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How much difference (HP) with a new air filter?

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Old Jul 17, 2002 | 11:31 AM
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How much difference (HP) with a new air filter?

Hi everybody,

Does anybody know how much difference a new intake air filter makes on a 89 TII? I´ve been looking at stuff like the HKS Super mega flow.

I already have a Racing Beat exhaust and boost controller...

Thanks!

Regards
Babu
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Old Jul 17, 2002 | 12:05 PM
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Re: How much difference (HP) with a new air filter?

Originally posted by villeman
Hi everybody,

Does anybody know how much difference a new intake air filter makes on a 89 TII? I´ve been looking at stuff like the HKS Super mega flow.

I already have a Racing Beat exhaust and boost controller...

Thanks!

Regards
Babu
An air filter is the cheapest reliable mod IMO. BUT the HKS unit SUCKS BIG HAIRY FRENCH GOAT *****...

...Get the Bonez/Apexi/K&N cone or a Blitz...
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Old Jul 17, 2002 | 01:24 PM
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if you get a good one, it's like 1-2 RWHP
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Old Jul 17, 2002 | 01:36 PM
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Re: How much difference (HP) with a new air filter?

Originally posted by villeman
Hi everybody,

Does anybody know how much difference a new intake air filter makes on a 89 TII? I´ve been looking at stuff like the HKS Super mega flow.

I already have a Racing Beat exhaust and boost controller...

Thanks!

Regards
Babu
do you know how much boost you are running? do you have a FCD? a racing beat exhuast and an air filter will cause you to run too much boost. and make it unsafe unless you add more fuel.
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Old Jul 17, 2002 | 01:36 PM
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The HKS is garbage - one of the guys at RP told me his had pieces of foam breaking off into his TID.
Get the Bonez or something else...

You're not going to see much gain until you free up the exhaust some - that's where the power is, but you'll need to start doing something for fuel around that stage.
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Old Jul 17, 2002 | 01:37 PM
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The K&N and Apexi, are 1000% better for a street driven vehicle.

Foam is great for the track, but a very poor street use filter.
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Old Jul 17, 2002 | 01:59 PM
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Thanks guys!

I guess I´ll go with the Apexi...

BTW. I had the cat removed.


How many HP´s (roughly) does the following config. give with approx. 8 psi boost?

89TII
Racing Beat exhaust without cat.
Racing Beat boost controller
(The Racinng Beat stuff is from -92)
Apexi air filter, which I´m about to get.

Thanks again!
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Old Jul 17, 2002 | 02:06 PM
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The HKS is a great product...it only costs about $130 and it looks great in my friend's garage on the floor, because I replaced it with a $20 filter. My AFM was completely black after having the HKS on there for a while.
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Old Jul 17, 2002 | 02:09 PM
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Is there any way of replacing the foam element with something else that won't break up?...this was installed on the car when I got it and it still has the same foam element since I got it(1 1/2 years).
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Old Jul 17, 2002 | 02:11 PM
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Nope.
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Old Jul 17, 2002 | 02:14 PM
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The shape of the filter makes it so that you can only replace it with an HKS product. On a happy note, you can put any cone filter on the HKS adapter as long as the ID for the filter is correct. A cone filter only costs about as much as the HKS replacement filter. You can try www.nopi.com for examples of cone filters.
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Old Jul 17, 2002 | 02:36 PM
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Would a K&N hi-flow filter be a better option than a Bonez/Apexi/HKS intake?
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Old Jul 17, 2002 | 02:39 PM
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Let's see, K&N is...
1.)Cheaper
2.)1,000,000 mile warranty
3.)Rechargeable/washable
4.)Flows better than 90% of the filers out there do

You decide
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Old Jul 17, 2002 | 03:38 PM
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If you're going to use a cone filter, you'll still need the HKS adapter. I think Jason sells them at www.rx7store.net for about $20.
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Old Jul 17, 2002 | 04:08 PM
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K&N does claim a dyno 5.5 HP and 5 ft/lb increase with their cone filter in a cool air box.
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Old Jul 17, 2002 | 04:30 PM
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Hmmm...so the HKS one is a POS? Damn! It's not that bad is it? Or is it serious enough to effect the longevity of my engine (the one thing I don't want to comprimise)?

So a K&N cone filter....they will go forever won't they?

Nima
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Old Jul 17, 2002 | 04:50 PM
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Whats the name/part no. for a K&N filter replacement kit for an 89 TII? I can´t find it.

Thanks!
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Old Jul 17, 2002 | 05:33 PM
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Re: Re: How much difference (HP) with a new air filter?

