Arguments are much more fun without facts and science involved.

 

Your argument only confirms my statement: “Peak power cannot be changed using only an intake (in any engine) unless the change increases the volume of oxygen to the cylinders”. At mid range engine speeds, as I stated here many times, the velocity of air is increased using your intake which marginally improves VE. By definition, this means more air/fuel is getting into the cylinders.

And, if you assume that the amount of fuel mixed with air waiting to enter the cylinder is based on sound Porsche engine design and is predetermined based on intake design and operating parameters, you have now pushed a leaner mixture into each cylinder.

However, at or near top engine speed, the increased velocity of intake air no longer plays a role in improved VE mainly due to the crossover intake design as well as the intake valves becoming restrictive. Therefore, little to no additional mixture is getting into the cylinders. That is why there is no gain in peak power resulting from the intake change. If that was not he case, there would be immediate peak power gains after installing the intake and no reset of the ECU would be required.

Most of your argument makes sense for FI engines but not NA. Sucking air into an engine is a lot different than pushing the air into an engine as far as flow characteritics and laws go. This may answer your question as to why many of us are only referencing NA engines.

BTW: Many of us already use a cut off switch for the battery in our computer controlled performance cars.

 

I assume the amount of fuel mixed with air waiting to enter the cylinder is based on a fuel map that takes into account the air to fuel ratio measured by the O2 sensor. Theres no reason a modern (non carburated engine) should go lean unless its way out of its adjustment range (corrected lambda), in which case it would knock.

Any data to back that up? Because we have lots to back up our claim. See the dyno graphs.

[quote=1999Porsche911;1884447] Most of your argument makes sense for FI engines but not NA. Sucking air into an engine is a lot different than pushing the air into an engine as far as flow characteritics and laws go. This may answer your question as to why many of us are only referencing NA engines. [/quote]

When you put pencil to paper you realize that air velocity and density are just variables in the equation. Flow characteristics and laws are pretty much universal constants. There are two basic types of flow (laminar and turbulent) which are calculated based on the Reynolds number. How are you calculating your Reynolds number? What assumptions are you making about kinematic viscosity of air?

 

Then you don't understand the Porsche' computer while running open loop. At WOT, the primary conrtol of fuel is the MAF reading. 02 sensors do not come into play. Since the MAF reading is the same as stock, the amount of fuel injected is the same. However, your claim that the VE is increased requires more air to get into the mix. Therefore, you are leaning out the mixture.

Running lean will NOT cause the engine to knock until it gets to an extreme.

 

I'm amazed at how much energy some of you will spend trying to knock on a performance product claiming gains. If you don't believe the product adds power and that the dyno operator is just using trickery to show gains, then don't buy one and move on.. Let those who believe to believe... I had one in my 997S and it felt stronger, now if it was just from a power curve or actual gains in mid range I don't know but it wasn't like it cost that much for me to have one.... On a side note I sold my C2S and have a Plenum for-sale. I have it list in the sale section..

 

The MAF sensor is the primary control of the fuel map and the O2 sensor is a modifier. If the O2 levels are off, the computer uses a "corrected lambda" to adjust the fuel mixture. This is how porsche's (and all cars) are able to compensate for air density changes at different ambient conditions.

I'm a bit confused on how more air flow at high RPM will not be sensed by an air flow gauge. We're dealing with a closed loop system that has no air loss between the MAF sensor and intake valve, so if the intake valve is seeing more air the MAF sensor is detecting it.

The funny thing with forums is that you can never "win." These conversations get dragged on until one person gets tired of arguing and the other person thinks he's right. I think its best to let the dyno graphs and the happy customers do the talking. Technical questions are a bit different from bickering among non-believers. If there are any technical questions feel free to post.

 

Research what the difference between open loop and closed loop is. At WOT, you are running in open loop. In open loop, the 02 sensors DO NOT make any adjustment for mixture....period. If in open loop, your MAF is reading more air than is actually getting to the engine, you run rich. If it reads less air than is getting to the engine, you run lean.

As a tuner, I would expect that you would understand such a simple concept expecially when you are trying to justify the benefits of your product.

This is not about winning or losing but about putting out accurate information and letting others make their own decisions based on the information.

