# Air filter directly on turbo?



## andrew186 (May 3, 2010)

Hi guys

I recently purchased a R34 GTR and it has an air filter directly on the single turbo, I'm wondering how many here run that type of set up and if there are any potential problems? 

It sits quite close to the engine itself










For what it's worth I will be installing a small heat shield but would like to know if people here run anything similar on their RB's .. The previous owner hardly did any miles so I'm afraid long term problems (if any) might not have surfaced yet


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## R32 Combat (Jan 29, 2004)

It's not uncommon to do that. You'd be a little better of moving the air filter forward and into the inner wing a little.


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## matt j (Oct 19, 2001)

Another factor to consider is that putting any bend in the intake will significantly effect the air supply to the engine. We did a lot of testing with different setups and all impeded flow and restricted the engine.


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## tarmac terror (Jul 16, 2003)

There's absolutely no problem with that....

Providing a cold air feed and boxing off (if possible) will both help with intake temp issues..


TT


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## D-Ranged (Aug 16, 2007)

matt j said:


> Another factor to consider is that putting any bend in the intake will significantly effect the air supply to the engine. We did a lot of testing with different setups and all impeded flow and restricted the engine.


Interesting i didnt know that. I had my filter on the turbo but then went to a 45 degree bend and put it down in the wing.


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## R32 Combat (Jan 29, 2004)

D-Ranged said:


> Interesting i didnt know that. I had my filter on the turbo but then went to a 45 degree bend and put it down in the wing.


I used a 6" outlet K&N filter, a 6" bend into a 6"-4" bell mouth which was fitted to my turbo.

Unlike Matt, I did not instrument the system, measuring the pressure along the pipe, air density, speed etc.

I just bought what I could from Demon Tweeks. It looked like this


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## TAZZMAXX (Mar 9, 2010)

matt j said:


> Another factor to consider is that putting any bend in the intake will significantly effect the air supply to the engine. We did a lot of testing with different setups and all impeded flow and restricted the engine.


I'd have thought that the horrible 90 degree bend on the compressor outlet would do more harm to air flow than putting a slight bend on the inlet to it.


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## matt j (Oct 19, 2001)

Try it on the dyno and log the results...

When the new dyno is installed, I'm also going to get quite a few comparisons of different parts. If there's interest, I'll share the results.


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## Jayman (Jun 30, 2012)

Very interesting, i shall do this and post the results when mapping the car this coming month.
I must say there are alot of factors to consider: type of air filter, the inlet of the airfilter if its shielded where the feed is coming from! etc etc etc.

My doubt of the results comes as I did a similar experiment with a mercedes 3.0 6cyl diesel engine, where i tried numerous different air filters ranging from cheap ebay crap to ITG and K&N, the K&N was simply the best by a long way. It let minimal dirt through the filter and made no difference to power weather it was attached to the turbo or not at all. Infact the ITG let dust and fine particles through and had a loss of 2whp compared to the K&N. As for the ebay enclosed filter, well that created a 30whp loss and 25 ft ibs at the wheels loss. 
what I didnt try was creating a "bend" between the filter and the turbo, i will try this and see if there is any difference at all, whilst i dont doubt your test vehicle showed a difference I find it very hard to believe that there will be a significant loss due to my previous tests.

This could be interesting.

Regards 
James


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