MaxSE2k

Ok - so Saturday morning I've got an appointment @ the dyno shop for my before y-pipe installation run, and I figured while I'm there I'd compare the PR CAI vs. the upper pipe alone (Frankencar). Here's my conclusions - remember, I've also got a cat-back:

PR CAI - Max HP = 212.1 Max Tq = 236 HP @ redline = approx 198
WAI Setup - Max HP = 218.7 Max Tq = 235 HP @ redline = approx 212

Peak = +6 HP benefit to the WAI
Largest Margin = +14 HP benefit to the WAI @ redline

Another piece of info - the shop was intrigued by the difference in performance between the two setups, so we went for a drive with their ODB II sensor(?) hooked up, and logged info on air temp - both setups were reporting the same air temp... confirming that there's enough air flow under the hood to keep cool air passing through the filter - and it's safe from the elements. Read on.

Ok - so now I'm convinced that the WAI is the way to go, but I couldn't completely uninstall the CAI snorkle tubing at the shop, so I reassembled everything for my drive home, running the CAI. Oh - BTW - it's also raining out... So I get home, grab some lunch, head out to Home Depot, and my car starts bogging - bad. It actually stalls - twice. I suspect that possibly my filter had fallen off because I may not have re-tightened it enough - but no. I get home, my filter is attached but soaked... freaking out, I disassemble the entire intake system, and traced water all the way up to the throttle body. Immediately I put a bottle of dry gas in, dried all the tubing, used another cone filter I had which was dry, and ran the car for an hour. This morning everything seems fine.

Should I have done anything differently?

If the information provided above isn't enough evidence to stay away from a CAI - whether PR or Injen... get your head checked.

jjames

*** Good info. IMHO, calling an intake a performance mod is a bit of a stretch.

Soon2BMaxed

OK, but theres one factor you're leaving out. What sits in front of your car when it is dynoed? A FAN blowing air into your engine while the hood is propped up. With the CAI the filter is sitting in the fender.....NOT in front of a fan. So you can't really call the two different dynos "fair". But anyways, I think everyone pretty much agrees with the fact that the design of the PR CAI makes the tubing too long thus greatly hurting top end power. And if you don't think that the fan makes that much difference in a dyno think again. When me, Dave B, and several others from our board when to dyno my friend brought his Spec-V Sentra along. We dynoed once with the
normal "Hybrid" or "WAI" set-up and on the second dyno we simply attached the intake at an angle on the TB so the filter was sticking somewhat in the air towards the fan and he gained 9fwhp and 11fwtq. That right there shows the difference between having a fan on the filter and having it blocked by a fender.

Trevor

p.s. I also use the PR "Hybrid" set-up

BlackMax2k1

iTrader: (1)

I think people who don't have any performance mods shouldn't reply.

SkylineGTR

The air intake temp was the same while moving. Kinda gets rid of advantage of PRCAI, except when the car isnt moving, or at low speeds, which would show why the PRCAI feels a little stronger down low, idle to 3000. If underhood temps are same while moving, say 20mph or higher, then the entire advantage goes to an underhood intake setup, bc the CAI isnt sucking in any cooler air.

Soon2BMaxed

I think low-end is the ONLY benefit of the PR CAI.

SkylineGTR

If the same holds true for the SpecV, while moving the intake temps between a CAI and WAI are same, then the gains seen from pointing the filter towards the fan, is closer to a real world gains.

Soon2BMaxed

I agree but...I'm not sure I see what you're getting at please explain....do you agree or disagree with me?


Trevor

MaxSE2k

okay - how about if I told you that I asked them not to have any fans blowing? There - that shoots down your theory there.

jjames

*** Performance mods like your shift ****?

Cutler

iTrader: (3)

Close the hood on your car while it Dynos with a WAI, let it suck in the hot air motor Remember Real world driving is a better indicator of the performance of an intake. I had a berk POP and then went to the Injen and I tell you that the Injen is a much better intake. In the 1/4 I do agree a hybrid will yield higher trap speeds, but in everyday driving I like the Injen better.

