Gary Ugarek

I love a good debate avbout engineering and controlled testing.

I am an Engineer.

Derf00

Hmm.. I've read most of the posts with much amusement. Not because one post is more correct than the other but because something is painfully missing from the consideration that has been brought up indirectly to one degree or another by both sides.

Opportunity cost.

If it costs you say $300 for a CAI to save 1-2 mpg per gallon. But then it takes the course of 2-4 years or more to make up for the cost. You haven't saved anything, you just broke even. You are started off $300 in the hole when you bought it.

So in essence you saved nothing.

Here's some better advice, use the cash to buy a share of tech stock and sit on it for a couple years. At least at the end you'll have something tangible that actually increased in value instead of broke even (unless you didn't research before you bought )

BTW, I hear turbonators help to atomize the fuel better thereby making the burn more efficient and allowing a more complete and more clean combustion. Thereby increase MPG by 2-4 mpg.... I sell them from my igloo in the middle of Times Square.

P.S. I have my space age fire proof suit on so nanny-nanny-boo-boo, I'm rubber you're glue whatever you say, bounces off of me and sticks to you!

Nuke

C'mon, brother. I hit that in post #6.

Derf00

Yeah you did elude to it, I guess I just further spelled it out.

jz78817

Me? Never. but you need a controlled environment in order to perform a proper test. It's why the EPA fuel economy test procedure is done in a lab, with strictly controlled environmental conditions, and a trained operator driving the car according to a clearly-defined procedure. That means the operator has to accelerate, run at a steady speed, and decelerate while following a defined profile; if the operator doesn't hold closely enough to the profile the test is invalidated and has to be restarted. By testing under controlled conditions in a lab, they're testing the car alone. If they did the test on the road, they'd be testing the car, the weather, the wind, the road surface and grade, etc.

No it isn't. the other variables in play are ambient air temperature, barometric pressure, humidity, wind speed and direction, tire pressure and temperature, and- most importantly- driving style. There's a concept in STEM fields called "design of experiments." If you want to evaluate the effect of a change (say, how a CAI affects fuel economy) you have to keep all of those other variables constant. Meaning, in lab conditions you test the car with the factory intake setup, and then (knowing you have the same air temperature, pressure, etc.) test with the CAI. If you don't control all of those other variables then you cannot be certain that the CAI is what gave you any putative mpg gain. You may think you're "driving the same way every time," but unless you're actually tracking throttle position vs. engine RPM vs. road speed, you really aren't.

no. see above. even tiny differences in driving style can have a huge effect on fuel economy. Ever watch your instantaneous fuel economy display? Ever notice how a tiny change e.g. 1 mm of throttle opening or 1 mph difference in speed can represent a 4+ mpg difference? When you want to test the effects of changing one variable, you MUST keep all other possible variables constant or else you don't know what actually influenced the change.

this doesn't make any sense.

now you're just trying to save face. An "engineer" thought process is what got your car designed and built. An "engineer" thought process is why your engine makes 435 hp from 302 cubic inches when only 20 years ago such an engine wouldn't even be able to idle. Recalls happen for a number of reasons, but attributing it to an "engineer" mindset is ignorant.

cruisin5268d

I'd like to see someone test their precious aftermarket intake with the stock tune...but then we would be comparing apples to apples, and we just can't have that in this thread.

Keep taking your placebo pills and drinking your Kool Aid.

Gary Ugarek

I ran my boss 302 intake on a stock tune for over a week. I didn't want to switch tunes until all of my other parts were installed.

I call BS on a lot of the "issues" these aftermarket claims of needing a tune. I am sure a tune will help handle things better, but in the long run if the parts are made correctly and fit as intended you can run without a tune.

In case anyone has forgotten our cars have a computer in them that is constantly learning. OBD II can adjust the timing and spark as its needed (within limits) and compensate for certain parameters running out of tolerance zones.

Every time you start your car the computer is learning. You're in traffic the computer knows to adjust for stop n go, on the highway the computer knows it can make adjustments so there is no constant need to keep changing parameters.

The only time the computer is playing catch up is on the track. If you go from ho-hum driving to buck *** wild track driving your first pass is going to the ECM learning what it is you're doing, most second passes are better because the computer now knows you're going ***** to the wall nuts on the accelerator.

PNYXPRESS

I did. If you read my posts I said I did that.

My GT was dyno'd 100% stock then with just a K&N CAI, then again with a BBK CAI/tune.

CAI/stock tune gained hp and mpg over 100% stock, CAI/tune gained hp loss mpg over both.

jz78817

why do you keep bringing up dyno numbers? dyno pulls are done at wide-open throttle and nobody here is disputing that a CAI can flow better in this situation and give you hp gains.

what we're talking about is better fuel economy. here's a simplified picture of what the intake system looks like when just puttering around the road. even at highway speeds you've got the throttle plate barely cracked open:



zone 2 (the slightly open throttle plate) is so restrictive in this situation that it has the single most dominant effect on total airflow through the engine. Why on earth would you expect making "zone 1" freer-flowing to make a damn bit of difference in this case?

outceltj

Engineers take a lot a slack. But without them we wouldn't have today's ponies producing. Granted there are guys that aren't engineers who can do some damn good work. I think engineers get a bad reputation at times bc when one graduates college they still have to be trained to a certain job. Take the oil field industry for example I use to supervise a frac crew with newly hired engineers. They had to spend six months on equipment before being moved into the data van to start learning there actual job. After about 8 months they are generally on there own working closely with the supervisor. I find it odd that they get hired on at said salary which is basically a bit more than the supervisors base salary. All the while the supervisor has to train the engineer. For the most part I think this is why people get jaded. This circumstance will never change as engineers will always be considered the best option for the future of a company.