Finally: Dyno charts of de-snorked 986S!!!

[Bisimoto]

Greetings all,
I recently purchased my 2001 Boxster S (last week Wednesday), and could not wait to start playing around with it on my dynamometer. I am an engineer, tuner and enthusiast, and have designed parts for NSXs, S2000s, and even factory supported FWD drag race teams. My race program involved many secured world records...but I digress.

Since I own my own Dynapack Chassis dynamometer, and noticed some confusion in this board (yes, I have lurked for a while) in regard to if de-snorking produces any other benefit above an enhance intake roar, I took it upon my self to perform the following test. Each run was repeated to ensure credibility.

My bone stock S: red line
De-snorked (15 minuets later): violet line



A 5 WHP GAIN!!!! In addition, almost 3 ft/lbs of torque

Finally some proof, and feel free to share this with our peer members. This is the most cost effective gain I have seen in a while!

On the dyno:



Left over "organ":




No tyre interface to introduce, variables like other cheaper intertia dynos. More data to come, as I try some interesting technology on the S...

You lucky son of a gun, how much did that dyno cost you? I presume thousands...
Im glad you did the dyno's, all you need to do now is test some other stuff like a cold air intake, or exhaust.

[Bisimoto]

The unit set me back $61K, but worth every penny: more accurate and safer than inertial roller dynos. Since K&N is helping my race program this year, I will have to get a filter for the Boxster and test that too.

I design my own headers and exhaust systems for my race cars and many inline 4 vehicles, and will soon embark on making some for my S. When I spent some time studying the undercarriage earlier today, I noticed that the factory exhaust system is in dire need of some improved breathing! More ponies to come!!

Thats a lot of money. But if you design your own exhaust systems and headers, Id suggest making short equal length headers and gradually make your way to the longer "racing" style headers. That way we can see if there is a linear form to flow vs backpressure needs and where the optimal points are.

[Bisimoto]

You are amazing, Jonathan. There is so much power in header tuning, it is mind boggling. I have data on your suggestion, and found out that high performance engines hate back pressure, but require fuel and ignition optimization for improved efficiency and power: the main reasons my simply reducing BP sometime results in power loss. I look forward doing some primary length tests on each bank using a true "burns-style" merge collector.

[blue2000s]

Originally Posted by Bisimoto

You are amazing, Jonathan. There is so much power in header tuning, it is mind boggling. I have data on your suggestion, and found out that high performance engines hate back pressure, but require fuel and ignition optimization for improved efficiency and power: the main reasons my simply reducing BP sometime results in power loss. I look forward doing some primary length tests on each bank using a true "burns-style" merge collector.

There's also the scavaging effects of the right length of pipe.

It'll be fun to see what you learn while playing with the car and the dyno.

[Bisimoto]

Originally Posted by blue2000s

There's also the scavaging effects of the right length of pipe.

It'll be fun to see what you learn while playing with the car and the dyno.

Very true, Blue. You can also enhance that with pipe ID steps, and preventing reversion at the flange helps a bunch as well. Despite what I see in the market for the boxsters, a long primary tube may prove to be a best bet due to the relatively low peak power RPM of the boxster engine. Most units I design for 9800+ rpm engines have primary lengths that hover in the 20 inch range.

[blue2000s]

Originally Posted by Bisimoto

Very true, Blue. You can also enhance that with pipe ID steps, and preventing reversion at the flange helps a bunch as well. Despite what I see in the market for the boxsters, a long primary tube may prove to be a best bet due to the relatively low peak power RPM of the boxster engine. Most units I design for 9800+ rpm engines have primary lengths that hover in the 20 inch range.

Do you do any modeling with software tools? Wave, GT-Power? You can get close to optimal much faster with some well designed models.

[Cloudsurfer]

Bisimoto-

Welcome to the board and thank you. I think alot of us have been waiting for a true engineer and enthusiast to come along and do a few things right. Theres no doubt that the factory 3.2 is a somewhat detuned motor to keep the Porsche pecking order intact at the dealership, but it would seem that the key to coaxing more power out of the 3.2 lies in DME tuning, not just bolt on bits to help the motor breathe better.

I am very interested in finding the right headers (preferably with integral high flow (200 cell ideally) cats and 2nd cat deletes. On a motor of this expense, I'm not sure I trust running any of the higher flow filters or intakes due to the increased amount of grit that gets by, by figure a de-snorked stock intake. Now if someone can make a fantastic map to flash into the DME to take advantage of this and 93 octane fuel (or better) I think that would be a real winner.

Good luck to you and keep us posted.

Patrick

[Bavarian Motorist]

I just looked on caymanclub.com for desnorking.

I'm still not sure what it is. All I got is that there is an extra air restriction on the car somewhere.


Can anyone explain what it is briefly?