Jason

BlackMax2k1

iTrader: (1)

Your right, the only thing I have is a shift **** for performance.

jjames

*** What happened to your Injen CAI,RVM Racing UDP, and Courtesy FSTB?

Soon2BMaxed

ok but your hood was still popped up right? why don't you try it next time with your hood down? i agree with you and all but the point i was trying to make is there are other variables involved during dynos...

SkylineGTR

the intake air temperature was the same when the car was moving. No one runs a quarter mile while standing still. Under load, IN MOTION, both intake temps were the same, meaning the CAI was drawing in the same temp air as the underhood intake, while the car was being driven, the CAI took in same temp air, just had more piping to route it through. He eliminated all variables, by taking the intake temperature and finding that they were even. By leaving the hood open, and letting the WAI draw in outside air, which is cooler than engine bay air, he set the variables even for when the car IS in motion. If the car is in motion the intake temp is same. If u close the hood and let no air go into the engine bay on the dyno, then u created a variable by making the underhood intake draw in air that is at a different temperature than from the CAI.

SkylineGTR

Leaving the hood open while dynoing a WAI recreates a scenario if the car was actually moving. Leaving the CAI where it is, recreates a scenario of the car in motion.

Dynoing the WAI with the hood down, would create a variable thats non existent while the car is in motion.

Soon2BMaxed

that is the whole point! the WAI sucks in WARM air and the CAI sucks in COLD air...... get it now? they should be tested like that because it makes it more fair. BUT either way....WAI is still better. This is pointless, im not responding to this thread anymore LOLZ

SkylineGTR

THE AIR INTAKE TEMPS WERE THE SAME BETWEEN WAI AND CAI. While the car was moving BOTH intakes drew in air at the SAME TEMPERATURE. If you CLOSE the hood, then they NO LONGER draw in the SAME TEMPERATURE AIR on a dyno. Closing the hood would NOT create a fair dyno to the WAI, bc while the car is moving it DOESNT draw in warmer air than the CAI. If u dyno with the hood closed, the air that the WAI draws in is WARMER than the the air that the CAI draws in, but while the car is MOVING, they both draw in the air at the same temperature. Not trying to sound hostile, but this guy proved it ultimately. WAI IS better, and there werent any variables. Only way the hood being open would be a variable is if the WAI drew in WARMER air while the car was moving, but it DIDNT, all that talk about what people have been saying that the WAI would draw in warm air from under the hood has been incorrect, once the cars gets moving, both CAI and WAI draw in air at the same temperature.

jcphamer

an intake is an intake is an intake is an intake..... they are all the same......it is just what you like whether it is hot or cold, loud or quiet...

SkylineGTR

WAI will suck in warm air if the car isnt moving, but once its moving, WAI and CAI draw in air at the same temp. If u dyno with the hood closed, then the actual gains from a WAI will not be seen, bc ur making it draw in warm air that it wouldnt draw in when moving.

SkylineGTR

yea but with this little dyno comparison, and him finding that once the car gets moving, the CAI loses all its advantage, bc both CAI and WAI draw in the same temperature air. 6hp peak and 14hp at redline, thats pretty big, considering that means those are the differences once the car is moving. WAI for me

DTR Maxima

these dynos are getting us no where. theres always a fan, moving, air temp, not fair to variabled conditions argument. i want to see some track times. someone please do the test at the track opposed to the dyno

Cutler

iTrader: (3)

BlackMax2k1

iTrader: (1)

You make no sense. Just drive your stock car. I'm sure it's good for groceries.

SkylineGTR

there was no fan and he proved that while moving, air intake temp is equal. he proved that the CAI draw in the same temp air, with more piping, therefore the WAI is better. Also the best times posted by maximas all run WAI.

SR20DEN

iTrader: (7)

http://www.acsu.buffalo.edu/~attse/honduh.htm

Anachronism

Do you have the dyno charts? Did the CAI make more power at loer RPMs? Does anyone think the WAI had an unfair advantage since your ECU had already adjusted to it?

