SPT Ram Air Intake

[awdpapi]

Hi!!! Currently I have an AEM system in my car and i was told the SPT system gives me better performence and Horsepower. Any advices???

[Drew84]

I like the Cobb SF intake, it doesn't abosorb heat like the metal SPT.

[schrags]

Intakes are really only good for sound if you are pushing under 400hp, no real performance increase. Aftermarket intakes actually do the opposite by generating air turbulence, causing a misreading on the MAF. Is it recommended that unless you are pushing 400+hp, then just use the stock intake. If you want the sound, then go with one of the following.

Which intakes do not cause problems with the air/fuel ratio? The only manufacturers of intakes that claim in writing not to cause any ill effects are:
a. TurboXS (http://www.turboxs.com/txs_intake.htm)
b. APS (http://www.airpowersystems.com.au/wrx/my01/hfa.htm)
c. Perrin (http://www.perrinperformance.com/products/intake/intakes.htm) (based on my personal email correspondance with Perrin)
d. K&N Typhoon (http://www.knfilterchargers.com/search/product.aspx?Prod=69-8001TWR) (based on testing (http://forums.nasioc.com/forums/showthread.php?t=590315) by nhluhr and testing (http://forums.nasioc.com/forums/showthread.php?t=658632) by AaronWRX, both NASIOC members) These tests were performed on an STi and their effect on WRX A/F ratios is untested.
e. Cobb Tuning (http://www.cobbtuning.com/)
f. SPT (http://www.subaru.com/microsites/spt/main.jsp)http://forums.nasioc.com/forums/showthread.php?s=&threadid=477393

[Blix666]

i've got an ebay short ram and it sounds cool. $30. no mis-reads or codes thrown.

[IMPREZV1]

I am currently running the SPT and have had no problems with it. Got to love the sound for sure. The wife loves the woosh sound haha.

[martinus]

I like the Cobb SF intake, it doesn't abosorb heat like the metal SPT.


Seriously doubt the air has time ( driving ) to warm in there ... uless you are @ a traffic light ...

[Blix666]

Seriously doubt the air has time ( driving ) to warm in there ... uless you are @ a traffic light ...


i think we need to contact Mythbusters on this one. this is an argument i've seen/heard time and time again with inconclusive endings.

maybe they could do an "illegal street racing mods and do they actually work?" episode!

see: http://www.dirtyimpreza.com/forums/showthread.php?t=1766

[lorenkb]

Seriously doubt the air has time ( driving ) to warm in there ... uless you are @ a traffic light ...

After back to back rallyx laps I'd say the short ram has had plenty of time to heat up. More importantly, any air that thing is pulling in is pre-heated as well. There isn't a whole lot of fresh air coming through the engine bay at the speeds we see in rallyx.

It's been noted here (http://forums.nasioc.com/forums/showpost.php?p=16867293&postcount=253) how short rams behave with no airflow and cold outside temps. I don't see them behaving much different on a hotter day with rallyx speeds.

[martinus]

Was talking about an actual CIA, metal vs. plactic ... if ts a measuarble diference and its a significant one is prolly just a maketting gimmic. Looks like we all agree, short rams are a waste of money, esp. in a turbo car . ( hotter engine bay )

[Qman]

i think we need to contact Mythbusters on this one. this is an argument i've seen/heard time and time again with inconclusive endings.

maybe they could do an "illegal street racing mods and do they actually work?" episode!

see: http://www.dirtyimpreza.com/forums/showthread.php?t=1766

Funny you should bring this up. My local shop has an all-wheel dyno and we were messing around with one of the employees cars. A '93 fwd Impreza wagon. Ran a base pull at 62whp. A second pull while using a gas powered leaf blower blowing through the intake tube. Increased to 68whp. Now for kicks one of the customers Mom's had bought him a "Tornado". We installed it and believe it or not it increase stock numbers by 6-8hp and 4wtq. I wouldn't have believed it had I not been standing there while he ran it.

But, back to the intake question. We have been playing with a few N/A cars there including mine. These are the results.
2000 2.5RS 130whp
1999 Outback wagon with auto trans, acceleration cams and Perfect Power 6 put down 143.
1996 Brighton(running a '98 2.5RS ECU)2001 2.5 phase2 with Delta regound torque cams, OBX equal length headers and exhaust, SPT intake that has been shortened, and Perfect Power 6 piggyback. 160whp and 158wtq. That works out to being about 208 bhp which isn't too bad for a N/A car that doubles as a DD as well.

My long-winded point is this...

To get more power requires a number of steps. Simple formula is that the more air you bring in the more you have to get out. Mods need to be done in series. The intake will make a small difference by itself but more when done with other mods that support the theory of more in more out.

[Drew84]

From Cobb's Website. I kinda believe them. Their cars are proven power makers. I don't like cold air intakes because water can be easily sucked into the engine. I've also been told its an easier piece to tune with on the car.

The COBB Tuning SF Intake utilizes our custom design to maintain optimal flow and net the ideal performance while remaining unedited from the factory velocity stack. The custom conical cloth filter feeds filtered air directly to the engine, while maintaining optimal intake velocity and minimizing turbulence found with many aftermarket intake systems. The COBB Tuning SF Intake system is compatible with Stage 1 and Stage 2 OTS (off the shelf mapping) provided for our AccessPORT ecu tuning device.

Our system utilizes several unique features in an effort to maintain optimal flow for performance while minimizing turbulence that can cause engine management problems. From a custom conical cloth air-filter element, we use a CFD-designed velocity stack leading to an unique air flow straightener grid. This straightener grid is specifically designed to smooth the incoming air flow as it passes the Mass Air Flow sensor for precise readings. This eliminates the "dead spots" experienced by other aftermarket intakes due to turbulence. NO other aftermarket Subaru intake system utilizes these critical design elements.

In order to provide a system that looks as good on the outside as the technical advancements happening on the inside, we utilize a one piece design constructed from a high temperature plastic composite. Not only does this save weight compared to the previous metal design, the plastic composite material offers much better heat rejection properties that help keep intake air temperatures cooler. In contrast, intake systems constructed using metal castings or piping can actually retain underhood heat and in turn heat the incoming air.

[lorenkb]

I have no objections to what COBB has said (well, I might have issues with their CFD...). That said, I think they are missing the primary downfall of a short ram, especially in our case of low speeds and high RPMs: the air inside the engine bays is going to be damned hot, and that is the only air available when using a short ram. Having a metal housing that can heat soak is going to make matters worse, but they've only solved half the problem.

FWIW I don't like CAI intakes either because of the water issue. The stock intake does its job quite well.

[awdpapi]

Thanks for the advices!!! I think I'll go with TURBOXS. I already have the UTEC and full exhaust system from them anyway.

[Drew84]

Yeah the stocker does do a really good job, but you can't hear the turbo spool and theres no fun in that.

[awdpapi]

Super agreed!!!!!!!!!!!!!!!!!!

[fattie92]

I have my eye on a Injen CAI. My shop might end up being a distributor, so I can possibly get it cheap. They look nice, and claim it does not need a re-tune.

[Blix666]

i dunno fattie, that might be too ghetto :flamed

[fattie92]

i dunno fattie, that might be too ghetto :flamed


This is true.... Ah fuk it! :FU:

[awdpapi]

^:waving::mrgreen::lol2:;-)!!!!!!!