JoeR

Oh, really again??

If the OEM intake DOES NOT impose any restriction, than please explain how any other can best that??

Not opinion, but data logged proof....



This is a pull with the OEM intake going above the factory redline. In the lower area, the purple line represents the manifold pressure. At full throttle, it flatlines all the way up. If it were in any way restrictive, manifold pressure would drop in the upper air demand regions. It does NOT!!

As for tuning, a good tune will put out more power than all of the above items mentioned. Been there, done that and tested.

RaineMan

I'm calling you on the HPTuners charts man.

For the stock airbox, or any airbox for that matter, to pose "no restriction" is impossible. If you are running a filter there is always some degree of restriction. Didn't the fact that you were seeing "no restriction" at the time seem just a tad bit odd to you? I mean come on... the engine is getting air from a rectangular paper filter inside a square sealed box with a little tube coming out one side.

Did you run it with the airbox completely removed and the throttle body exposed? That would be the definition of "no restriction".

Do you have a similar graph with a different intake installed, to show some differences?

With no other comparisons, a "this is stock" statement doesn't hold much water (or air).

I can tell you just from looking that the stock airbox and paper filter are absolute garbage. They are designed to keep things quiet under the hood, and that's about it.

There has been plenty of proof shown all over the place that products from manufacturers like K&N or Airaid flow more air than stock paper filters. Therefore they pose less restriction to airflow than the factory system does. This enables the engine to get air more freely, and thus, we have a slight power gain.

IF you are simply trying to say "In stock form, the intake and exhaust systems on the 2.4 are ideally suited for the volume of air that the engine can flow." you are certainly going about saying it all wrong.

Snoopy

This is the best way to go. It costs nothing and provides good cold air Additionally, the extra length of "tube" provides a RAM AIR effect.

RaineMan

Plus you get that wonderful salty potato smelling exhaust. Everyone will love you in traffic!

JoeR

Rainman... you stated, "...plenty of proof shown all over the place..."

Where?? The manufacturers' claims?

Ok, you know so much more about this topic, so I suggest you go with the "Snoopy intake"!!

hhrcrafty

I think the point of the graph was understanding that the stock airbox flows all the air the stock engine needs at maximum rpm and manifold pressure. So far, no independent testing has ever been done for any of the so-called CAI kits for the HHR. In fact, most bolt-ons for this car and every other car made in the last decade do require a tune in order to maximize the performance gains from those parts. Nobody is ever going to feel a 10 HP boost in performance in these cars. At most you're going to see 3-5 HP at the wheels without a tune, if that.

I thought the stock filter was fine on my HHR. It lasted 50,000 miles as advertised and still appeared clean on replacement. The intake tube from the fender to the box looked pretty dirty.

RaineMan

JoeR... you still have not shown any comparitive proof. All I see is a stock chart... to prove or disprove claims of any gains you have to provide some sort of before/after comparison.

The argument that "Stock is perfect. Therefore anything other than stock is bad." is invalid.

Hhrcrafty is making the same point I am trying to make. These kits claim 10hp gain at the max... it is not something you are going to feel, and nobody is using "ricer math" to say they picked up a few tenths off of an intake. If the stock box flows enough for the stock engine, who says the engine is going to stay stock? To gain any kind of performance at all you have to start changing things somewhere.

Tuning to take advantage of increased airflow as a result of modification is a given... but you keep acting like there is no point in doing the mods at all. There is a difference (if ever so slight) between 10hp and 0hp.

Just because you had the spare cash laying around to slap a M62 on the front of this thing and do some tuning does not make you a god around here... but that is exactly how you act. Until you provide some detailed comparitive results you aren't going to convince me that I would be better off flushing my money down the toilet.

hhrcrafty

Actually, it does make JoeR a god around here because he's one of the few people that's done anything to the car to radically improve performance

One question I would have about the flatlining of the MAP curve is whether or not that's actually a limitation of the stock programming rather than evidence of the superior flow rate of the stock intake box. From the very little bit of knowledge I've gleaned from a tuning book I read, the tables in the computer calculate the MAP based on parameters gleaned from MAF output. If the MAF output is maxed out due to the limitations of the stock sensor, doesn't that mean that the stock programming isn't taking advantage of increased airflow into the engine?

I am NOT an engineer, so if I'm reading this wrong, please correct me.

IgottaWoody

http://www.bobistheoilguy.com/index....d=58&Itemid=66
Dabble on this...a comparison of sorts in the real world..I'd say it WAS the piping that made the difference

Hib Halverson

I've posted several times to this thread but, this time, I wanted to get more in-depth on airboxes.