MaxSE2k

They close the hood for safety, it was propped like 1/2 inch to not crimp their wires. Again, no fans.

MaxSE2k

I do have overlayed prints. Up until peak hp they are both equal, but the CAI deliveres a bit smoother TQ curve at lower RPMs.

I had been running the car for a CAI so the ECU was adjusted for it.

Face it - all odds were against the WAI setup for all you doubters, and that's fine - but the numbers make my argument. AND - the water soaked filter says something too. Did anyone ever take that into account?

03BlkSETE

iTrader: (3)

Thanks for doing this test. I know their are many possible variables when running a dyno test but it sounds like you did a good job taking them into account. I was leaning toward an Injen intake but this is definitely making me think about the Frankencar. Good test.

Anachronism

The water soaked filter is definatly a bad sign, that is my biggest fear with a CAI setup. AFAIK no one on this board has had water problems with a CAI. The fact that the CAI filter gets dirty quicker and is a PITA to get to to clean are also factors.

What temp sensor was the ODB II reading and where was it located? What temps where you getting (compared to outside temps) and how did they change at speed? I did an intake temperature test to use as an argument against the CAI guys but was disappointed to find that while the temp varied overall, at idle and low speeds it tended to be around 30 deg above the outside temp . This translates to about a 6 HP difference using the SAE correction factor for HP (1% per 10 deg X 200 HP). However the 6 HP advantage of the short ram neatly cancels out the temp advantage and it only gets better at speed when air is rushing under the hood.

I currently have a hybrid setup and after my temperature test was considering changeing to a CAI. But now looking at your results I will probably stick with the hybrid and work on some sort of heat shield. Your temperature results seem to contradict mine , was the CAI pulling in air at or near the outside temp? I wonder if the hole in the fender for the CAI helps bring more cold air in for the hybrid setup.

Thanks for doing the test, it is nice that people are willing to share some hard numbers on this. If you are going to re-dyno anyway perhaps you can do both intakes again with the ECU adjusted for the hybrid to see if it has even more of an advantage.

jjames

*** Stock car? Like Winston cup? No, no, no. It's a Maxima. But you're right. It is great for groceries. Lots of trunk space, and one of those cargo net thingies to keep the bags from falling over. Works great. Of course you already know that, considering you have pretty much the same car.

deezo

iTrader: (3)

You know.................your right!

2002Maxxxima

I will not be getting a CAI for two reasons:

1. No significant gains over WAI.

2. Since all of the CAI have the potential to get wet one way or another. Not that I'd ever be in water deep enough to suck water in, however, if the filter is wet, and I live in Ohio, what happens when I get my filter wet, park somewhere, it get's really cold, and my intake filter is all frozen up? Looks like WAI is the way to go for me. IMO.

Thanks for the info MaxSE2k!

BlackMax2k1

iTrader: (1)

Thanks Deezo. jjames is the anti-mod.

BlackMax2k1

iTrader: (1)

Right

jjames

*** Oh now, c'mon. I am not anti-mod. Sheesh. Don't take it so seriously. There will always be a "I love my intake camp" vs "why would I spend $200 for 3 Hp camp".

Besides, I have mods. I have a radar detector and new tires. Aren't those mods?

I am seriously not anti-mod.

SteVTEC

MaxSE2k, great post and thanks for the write-up. This is the proof that we need to back up the theory.

DE-K's need all of the low-end help that they can get, and you have an automatic. I don't doubt that a hybrid or CAI would give you better daily-drive performance than a POP setup. But in the end, when you're flat out, top-end is what you need. That's what a CAI doesn't give you.

I'm going to be ordering my Frankencar hybrid soon

Cutler

iTrader: (3)

true, auto needs the help. I would say a Hybrid would yield better times at the track, as I said the Inejn gives me what I need, at the track I would benefit from the Hybrid more so.

D Love

Aren't track times all about the 60'? With our cars, a good 60' time will yield a good 1/4 mile time no matter what intake you have (hibrid/CAI) right? Since the CAI will give you more low end torque, wouldn't it be more beneficial to have the CAI in order to lower the 60' time?