Originally posted by Scott 89t2


do you know how much boost you are running? do you have a FCD? a racing beat exhuast and an air filter will cause you to run too much boost. and make it unsafe unless you add more fuel.
Could anyone elaborate more on this. I'm thinking about getting a Bonez intake but might get a K&N filter for my stock airbox.
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Old Jul 17, 2002 | 08:36 PM
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Who's got a link for that air filter test web page?
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Old Jul 17, 2002 | 08:41 PM
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http://www.gtrowner.com/induction.html
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Old Jul 17, 2002 | 10:12 PM
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Originally posted by villeman
Whats the name/part no. for a K&N filter replacement kit for an 89 TII? I can´t find it.
Search and ye shall receive.
http://www.knfilters.com/appinq.htm

Originally posted by SerpentineGX
Could anyone elaborate more on this. I'm thinking about getting a Bonez intake but might get a K&N filter for my stock airbox.
The turbo will yield a higher output if the intake and exhaust restrictions are reduced. The wastegate can only handle so much flow, and if this flow rate is exceeded, then the boost will build up (kinda like how the water level will rise in a sink if the faucet outflows the drain). This is called "boost creep", and it can damage the engine. An intake alone will not cause boost creep, but if you add a high-flow exhaust you can expect trouble. The only way to stop boost creep is to increase the flow rate of the wastegate, which either means porting the stock wastegate (very small gain in flow rate), or installing an aftermarket wastegate (better gain in flow rate).

The fuel problem mentioned is in reference to the marginal stock TII fuel system. It can barely handle the stock boost level, so if more boost (ie more air) is present, then there simply isn't enough fuel to add to it. This means the engine will run lean, which will fry the engine in short order. The stock ECU has a fuel cut function which helps keep the driver from running the engine much past the stock boost limit. An FCD fools the ECU into thinking that it is running less boost than it actually is, which keeps the fuel flowing until the system just can't deliver any more.

The stock TII intake system is a bit restrictive for a modified engine, so most people use a cone-type filter instead of a drop-in type. If your car is close to the stock hp level, and you don't want to deal with the extra hassle of installing a cone filter, then the drop-in will be fine.

Originally posted by DCmina
http://www.gtrowner.com/induction.html
Hahaha, that is hilarious! Who needs SAE J726 standards when you have a vacuum cleaner and a handful of dirt? LOL, at least their hearts are in the right place, so I have to give them credit for that.

Last edited by Evil Aviator; Jul 17, 2002 at 10:23 PM.
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Old Jul 18, 2002 | 05:33 AM
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K&N does not make any intake kits for the 89TII.
They only make kits for 86-88.

What K&N kits are you guys using?


quote:
--------------------------------------------------------------------------------
Originally posted by villeman
Whats the name/part no. for a K&N filter replacement kit for an 89 TII? I can´t find it.
--------------------------------------------------------------------------------
quote:


Search and ye shall receive.
http://www.knfilters.com/appinq.htm
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Old Jul 18, 2002 | 02:41 PM
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Originally posted by Evil Aviator

An FCD fools the ECU into thinking that it is running less boost than it actually is, which keeps the fuel flowing until the system just can't deliver any more.
The exhaust i'm getting is the RB Complete system. I'll need the the "Fuel Cut Controller" for gas flow. Will that controller be sufficient enough to handle the proper fuel/air ratio? Or will I need to get a new wastgate? I'm looking for a slight increase of power (maybe more as time goes on) for now, but also want to keep a good balance with handling and speed.

Thanks for the info

Simon
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Old Jul 18, 2002 | 02:43 PM
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Originally posted by villeman
K&N does not make any intake kits for the 89TII.
They only make kits for 86-88.

What K&N kits are you guys using?
I was talking about the stock replacement filter.

PART #: RX-7 1.3L R2 F/I K&N Air Filter 33-2017 Turbo
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Old Jul 18, 2002 | 09:22 PM
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Originally posted by SerpentineGX


The exhaust i'm getting is the RB Complete system. I'll need the the "Fuel Cut Controller" for gas flow. Will that controller be sufficient enough to handle the proper fuel/air ratio? Or will I need to get a new wastgate? I'm looking for a slight increase of power (maybe more as time goes on) for now, but also want to keep a good balance with handling and speed.
You may be OK with the stock fuel system, but then again you may not. I guess you could install an aftermarket boost gauge and AFR meter and see whether the stock fuel system works or not. I would imagine that you will at least need a better fuel pump.

The Fuel Cut Controller (aka Fuel Cut Defenser or FCD) does not increase fuel flow. All it does is make the stock ECU think that it is running at a lower boost level so that it doesn't cut off the fuel when the factory max boost level is exceeded. If anything, this makes the engine run a bit lean because the ECU then uses fuel maps based on lower boost levels than are actually being produced. This isn't a big deal if you just add a little boost, but I wouldn't want to use an FCD at higher boost levels. An FCD is a band-aid; a fuel control computer or EMS is a cure.

The wastegate is an entirely different issue. The stock wastegate is fine unless boost creep becomes a problem.

This link may help you understand more about TII modifications:
http://fc3s-pro.com/TECH/tech.html
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