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Guest Message by DevFuse
 

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Intake & exhaust mods....


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17 replies to this topic

#1 Guest_Toyofast_*

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Posted 10 August 2003 - 09:30 PM

So on my '90 1.8 FI'ed engine....
What's the best way to increase air entering the engine?
Cut holes in air box, Cold air intake setup, change air filter only... Which way is best? Other options?

For exhaust, how big of exhaust pipe diameter can I go? Which size is best? Muffler choice? I want something that will sound good, not a fart can sound but more of a very low rumble/quiet sound.

#2 Guest_bushbasher_*

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Posted 10 August 2003 - 10:18 PM

People on the board have used 1-7/8 to 2 1/2" with good results. Pretty much any performance muffler is gonna give you a big improvement, the stock ones are sheeit. Hopefully some will chime in with what they are using. Also, if you don't have to worry about emissions, you might want to remove the catilytic? converter. For intakes, cutting the bottom of the airbox out works great. I myself have never been able to notice the difference with a cold air intake, though this is on other cars, not subies.

#3 Guest_Flowmastered87GL_*

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Posted 10 August 2003 - 10:25 PM

Probably an intake would work the best. Build a little wall to keep engine heat away from it too and try to remove the intake silencer stuff from inside the fender so more air can get to the filter area of the engine bay.

I run 2.0 piping to a Y cat (2 in 1 out) then 2.25 to a Flowmaster 40 series delta flow then 2.5 out. The full exhaust system cost somewhere in the area of $425 including installation. Price can vary somewhat depending on what the shop has to start with. I supplied the muffler for mine, but they had to modify it to fit the pipe size I wanted.

I went to exhaust specialties on 7th and belmont. They are the best in my town in my opinion (Rallitek.com uses them)

#4 Guest_electryc monk_*

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Posted 10 August 2003 - 11:03 PM

currently I am running a 2.5" from the turbo all the way back with a 3-way cat and turbo muffler. Quiet enough to have calm convo's at freeway speeds and not realize its that loud. But admitedly a turbo does a bang-up job on any exhaust noise's.

as for intake...welll i snorkel-ectomied and will be making a modified(somehow) intake over the next few days...... something for sure with the new "lifting having been acomplished.

#5 Guest_Toyofast_*

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Posted 10 August 2003 - 11:21 PM

<blockquote><strong><em>Quote:</em></strong><hr>I run 2.0 piping to a Y cat (2 in 1 out) then 2.25 to a Flowmaster 40 series delta flow then 2.5 out. The full exhaust system cost somewhere in the area of $425 including installation. Price can vary somewhat depending on what the shop has to start with. I supplied the muffler for mine, but they had to modify it to fit the pipe size I wanted.[/quote]

I feel confident enough with my fab skillz that I'd rather build up my own, rather than pay someone else.... unless I have the extra cash and/or need something special done.

I'm not sure if I'll be registering this car here in the DEQ area or outside of it at my parents home in Central Oregon... That's where my Toyota is currently registered, out of DEQ range:smokin:

I figured the first mod would be changing something about the intake to get more air into the engine. Just need to get more ideas on what exactly to do though....

Anyone got good write-ups and/or images of your setup??

#6 Guest_calebz_*

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Posted 10 August 2003 - 11:27 PM

You can go with the cold air intake setup, or a cheaper, possibly easier method would be to cut out the bottom of the airbox. Mine was done in a very professional manner(Thanks Rob).. Looks completely stock, but on the underside of the box, there's only enough metal to clamp it down.. all the rest is gone.. leaving an air intake are of about 6 inches by 8 inches open to the breeze.

#7 Guest_samo_*

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Posted 11 August 2003 - 12:09 AM

If you take a look at my cardomain site, you can see the intake setup I put on my SPFI Loyale. The MAF adaptor is off a Nissan GA16DE intake (I used to have a Sentra) and the filter is a Weapon-R Dragon filter. I would avoid foam or metal element filters on cars that go off-road, though. Stick with a cotton element if it'll be spending lots of time in the dirt.

#8 Guest_Toyofast_*

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Posted 11 August 2003 - 12:12 AM

<blockquote><strong><em>Quote:</em></strong><hr>If you take a look at my cardomain site[/quote]

Which is ??

#9 Guest_uhohru_*

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Posted 11 August 2003 - 12:16 AM

I'll be running the stock 1.75" off the block to Y pipe that goes to 2.5"....

2.5" will meet up with a glasspack in the engine bay and continue to run through the hood to a 4" turndown tip.

No cats, No mufflers..

#10 Guest_jon61484_*

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Posted 11 August 2003 - 12:56 AM

I've got a carbed EA81. What about this?

no cats, dual, h pipe, 1.75" all the way, 2x(2" RAPTOR mufflers)

good?

#11 Guest_Flowmastered87GL_*

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Posted 11 August 2003 - 02:17 AM

Toyo, if you want to hear my car let me know. I will be out near the U-Pull-It on Foster road tomorrow getting parts for my new project car.

The flowmaster makes it sound mean :evil:

#12 Guest_uhohru_*

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Posted 11 August 2003 - 03:12 PM

I have flowmaster on my 2000 Impreza 2.5 RS

It sounds much better there than on an L or an M.Y.

#13 Guest_samo_*

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Posted 11 August 2003 - 09:18 PM

Toyofast - I have no idea why it didn't add my signature, which has the link to my site. Nonetheless, it's www.cardomain.com/id/samo_ownz_yuo :) .

