TurboSize.XLS - an Excel spreadsheet I wrote to
compute engine performance for normally-aspirated and turbocharged engines.
I've put a ton of work/research into it and gotten a lot of good feedback
on it.
0-60.XLS - a spreadsheet that was given to me. This
one estimates 0-60mph times based on 1/4mile timeslips.
Fuel.XLS - some raw data that I incorporated into
my turbosize spreadsheet.
Walbros.XLS - more raw data, for the Walbro
in-tank fuel pumps.
Scans.ZIP - 3 log sessions from my OBD-2 scanner.
Go to http://www.obd-2.com to get the
software for manipulating these logs. The first session just records engine
speed, airflow, and throttle position for a WOT run. The next session adds
intake air temperature. The last session monitors all available parameters,
over a variety of driving conditions.
EngineVE.XLS - A compilation of data from
scan7.log showing Volumetric Efficiency. The VE figures were copied in
by hand after feeding the other numbers into TurboSize.XLS. I suppose
when I get some time I'll copy the formulas over...
 A screenshot showing plots of Engine Speed, Mass Air Flow, and Throttle Position. This data comes from scan7.log in the ZIP file above. |
 The previous data exported into Excel, where I computed Volumetric Efficiency from the given data. |
 A shot showing most of the available parameters on my car. |
| Run | Time | Conditions | Actual | Corrected | Correction Factor |
| ||||
| Temp ° F | Press in.Hg | hp | ft-lbs | hp | ft-lbs | |||||
| 1 | baseline | 4:08pm | 60.4 | 29.81-0.44 | 142.0 | 142.1 | 138.6 | 138.7 | 0.98 | |
| 2 | baseline | 4:10pm | 60.1 | 29.97-0.43 | 143.3 | 143.3 | 139.0 | 139.9 | 0.97 | |
| 3 | HotShot | 4:34pm | 59.9 | 29.92-0.44 | 147.5 | 148.6 | 143.2 | 144.3 | 0.97 |
|
| 4 | HotShot | 4:35pm | 60.0 | 29.81-0.44 | 142.9 | 143.2 | 139.5 | 139.7 | 0.98 | |
| 5 | spindown | 4:53pm | 60.2 | 30.02-0.43 | 144.2 | 146.1 | 139.5 | 141.3 | 0.97 | |
| 6 | spindown | 5:20pm | 59.3 | 29.92-0.44 | 143.9 | 145.4 | 139.6 | 141.1 | 0.97 | |
Here are three runs from August 10, showing only the AutoPhysics QuickChange air intake. I'm sorry I didn't get baselines with the stock intake to correspond with these runs. Since the temperatures are so different from the March runs, the results aren't really comparable, despite the Correction Factor. As before, altitude is 0 ft, and (even with my new wheels and tires, yay) the stock gearing 63RPM/MPH. Run #9 was with the hood shut - as you can see, it made very little difference.
| Run | Time | Conditions | Actual | Corrected | Correction Factor |
| ||||
| Temp ° F | Press in.Hg | hp | ft-lbs | hp | ft-lbs | |||||
| 7 | AutoPhysics | 2:25pm | 84.6 | 29.92-0.44 | 140.8 | 135.9 | 140.6 | 135.7 | 1.00 | |
| 8 | AutoPhysics | 2:29pm | 84.8 | 29.92-0.44 | 137.8 | 134.8 | 137.6 | 134.6 | 1.00 | |
| 9 | AutoPhysics | 2:34pm | 85.5 | 29.92-0.44 | 137.5 | 133.0 | 137.4 | 132.9 | 1.00 | |
On March 6 a bunch of us in the SCPOC went down to the Carlsbad Raceway to drag race.
This was
my first drag racing experience. Of 5 runs that day, my 3rd and 4th were the best.
This is the timeslip from the 3rd run.
Bottom line, 1/4 mile in 16.196 seconds @ 85.81mph. (Car #54, left column.)
Today I was looking over my dyno results again, and plugged in the numbers from my
March 24 baseline runs into CarTest 4.5. Using a clutch-slip launch at 2000RPM,
this is what the program predicted for an optimal run.
Bottom line, 1/4 mile in 16.2 seconds @ 86.8mph, with optimal shift points.
At the time, I was a little disappointed that I couldn't break into the 15s all day.
Now I look at it and realize I already did as well as could be expected. Better than
the computer, in fact. (I tried clutch-dump at first, but got way too much wheel hop.
I suppose with spongy race tires it would have been feasible, but not on stock
Gatorbacks!) So I guess a career as a drag racer isn't hopeless for me after all...
(No thanks.) By the way, photos from my 4th run are on
http://highlandsun.com/hyc/. Yeah, that's
me in my bone-stock GTS trouncing a 3rd-Gen RX-7 past the 1/8th mile point, despite
having a .1 second slower reaction time and no turbo. Yeehah! He still won in the end,
by .25 seconds (16.141 to my 16.394). Oh well, it really should have been "no contest"
from the get-go. I'm pretty happy to have done so well - heck, if I had run another
16.2, and reacted just 6/100ths of a second sooner.........!
Note - the CarTest results were obtained by entering the dyno numbers into the Car
Specific parameters, with all driveline loss percentages set to 0 (since they are
inherently part of the dynojet numbers, and don't need to be computed again...).
List of mods:
