VG swap air intake options

Problems, ideas and comments specific to engine swaps.
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tr6racer21
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Location: Richmond, VA

VG swap air intake options

Post by tr6racer21 »

Got the VG30 mounted and in the 510. I have been working on plumbing, exhaust, wiring, etc. One of the items that I'm not sure of or undecided upon is the configuration of the air intake, filter, and MAF prior to the throttle body. I would like to use the stock MAF which has a OD of 3 1/8" on both ends. The intake which is from a 200sx has the z31 throttle body on it(same diameter as the 200sx) has a diameter of 2 3/4". Most of the aftermarket air intake pieces and parts that I find from suppliers are sized for 3", 3 1/2",, 4" etc. I have seen various pictures of VG30 install using the 200sx intake, but have no idea what is done to get around the sizing issues.

The other challenge is that I will need to provide air supply for the PCV system and the idle air control valve. Spectre makes/supplies fittings so that you can drill a hole in the intake tube to accomplish this, but I haven't found other sources.

What filter media is preferred for this application as there seem to be many options?

Lastly I have read a few threads that claim decreased performance from the aftermarket air intakes. I know that they are louder due to no factory baffling, but not sure about the performance issues and what could be done about it given that the engine swap almost requires this form of air intake.

Thanks as always for your input.

Chip
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okayfine
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Re: VG swap air intake options

Post by okayfine »

tr6racer21 wrote:Lastly I have read a few threads that claim decreased performance from the aftermarket air intakes. I know that they are louder due to no factory baffling, but not sure about the performance issues and what could be done about it given that the engine swap almost requires this form of air intake.
For this and your air filter media question, you're probably better served looking up comparos done on the same dyno on the same day. Many of us have dynoed our cars, but not to the extent that we could tell which intake system or air filter type was best across all (or many) brands.

In my experience with Nissan engines, the factory exhausts are corked, but the intake tracts are reasonably open. Certainly changing out the KA/DE intake manifold for a set of ITBs didn't give me the magical 30HP the Internets kept saying it would. But putting on a 2.25" exhaust out the back did wake up the KA in ways the stock bits (240SX, exhaust, engine) never had.
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson
iceD
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Re: VG swap air intake options

Post by iceD »

I watched an episode of Wheeler Dealers of a Subaru WRX. After making exhaust and intake upgrades, on the dyno the car was down 15 HP. The dyno tech worked on the ecu and got back 35 HP. His reasoning was the ecu was reigning back the car because it was confused. I just checked it out on you tube but I don't know how to post it here. I'm not sure if a VG has an ecu but it is interesting.

ice D
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Heinrich
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Re: VG swap air intake options

Post by Heinrich »

i have been an bystander at a tuning company that a friends dad owned for years.
they specialized in Nissan , and 70% of that was vg30/33 cars.

8 out of 10 times the answer was simply to have as short as possible path, as few bends as possible , remove any corrugated plumbing as found on all stock Nissan and open up the factory air box witch they left in the factory position.
the extra air box opening should face to the front of the car.

this is not law, just my experience.
and all this was verified on a dyno with same day before and after readings.
Progress is slow, but it is progress non the less.
Three B's Racing
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Re: VG swap air intake options

Post by Three B's Racing »

EFI cars with any intake/exhaust mods will confuse the ECU like the tuner on Wheeler Dealers said. So a tuning is required for those gains your expecting + those extra gains from the tune itself and is well worth the $$$$ the tune will cost you.
"Lastnight the wife said oh boy when your dead you can't take nothing with you but your soul oh "Think"
- John Lennon
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