#14 Guest_Toyofast_*

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Posted 11 August 2003 - 09:55 PM

<blockquote><strong><em>Quote:</em></strong><hr>Toyo, if you want to hear my car let me know. I will be out near the U-Pull-It on Foster road tomorrow getting parts for my new project car.[/quote]

Sorry... got to many "honey-do's" for most of the week. But I was thinking about asking you if I could here your car rumble, guess you offered quicker than I asked!

BUT yeah...I would like to hear/check out your car sometime, just not sure when I'll have free time. I'll be sure to find out and then get back to you.

#15 Guest_Newsance_*

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Posted 11 August 2003 - 10:04 PM

Oh come on people. Is it really worth the 2 HP gain to rip out your cat, and turn a clean running vehicle into a gross polluter? A catalytic converter is the single most effective emissions device on a vehicle, and a properly selected cat WILL NOT COST MEANINGFUL POWER. None of you are building full race cars, so why? Why tear your cat off on a car that spend 95% of it's time driving you to the grocery store?

If you really want to build an effective exhaust system, look up summit racing's prices on CATCO cats. For 40 bucks, you can get a cat that will work effectively, and flow more air than you could ever get through the sub 2 liter puttwagon motors in these cars.

If the environmental aspect doesn't appeal to you, consider that being caught on public roadways without functional emissions equipment can be a $1000 fine, and I have been given a roadside inspection before.

For what it's worth, my 11 second Firebird Formula has a 3" catco on it that cost 30 something on sale. A ton of magazines have done dyno tests showing that a properly sized cat costs less than 5 hp on most anything mild enough to still be considered a street car.

If you want to spend good money getting a larger exhaust made and drill out holes in your airbox, heck, it's your money. Personally, I don't see that there are parts availible to make any real performance difference in these old clunkers, (no decent cams, heads, etc, at least not for a realistic price/performance ratio) so I am perfectly fine with accepting the 80-odd hp. If I ever need more than that, then I need to look at motor swaps. Anyways, what you do to your vehicle is up to you, but hacking up the emissions stuff is meaningless and harms everyone.

#16 Guest_calebz_*

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Posted 11 August 2003 - 10:30 PM

<blockquote><strong><em>Quote:</em></strong><hr>If you want to spend good money getting a larger exhaust made and drill out holes in your airbox, heck, it's your money[/quote]

If you really do posess an 11 second firebird, then you should know that Air going in and Air going out are very important aspects of performance. If you spend a little time looking around the forum, you will also find that there are those out there that have managed to get a legal EA82 up into the 150-160hp range. its not unheard of. You can keep your 80hp and if it suits you, thats great. I happen to like the 115 from my 87 TurboWagon. And I will like it even more as the HP goes up. There are many ways to increase HP without failing emissions inspections. Having a turbo car to begin with is a good start. Increased airflow is also good. Increase in boost is also a good thing. If done properly, neither of these things should affect emissions.

You say there are no cams and heads available. As straight bolt on, you are correct. However anyone with the right knowledge can have a machine shop grind cams, port/polish heads and other such things.

There's also C/R. EA71 pistons into an EA81 motor will raise C/R, thus giving more power. EA82 SPFI pistons into an EA82T mpfi block will do the same.

Its ok to sell yourself short, but try not to sell others short in the process

#17 Guest_Toyofast_*

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Posted 11 August 2003 - 11:12 PM

<blockquote><strong><em>Quote:</em></strong><hr>If the environmental aspect doesn't appeal to you, consider that being caught on public roadways without functional emissions equipment can be a $1000 fine, and I have been given a roadside inspection before.[/quote]

I never said anything about removing the cat... I would like to keep the car smog legal even <em>if</em> I decide to register it out of DEQ range/area. Plus I know that removing the cat doesn't do much, maybe 1-2 hp if that... no need to really remove it, just punch out the guts:p

<blockquote><strong><em>Quote:</em></strong><hr>If you want to spend good money getting a larger exhaust made and drill out holes in your airbox, heck, it's your money.[/quote]

Drilling out air box... free.
Larger exhaust, I only asked what size everyone was running to get an idea of what seems to work for people....Plus I feel good enough about my fab skillz that I would try to build my own rather than pay a shop to make the same. BUT if I were to pay a shop to do my exhaust I'd probably want to travel down to Southern Oregon to get it done at <a href="http://www.mikesmuffleradvantage.com/" target="top">Mike's Mufflers</a>. This is where I had my stuff done for my Toyota and everything is custom bent(no pre-bent stuff), top notch work. Prices are sweet too.

#18 Guest_uhohru_*

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Posted 12 August 2003 - 08:56 AM

No I believe I was the one who said something about completely getting rid of the two cats.

Newsance--

1. You said you get 2 hp a cat correct?
2+2=4hp
I'll take it.

2. My car is 100% offroad, used maybe 1-2 times/month. It DOES NOT SPEND 95% OF ITS LIFE GOING TO THE STORE. NUH UH!

3. And as far as 1000$ fine...
It doesn't concern me, My car is registered in WASILLA, AK and in that part of Alaska, emissions is NOT REQUIRED! All I have to do, is register my car, and I receive tags. I will not be able to travel to Anchorage, (Ask SubaruJunkie on this), but my car will be stationed in Wasilla, and will travel the outer boundaries of Willow, Biglake, Sutton, etc etc etc...

Period dot, no emissions for my car...

4. As far as airbox mods, I'll soon be running nitrous oxide into my motor... not so environmentally friendly? I also run an XT6 MAF which i believe makes my car run lean for some reason, but causes the computer to think its not sucking in enough air, idle changes to approx 1100 RPM's on EA82. The computer was reset to accept this change. The airbox has been sealed, and the fender (cold air duct) has been removed.

So if I can rip my exhaust off for 4 HP and better NOS effect..

Im going to do so. :evil:




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