siug37

I just wanted to say one thing... This day and age newer cars will actually LOSE power when you add an intake and exhaust unless the car is properly tuned. Since we do NOT have any tuning devices available at this time, I would shy away from modifying the intake or exhaust.

Another reason why I would shy away from modifying the intake and exhaust is because nobody has done enough testing to see if the parts available actually help the car.

If someone wants to buy an intake and exhaust and dyno the car and show us the results.. great.. but I won't be buying anything until I see some proof.

inkum

I agree. Taking my Stillen intakes back. Big gaps in throttle response in various places using the full auto mode. Throttle response was better with stock. However, the engine "sound" is awesome.

siug37

Yeah the sound might be "awsome" but if it doesn't do anything for performance or makes the car worse.. why waste the money..

cyberjock4hire

Has there ever been a hand held tuner for these cars that plugs into the OBD2 port? I see places where you have to send in the whole computer module for tuning, but for me, I will not do that.
I had a 2005 Ford Mustang GT and you would just purchase a tuner, and you would purchase tunes from a well known performance place or get custom dyno tunes uploaded to this thing. from this unit you had the option of uploading a tune, based on fuel octane, engine performance metrics, and you could set it back to stock should need to take it to the dealer in the event they have the initiative to load the latest firmware updates.
With this device you were also able to select a tire size or rear gear ratio, so if you changed any of these items your speedo would be accurate.
Does anyone know if the G37 can be programmed via the OBD2 port? I would guess that the dealer plugs stuff into this port to do their diagnostics and reset the check engine light, so it seems possible.

siug37

I noticed that the G35 can use devices like a Utek for programming, but thats a piggy back ECU.. not a plug in OBD2 device. On my STi we had an accessport which did plug into the OBD2 port. Its just a matter of time until people start coming out with devices for us to use.

Edit: It looks like Cobb Tuning (big in the STi world) is making an accessport for the G35.. So I would assume one for the G37 is coming out. If they come out with something for the G37, I'll buy it in a heart beat.

http://www.cobbtuning.com/categories/?id=2215

Edit Again: I sent an email to Cobb asking if what their plans were.. Ill report what they say.

3des

In general a motor should not lose performance from a slight increase in airflow (intake or exhaust). I would think the HR would be capable of self-tuning to some degree to account for the increased air volume. This is the job of the MAF and as long as you don't modify that component or any of the air sensors, reducing restrictions should help. Massive changes in air volume produced from the likes of intake manifolds & headers would definitely need a tune but an intake? VVEL can surely deal with a little more airflow without special tuning...

siug37

In the STi world.. even an intake would cause the entire car to get retuned.

Blk-G35

This is part of reason why I'm leaning towards with keeping the stock intake box and swap out stock filter with K&N filter. After the filter swap I'll probably cut air inlet wide open to allow more air to come into the box freely.

Blk-G35

This is part of reason why I'm leaning towards with keeping the stock intake box and swap out stock filter with K&N filter. After the filter swap I'll probably cut air inlet wide open to allow more air to come into the box freely.

UNV-IT46

iTrader: (3)

a quality intake and exhaust system will always net more hp then oem. its also not always about making but loads of more power on a dyno. Its about changing the power points. You may only see a net gain of say 10hp overall but say at 6k rpm's your now making 20 hp more. its not always peak numbers

NJlakeshoreG

iTrader: (1)

good info to teach these young bucks unv!! lol.. let em know...

KAHBOOM

iTrader: (4)

The problem with many of the NA mods is that often they reduce low end performance. It might make up for it on the higher end of the revs but my experience is that you don't always gain enough up top to make up for low end loss. That's why I like the plennum mods. You get gains throughout the powerband without loss of torque down low.

NemesisG37

Do we lose power from the cone style filters? I dont see how something like the Z tube could lose power. It utilizes the stock intake box and just replaces the cheap plastic tube.

Part of the reason we gain power from intakes is because they are a straight thru design, w.o the stock intake silencing chamber(found on most stock intakes) and the increased diameter. Along with better materials, hence their ability to stay cooler.

I think the best intake for our cars is the most simple one, that is able to run with the stock intake box. Like the Z tube.

cvt

take this information for what it's worth:

i had an 03 350Z...stock it ran great. i decided to mod it with an intake and exhaust and it ran...okay, it was definately louder and throttle response was a little better. i decided i wanted a little more power....i got a crank pulley, plenum spacer and net 243whp...not bad, my a/f was a little leaner than stock but was still around the 13s. when i got my headers i still dyno'd at 243whp but now i was at 14.1s on the a/f ratio. my car was not as lively anymore as it did when i was stock. basically the mods that was supposed to help make my car breath better was causing erratic readings on the ecu and throwing off the a/f ratio...causing it to be very lean and not getting enough fuel. so at throttle the car wouldn't take off because it was pulling timing. i took it to technosquare and Tadashi pulled my pugs to find that i was indeed running lean AND i had aluminum parts on it! (i was apparently detonating). i got the reflash and she drove like a dream...no more hesitating, great pull thrughout the band, and a safe a/f ratio.

by far the ecu tune was the best hp mod i got. it made all the other mods come together!

this isn't like the cars of old when intakes net you 20whp! now cars are more efficient with complex ecus that control timing, opening TBs, air/fuel, etc...the ecu needs to be cracked to reap the benefits.

RedHerring

iTrader: (1)

Be careful with high flow air filters, especially K&N. They let dirt through. Do your research first.