I've been toying with them on my HHR for a while. Last year I tested the Airaid but that didn't end well because the product had fit problems. Those having read other HHR Network threads to which I've posted...
https://www.chevyhhr.net/forums/show...=Airaid&page=2
https://www.chevyhhr.net/forums/show...ghlight=Airaid
https://www.chevyhhr.net/forums/show...=Airaid&page=2
...know my first attempt at testing an airbox came with the Airaid Intake Kit (PN 200-195). That ended prematurely when I learned (to the manufacturer's surprise, too) that the Airaid unit does not fit five-speed HHRs because the rear wall of the box interferes with the truck's cowl. Now, some have said, "Why not cut the cowl for clearance?" and that's one way to solve the problem, however my contention is that a product, such as an airbox, should be a bolt-on fit. Airaid apparently agrees with me as it changed it's application data to state, in bold letters, that their kit "fits automatics only!".

I didn't determine the specifics of why the Airaid box has an interference problem on five-speed trucks, I suggest it's one of two problems: 1) (possible) the powertrain in a manual is mounted slightly rearwards from where the automatic powertrain mounts or 2) (likely) the manual powertrain is tilted slightly more to the rear than that of the auto. In any event, the Airaid fit problem had me removing the parts, selling them on Craig's list to an automatic owner.



After asking about the K&N intake kit here several months ago, I decided to test one on my '07, five-speed. More correctly, this product is a "Fuel Injection Performance Kit" (FIPK) and is part of a line of air intake products that K&N has marketed since the early-'90s.

I put an FIPK on my S-10 Blazer early this decade, so I was familiar with how K&N Engineering did its intake kits. I contacted Bert Heck, K&N's Product Manger for FIPKs, and found the company had never tried an installation on a manual trans HHR and was anxious to do a fit and test session.

At 7:30 AM one morning a few weeks later, I presented myself and my HHR at K&N Engineering in Riverside, California. Dynamometer Test Technician Kirk Swanson had a Fuel Injection Performance Kit (PN 57-3056) ready to go.



After strapping my truck on K&N's DynoJet, inertia-type, chassis dynamometer, the first thing Kirk did was "baseline" the truck by making three runs. Mods already installed were a Green Filter in the stock air filter assembly, a Flowmaster exhaust system, Denso IVT-20 spark plugs, Red Line Synthetic 10W30 engine oil and Red Line Superlight Shockproof transaxle lubricant. The truck with those mods averaged 148.4 horsepower at 6050 rpm and 142.4 lbs/ft torque at 5150 rpm, SAE-corrected, at the front wheels.



It took Kirk all of 30 minutes to install the FIPK and that was with me occasionally stopping his work to take a photo. Most DIYs with basic mechanical skills can install this product on HHRs using common hand tools in about the same time or less.









I think one feature which sets the K&N FIPK apart from the Airaid and GM Performance Parts intake kits for HHRs is that the airbox is made from high-density polyethylene (HDPE) plastic rather than sheet metal. While the tooling costs are higher for parts made from HDPE, K&N chooses that material because 1) it has 15 years experience using it for aftermarket air filter assemblies and 2) HDPE is a better thermal insulator than sheet metal, so it slows the rate of heat transfer into the box. Another feature which I like about the K&N is the airbox's compact size. It doesn't cover the most of the engine as does the stock box, the Airaid or the GMPP. Lastly, unlike the Airaid, which is open to hot, underhood air at the front, the K&N, once the lid is screwed in place and the cold air duct reconnected, encloses the filter.









The only weakness of the FIPK, in my opinion, is its written instructions have images so small, that most people will need a magnifying glass to see detail in the images, if they need the pictures to help them install the kit. K&N's airbox for HHRs is a premium product and needs a little better imagery in the instructions.

With the FIPK installed, my HHR averaged 156.3-hp@6100-rpm and 147.5-lbs/ft@5160-rpm. The best run was the second one at 156.7-hp@6200-rpm and 148.0-lbs/ft torque@5100-rpm. K&N's Fuel Injection Performance Kit increased peak power, on-average, by 7.9-hp and peak torque by 6 lbs/ft.



Looking at the data we obtained in the sessions on K&N's Dynojet, I have a couple of other observations. First, the FIPK's influence on torque output becomes noticeable as low as 3700 rpm. From 3700 to 4200, there's a bubble of extra torque and another from 4500 to 4800. At 5200, the significant increase begins and extends to the engine's rev limiter.

Second, based on some comments I've seen on the HHR Network and other sites, some owners believe that the intake air duct–some call it the "Wooly Worm Tube"–which runs from the right front fender to the airbox, is a restriction. We tested my truck with the duct connected and disconnected on both the stock and the K&N airboxes. There was no practical difference in performance, so we can assume the air duct is not a restriction at range of power levels a 2.4 with modest bolt-on modifications will run.



Third, during testing, the air/fuel ratio was about 13.7:1 from 3000 rpm and up. It's clear that, after mods to both the exhaust and intake, my engine is running a bit lean at wide-open throttle, so the next thing I do is some custom ECM programming. Getting the AFR at WOT down to 12.5-12.7 at 3000 rpm will probably further improve performance.