Stock airbox intake flow (pics)

[SpIcEz]

Originally Posted by tommy583

That basically looks like the EVO intake Fabspeed used to sell, only now more expensive. It still doesn't seal the engine bay from the filter section. That rubber on the top edge is below where the top cover will be, it will never seal like that. Why can't they just make it a sealed box with some kind of air tight door to service the filter? Why does it have to cost so much? I mean really $500 for a piece of metal, a foot of plastic tube and a cone filter.

I agree the price is quite outrageous.

As for sealing, I dont think its a problem. If you find it doesnt seat well, you could add foam or something else under the rubber seal to make it tighter.

But, honestly, to me it just demonstrates all the naysayers saying you NEED a stock airbox to make power are saying nonsense.

There is nothing magical about their design. And the M96 works just like 100% of all engines out there. Less restriction = more power.

They show considerable gains on that dyno. Now, on the other hand, I'm sure you wont get that in all conditions. Especially on a hot day when things are heat soaked.

I can build one like that, only thing is to find a MAF flange for 986/996 MAF sensor to weld on a suitable aluminium pipe.

[Tremonte986]

Originally Posted by SpIcEz

I agree the price is quite outrageous.

I can build one like that, only thing is to find a MAF flange for 986/996 MAF sensor to weld on a suitable aluminium pipe.

EZ-PZ....

https://shop.advanceautoparts.com/p/spectre-mass-air-flow-sensor-adapter-87051/11430025-p?c3ch=PLA&c3nid=11430025-P&adtype=pla_with_promotion&product_channel=online&store_code=&gclid=CjwKCAiAhJTyBRAvEiwAln2qB3I459So1fmiJ8C87j9N 4NnnrZZOKqzM7L05jwpSLgje1VT4aKsCthoCx4MQAvD_BwE&gclsrc=aw.ds

You can get MAF housings cheap. Bolt on plastic configuration, or the aluminum like above.

[Topless]

It's easy to overthink this stuff and get sucked into the marketing hype vortex.

Back in 2005 there was a lot of independent dyno testing going on to compare different intake airbox designs. The airbox should do 2 things well: Let plenty of cold air in while keeping the hot air and bad stuff out. As I recall these were the basic results after a LOT of testing:

Stock 986 airbox worked fine on a 2.5L

987 airbox added 1-2hp primarily on 3.2L models

Cone style EVO filter inside the engine compartment lost 2-3hp due to higher intake temps, and rapid oiling of the MAF sensor caused the engine to run poorly. It was discontinued.

Boxster Spec Race cars all run stock 986 box and (I think) stock paper filters.