Meanstreak

Come on now... 25 years of drag racing experience should know better... You've got it backwards. DA affects stock / mildly modified NA cars more so than highly modified or boosted engines. Check out the DragTimes correction site and you'll see 3 different corrections listed based on your modification level. Stock is impacted the most.

Also you should make sure you are correcting each run to sea level for apples to apples comparison. The DA Correction algorithm is not linear. Adjusting one run down by 500 feet and the other up isn't accurate.

I agree the local track conditions will vary some from the NWS Reported data but it's mostly in temperature. Barometric pressure has the most significant impact and both Bradenton and Bartow show the exact same barometric pressure data for the baseline run so if I were a betting man I'd bet my next paycheck that it was the same at the track. The track DA may vary by a hundred feet vs the reporting station but it's a moot point for this discussion.

So based on the weather records during your runs the DA difference is quite a bit larger than you are indicating and equates to about 2.5 tenths. Sorry man but the facts are what they are. If you had run your car with the stock intake on 11/20 it would have run essentially the same time as you did wth the K&N. actually MPH is a much better indicator of HP so look at the bright side at least it didn't slow down like everyone told you it would!

ISFSCOTT

Put in any negative altitude number ( use -250) and tell me what the boosted and heavily modified et numbers do and the mph. Anything on the plus side between 0-1000 feet above is literally hundredths of a second difference, the same difference you would see with a few more gallons of fuel in your car, it is nominal, but yes slightly higher, I got ahead of myself. I have had my Mustang there on a -400 day once and it picked up 3 tenths and like 5 mph from 9.60 @144 to 9.31 @ 148.9 mph, it was nuts.

I made the adjustments using the weather from the designated times on the before and after intake runs to get apple to apple comparison, it is the same way when you bracket race. It varies more than 100 feet at the track than at the local stations because of the large lake across the street and the water droplets added to the air as well as the humidity from what I have been told. I literally have made at least 500 runs down that track on the low end and I think have seen most variables there. If you are ever there in the spring or summer and the flags stop moving, pack your stuff and leave, it will be raining within an hour. lol

My numbers are not quite a bit different and I am done debating this, I used a handheld device, used the numbers, plugged them in at home, and posted my slips. I do not get the desire to prove me wrong again and again when I have provided more data than any other thread I have found on this site, more than any of the shops that post on here even do, no knock on them. My MPH was up 2.5 mph and et's down .26. That is not all because of a DA that was 500-550 lower that day, plug in a 525 and use my et / mph then double the DA to 1050 using the same run for laughs, the difference is .09, not even a tenth on 525 more. The big drops to ET and raise in MPH comes when the track is at a negative DA and when forced induction or high hp cars really start to make free power.

At least you can admit I did not slow down because of the 27 knock sensors on the car. lol I am going to try harder to get them to knock next time though. What will everyone say if I go back to the track on a day when the DA is higher than my original stock runs and I still go a little faster ? Then what will the reasons be ?

lobuxracer

iTrader: (2)

You will still be a unicorn. That's the whole problem in a nutshell.

ISFSCOTT

Lol exactly. And I thought I was the only one that used that phrase. I think it boils down to most never take their car to the track, let alone a drag strip, so they have no basis for their argument other than just wanting to argue. A few in this thread obviously have raced before and made valid points both ways. Maybe I need a custom plate that says UNICORN.

autoz4me

You know what they say assumption is the mother of all bleep bleep bleep.

For me taking the car to a proper race track tells you more about the car than it ever will going down the strip.

It also improves you as a driver the more and more you do it the better you get in all aspects of performance not just putting your foot down and slotting gears.

Thats my thing with the strip it's straight lining its all it is.Granted setup reaction time and such count but I just feel you get a better reward as a driver at a track with corners.

mahcah

iTrader: (3)

I agree 100% ^^^

Helo58

Of all the people on this thread who have questioned anything you have supposed, I am one who wants to believe in what you put forth. I have an nice, freshly cleaned, well-maintained K&N Typhoon intake and new airflow sensor sitting in my garage floor just waiting to be used if it made an overwhelming improvement. Based on the abundance of anecdotal evidence provided on the forum and my brief experience with Honda intakes, it made perfect sense to me that it was possible for an intake to make no more power or actually lose hp or torque when installed. Lexus designed a two stage intake for a reason. I don't know that reason and can only assume why. I assumed it was because it improved low-end torque. Trusting that Lexus conducted their testing thoroughly, I felt this was a reasonable assumption. I mean if it isn't true, then who cares about throttle body size, intake runner length, velocity stacks, or manifold design... just get the air/fuel right and you are set right? Nope, not even close.

On my particular car, the K&N appeared to lead to higher trap speeds, but slower ETs. This supported my assumption above. I too did some formal and informal testing quickly leading to some experimenter bias where my testing confirmed my hunches.... and then it didn't. The number of variables that I came up with that could have changed from run to run included things such as: density altitude, actual fuel octane, tire temp, tire tread depth, track prep, track temperature, KCLV values, transmission control unit values for TC lockup and shift speed, wind speed and direction, intake air temperatures, 0.1 - 0.3 second variances in times during back to back runs with the same everything, etc. That is just the data that I could have collected in a best case scenario. I haven't even gotten to the actual analysis of the data. Do I compare the best run to the best run, the mean (average) of 15 runs, the median (middle) of 15 runs, or should I use 5 runs or 25 runs? The possibilities are many.

