dyno hp and the performance calculators are very very close.



Using the Moroso calculator, 10% off 790, at 3000lbs is about a 9.25

I'd think mid 9's wouldn't be a problem unless something in the car is way out in left field. My small block made 703 on the engine dyno and 545 at the wheels on a chassis dyno. It's in a street/strip 69 Dart, 727,4.10 gears with 28" tall radials, almost 3300# race ready. It went 10.008 @ 134.74 in poor air, the 1/8 mile et and 60' was off by over .1 and the mph was down over 1 mph. It's been 6.25 @ 110 in good air.

Thanks everyone! All I was doing is trying to give my buddy a ballpark on what his Dart should run. When he bought it there was a logbook from when the car had a 440 in it, but not the 500. I used the 710 horse and got 9.4X at 3000.