" Just step on it at 3500rpm in third gear, start timing and stop when you reach 6000rpm. "
Hey I like it! Tomorrow will do, as always with junk in the boot. After all it's a daily driver.
I'm putting the digital stop watch in my coat pocket now.

 

I will let maximus know about this

 

How about using a safe, legal way to compare performance?

http://www.ross-tech.net/andy/mini/d...artermile.html

 

Dude I'm telling you, this **** get's HELLA loud at 5000, 6000 stuff inside the car vibrates too much and it get's scary.

have a happy Turkey Day yo!

 

:smile:

 

Have you ever been to a dragstrip?

 

less wear and tear this way Andy...now put up your numbers!!

 

Yes, but not with the Mini. Again, why throw in all those variables involved in drag racing like launch technique, reaction time, shifting times...not to mention scheduling race time, racing fees, and again...wear and tear. Why are you suggesting we complicate things? One gear, one foot, one stop watch, limited speeds...what's not safe about that?

 

IMHO, there is a huge amount of error between people's reaction times between seeing the RPM on the tach to clicking on the stopwatch, etc. Also, the newer vehicles with lower gearing will have faster times, etc.

Anyway, here's an interesting fact. If you manage to get consistent and repeatable results for your car, then you install a new part and repeat the test, you can figure out how much you have improved the average horsepower of the car (as long as you keep all other things the same). For example, Randy's numbers showed:

3rd gear
Time from 3500 to 6000 RPM
Before: 7.5 seconds
After: 6.6 seconds

That's a HUGE difference. In fact, it's fairly easy to calculate the amount of kinetic energy that a moving object has (KE=0.5*m*V^2). Here's the cool part, the change in kinetic energy over the change in time IS POWER. So, if you accelerate a MINI from one speed to another in 7.5 seconds, then do the same thing in 6.6 seconds, you have increased the average horsepower from 3500-6000 rpm by the same proportion. Time is on the bottom of the equation, so:

1/7.5 = 0.133
1/6.6 = 0.152

That's a 14.3 % difference in average horsepower from 3500-6000 rpm.

 

Excellent to know and another reason to do this test!

 

3.8 secs average on 165-15 michelins smoking all the way with the nitrous on


And it was -2 this morning

 

I think a couple times in this thread the importance of noting elevation and temperature were mentioned. Also, even humidity should be I suppose, but to a lesser extent, so maybe not much of an influencing factor. Here's a really cool and fun tool that let's one see their impact:

http://wahiduddin.net/calc/calc_hp.htm

There was some minimal discussion here on that topic:

https://www.northamericanmotoring.co...=environmental

Having a shift light for such a test is nice, but not everyone will have one. I think this is a cool idea, and adds to our other data points provided by dynos, drag strip times, G-Tech, etc...

 

Set the cruise control at 3500 rpm. Press the gas pedal and the stopwatch button at the same time. Then all you really need to pay attention to is the end-rpm. Also, this is why people should do it 3 times and look for outliers.

They're saying 18 whp for the exhaust, so that's over 20 hp easily at the engine. Say 200/180 = 11%. That's pretty close! The additional airflow while driving (vs. the dyno) might make that ~3% difference.

 

ok I'll bite...oh wait...I don't have a stop watch...oh well...

 

Most cell phones have them built in under "organizer" or whatever. Check it out .

 

Now that's nice...not only do we have to watch out for people talking on the cell phones but those timing their acceleration with it too

I'll try to do the test sometime this week on my '02 S. The only drivetrain mod is a K&N panel filter that needs to be cleaned soon.

 

I would bet real money that the numbers done this way are LESS repeatable than using dynos. What it comes down to is elevation, temp, humidity, how full the tank is and on an on. As you add more correction factors, you quickly end up at something like SAE correction formulas.

The problem comes not from the dyno themselves, but that different types of dynos measure differently, and also have their own tendancies. Even with the same dyno, if you measure differenty (like RPM change per unit time) you will measure different numbers for exactly the same car and same conditions.

I did what you're suggesting (basically) with a TB and thought I'd seen an 8hp peak improvement. I was dead wrong. I took three TBs to my test spot and did runs (enough to determin measurement repeatability) and swapped the TBs on the side of the road to get about the same ambient. All the delta went away.

As an **** retentive experimental physicist, I have to say that good sound measurement theory and practice will lead you to good measurement numbers. This is just the point of the dyno, controlled measurement environment.

On Dynos, we tend to get cheap. Not enough pulls per car state is the first, crappy airflow simulation is the next area where we screw up, and lastly, we (the community) seem to think that dyno numbers can be compared to each other WITHOUT knowing the particulars of the dyno measurment, and this is most surely not the case...

I'm using a GTech, and it's repeatable as all get go. But I don't have an SAE correction mechanism (no barometer or humidity measuremets), so it's' hard to compare morning to afternoon, or one week to the next. But he GTech is about the cost of a few dyno runs, and you get unlimited ability to quantify (and the software allows you to get the time between RPMs or speeds as well).

For the original suggestion to method, I can't endorse it, as its unsafe as all heck unless you have a passenger, or are willing to have accuracy degraded due to poor measurement resolution.

Sorry....

Matt

 

I don't have a cell ...LOL...it's hard to explain...let's just say...when I wanna be reached I make my self available

but MLE does so I'll borrow hers

 

just let us have our fun

 

But your original post framed this as a way to get more accurate numbers. And for that, it will fall far short of the goal. For just fun, go for it.

For those that want a repeatable way to find our the advantage that mods add, other methods will have to be found.

Matt

 

• 37 Degrees
• I have no idea what the altitude is in Edison NJ on the entrance to the TP south.
• x-lites
• '05
• JCW intake
• right foot
• timex expedition
• as flat as the ground gets after the on-ramp, maybe slightly uphill
• no options on my car to weigh it down
• only had a chance to do it ONCE due to traffic

6.93

Seems too fast - will try again soon

mb

 

The 37 degrees and '05 gearing probably help a fair amount.

 

can't wait to try with my 02 MCS. We'll have at least 1000 miles to play with this week.

I hope I beat your 6.98.

 

dont get the msfit's confused lol...sid is MSFITOY

 

What about the SAE standard? That is why it exists.