Jim

 

RSS would like to say that we appreciate all these highly technical debates over the past few days. It’s always healthy to keep any manufacturer honest so as to minimize the inferior products that finds its way to the market place. We can go on and on with more tech talk until we’ve bored 99% of the members here on the forum but the bottom line is that most of us are here because we’re driving enthusiast’s not automotive engineers.

RSS has stepped up to the plate like no other manufacturer ever has here on 6 Speed. Although hundreds of happy customers continue to praise the performance provided by their IPD plenums there were still some nay-sayers and non-believers who insist otherwise. Some people have their mind made up and there isn’t anything else we can do to change it. Just like a Democrat isn’t going to convert a Republican, a Catholic isn’t going to convert a Jew and I’m not going to convince my girlfriend to surrender the booty.

6 Speeders wanted and received all of the following…

Dynos
Independent Dynos
Magazine Reviews
Independent Dynos on Bone Stock Cars
Previews of our Facilities
IPD Plenum Dyno Day
Independent Member Testing
Open Public Testing

Again, the only thing left for us to do is start up an operation similar to a windshield repair facility where we come to your work or home with a portable dyno and perform the install while you wait.

The IPD plenum not only makes power, it makes great power and it makes it across the entire power band, especially in the mid range. If you don’t believe the plenum delivers the power we claim then don’t buy it. If you’re on the fence and still aren’t sure, then install an IPD plenum a see for yourself, if you’re not satisfied then return it for a 100% money back guarantee. If you are one of the many satisfied IPD customers then thank you for all your continued support.

RSS isn’t a glorified garage that recently jumped on the Porsche band wagon. We’re a 30,000 square foot facility that is dedicated to manufacturing, distributing and installing only the highest quality European performance products available. Just about everyone here has Porsche racing background and Porsche is our focus. If you are looking for the ultimate in Porsche performance give us a call.



Cheers,
Greg @ RSS

 

It would make me pretty nervous having any tuning done by you guys after you demonstrated that you don't even know the basics of open and closed loop. Anyone can reset their ECU and get more power by leaning out an otherwise rich running engine.

Why haven't you responded to the open loop comment? Running away from a civilized debate because you don't have the answers only raises more questions about whether you know what you are doing or not.

You have been selective in which dyno's you accept as accurate even tho other's have shown no power gains? Why?

I don't think we have bored 99% of the people here. I think many of them properly question the power gains you claim, as they should. Short of any sensable explaination as to where the power is coming from, why would anyone accept your claims? We all can reset our computer for substantially less than $1,000.

 

There's no harm in having an open forum discussion. Let it be.

 

At some point, we all have to take a leap of faith in a product. My conclusion, based on some of readings of the plenum thread posted across forums here at 6speed, tells me that I wouldn't hesitate to buy one from my local guy Cantrell Motorsport per the recommendation of Greg @ RSS to "plenumize" my C4S.

Everyone should know that YOU ARE infamous for taking up technical arguments with the highest visibility given to your claim that 15w is proper oil weight for the M96 engine which is absolutely ludicrous. Then you switched up your 15w to saying 5w is awesome and have always continued to insist that Mobil 1 0w-40 is "water" for the engine, that it's bad for the engine when in fact it's CLEARLY on Porsche's approved oils list.

So bottom line, what I've come to determine and am willing to blurt out that someone like Greg will not because he is doing business here... is that... You're weird, dude. But pls continue... you entertain me.

Thanks, RSS. I'll be looking to install the plenum soon on my car.

 

I' glad you follow all my posts. I hope you are learning something. BTW: I never, ever said that 5W was awesome.

 

Have your own dynoday and prove your point.

 

/signed

 

Just like your pointless posts that go no where here, you may have not typed the letters a-w-e-s-o-m-e, but ya sure did make the claim that 5w is better than 0w when in fact both are listed as approved oil weights on Porsche's list with 15w maple syrup NO WHERE TO BE FOUND which you absolutely adored and recommended to others.

And I see your posts cuz of your 1999 name at Rennlist and here, but honestly it's like reading War and Peace... no one ever reads the whole thing.

Dude, it's like do you ever try to take a look at the big picture, man? Seriously, if you sprinkled some reality to your technical knowledge, you actually may have people who would enjoy some of that 1999 pie.