Yes, it appears that you have compiled an enormous amount of data to the best of your ability but you have also omitted a lot of data. The sheer amount of data collected isn't what makes an experiment or test accurate, it is the accurate collection and inclusion of ALL RELEVANT data and the proper analysis of that data. The more I looked into the matter and began to research, I realized that there were a multitude of conditions and sensor values that affect the cars performance to the degree that I could not account for accurately. Of the data you collected, your method of collection is less than confidence inspiring and good enough for a "cool, maybe it works" conclusion, nothing more. Out of temperature, barometric pressure, and humidity, humidity has the least effect on density altitude. Droplets in the air from the lake are no more likely to have an effect on you DA than water droplets in the air from the onshore winds from the Gulf. There would likely be little difference in dew-point measurements at either location. Also, DA readings in your case appear to be taken from at least 2 different places and possibly 3. Gauges in some dudes trailer, the handheld weather All-In-One device, and possible readings taken by the track itself (not sure if this is what was meant) are mentioned. Taking measurements from more than one source isn't a big help considering the possible variations between devices and calibration errors (compounded if occurring together) that could occur. Now factor in all of the other variables collected in a similarly haphazard way and you can easily arrive at a 0.2s-0.3s difference in ET.

Given that, to say that your "research" settles everything is a stretch. As the unicorn, you believe that your experience and outcome supersedes all other research on the topic and the experiences of a host of others to the contrary and solves the topic conclusively in favor of the K&N. That is bold and probably not likely. If you were Yukihiko Yaguchi, you might be able to make a statement that bold, but you are not. You are barely aware of the complexity of the ISF drivetrain and related sensors. I hope that you do understand that I, and most others, did not have the intent of proving you wrong. We are simply trying to get you to understand that the answer to this question is bigger than a couple of trips to the track and some incomplete data collection and analysis. The real answer to this question, unfortunately, cannot be arrived at conclusively without a much much greater effort. In the absence of that effort, we rely on the collective experiences of the CL ISF community. This is really what I think most people just wanted you to understand.

DjMarkOne

**** it. I say you hop on the dyno once a month just to see if your numbers change.

Davew77

If it's so easy, then let's see you go pull a 1.9xx 60' time at the strip.

The funny part is... almost all street races are basically a drag race. Maybe that's why nobody can ever beat me without a significantly faster car? Because they spend all of their time at the "real" track?

Drag racing is soooo easy... Just mash the pedal and go... Here's a nice long read just for properly launching a car:
http://www.baselinesuspensions.com/i...A_Drag_Car.htm


You should really know what you are talking about before you make blanket statements.

autoz4me

See that's the difference a lot could careless about a 60 ft time who cares lol.

I d much prefer to be to go to a 3 to 5 km track and put a lap together that entails using all the cars performance than worry about what it does in straight line.

Really who cares what it does in straight line you pretty much know what the car does in that regard to me what your talking about tells nothing about corners braking and actually how to improve your driving in general.

Thats the problem with what your talking about it's only 1 aspect.You go to a track with corners your measuring total car and driver performance.

If you want to beat on about straight lining all power too you but to me it's a complete waste of time and if I had to choose between a day at the strip or a day at a proper track the drag strip wouldn't rate a mention.

Vitveet

Both tracks require tons of driver and vehicle skills. One isn't anymore challenging than the other by any means. Could ha e a never ending argument about which track takes more skill...lol.
But if I had to put my input on it, the drag strip simulates street driving moreso than a road course. 0 to 110-120 is much more realistic street wise than taking curves at near triple digit speeds and hitting 130-140-150+ mph.
The IS F is very versatile and can do both tracks very well from what I can tell.

V.

lobuxracer

iTrader: (2)

Drag racing is boring. Wait 2 hours for an 11 second run. Wait another 2 hours for a second 11 second run. Boring. Road racing is brutal. Accelerate out of every turn as soon as possible. 30 minutes of non-stop drive it like you stole it.

I've done both. I've done quick quarter miles on bikes with the front wheel never touching the ground until I rolled off the throttle, or the bike never off the wheelie bars until I chopped the throttle, and I've done laps at Willow Springs, Sears Point, and Second Creek Raceway. Drag racing is boring. Sorry, but it's just my impression having both drag raced and road raced.

chris07is

iTrader: (10)

^lol...ur cold lance...but it's true...circuit track FTW!!!

Davew77

Apparently a lot of people care, hence the NHRA. By refusing to acknowledge drag racing you are only proving how closed minded you really are. Do you also own a BMW?

Have fun limiting your experience to only road courses. I am open to all forms of racing and THAT makes a person better than someone who only stays within their narrow vision.

DaveGS4

iTrader: (2)

Folks, if you can't keep the rude personal commentary out of your posts then do not reply to this thread.