Will these affect the performance of a stock FI 2.0L engine negatively in any way?

Regards'

Jon

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K&N. One of Capn' Krustys' faves.

Yeah I know the K&N battle, but does anybody run these things? I'm more or less questioning the vacuum line hook ups and vacuum effecting FI performance. Not so much if K&N is a good air filter.

Jon

I used them on my 3.2 (yellow zonker) and I use them on my other car with Webers. Work fine for me. I'm sure others will disagree. But then again, I use high temp silicone to seal and secure my push rod tubes so what the hell do I know?

The only time I would use a K&N is when a paper filter won't fit an application. K&Ns allow bunches more air in but only because they filter less which also means they let in trash. If a K&N is your only option make sure you clean it regularly and keep it oiled. If its on a newer car that runs a MAF sensor a K&N will trash it in short order.

Jon,

Any of the lines forward of the throttle body are not vacuum - they're open to atmosphere. They should not affect FI performance. The only lines that can are those after the throttle valve.

Aahhhh, the age old question of getting better air intake into the 914 engine.

I always wonder if you could get air piped in all the way from the front of the car.

We built a single intake system, and a dual intake system (pictured) for this application. This system has been proven on the track with multiple Porsche Owners Club class wins and perfect for the street as well.

The FI doesn't really care exactly where its lines are hooked up. It just needs specific hoses to either be hooked to manifold vacuum, or to ambient-pressure (filtered) air. So as long as you hook up the hoses that used to go to the air cleaner to something "upstream" of the throttle body, you're fine.

(The exceptions to only manifold vacuum or ambient air are the lines from the throttle body to the distributor dashpot. But those don't enter into this discussion anyway.)

--DD

I ran K&N's on my 72 with 44 Webers and had a lot of issues with clogged idle jets so I added the K&N pre-chargers and that solved my issues. I'm going the same route for my -6

Thanks for the replies. Not sure though if I will make the purchase. After all, it really only looks better then the OEM filter housing.

Jon