ditching the cat on my del sol

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i am thinking about getting rid of the cat on my 94 del sol and running a straight pipe to the exhaust. any suggestions on how to do it? and what kind of exhaust i should buy?
 
Dude, you have a completely stock D16 Del Sol! The gains would NOT be worth it! Let me put it this way.

DONT DO IT.

A) Its a federal offense to remove/modify a working catalytic converter.
B) It will further improve the "ass" quality of sound emanating from your vehicle.
C) Unless the cat is severely clogged this will do NOTHING in terms of performance, and if that's the case, replace it with a high flow version (since they cost less then OEM units)
D) Its rather bad for the environment. You don't HATE the environment, do you?
 
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i am thinking about getting rid of the cat on my 94 del sol and running a straight pipe to the exhaust. any suggestions on how to do it? and what kind of exhaust i should buy?
get rid of it get a flex pipe and run a straight pipe with a greddy muffler.
 
i hate u douche bag!
you never freaking help me!
all you do is give stupid irrelevant suggestions.
your not that smart!

Oh, I'm sorry. I thought you wanted me to tell the truth.

Let me change what I previously said to what you want to hear instead...

"By all means, gut your cat or run a test pipe on your 17 second rocket, so your highly increased nOX, Benzene, and various other unburned carcinogenic particulate emissions can be spewed into the atmosphere! I mean, the slight loss of low end torque, 0.0001WHP gain elsewhere in the RPM band, and increase in annoying ricer-esque rapines exhaust noise is well worth the time and effort! Not to mention the huge fine which could be imposed upon you if caught by the authorities.

You = smart!"

Edit: If you would get your head out of your 15 year old ass you might be able to see that I am trying to help you.

your not that smart!
Oh zeh ironiez!

I’ll just leave now so you and Darwin can finish playing.
 
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why dont you go back to hell where you came from you asshole!
i asked a simple question and you have to think your so smart!
i think you the one with his head up his ass!
 
i am thinking about getting rid of the cat on my 94 del sol and running a straight pipe to the exhaust. any suggestions on how to do it? and what kind of exhaust i should buy?


If your a hands on guy and have the time and means to do it, make your own pipe.
But I'm sure you can find one on ebay or something, if your not looking to spend to much money.

But invidia IMO makes the best exhaust systems, but rather pricy, another great company to look into is Greddy, little less expensive.

Let me know if you need help finding one.
 
why dont you go back to hell where you came from you asshole!
i asked a simple question and you have to think your so smart!
i think you the one with his head up his ass!

You asked a simple question, and he gave you a very simple and accurate answer. Provided you had done any research on your own instead of asking people for all of the answers, you would have known the pros and cons of each.

There is no education like self education.

You, sir, need to get off your high-horse. Or your stay here could be short and miserable.
 
I've had straight pipes on my Civic and CRX. Yes, I did notice a gain too; compared to the stock Std exhaust(which also had no cat since it was built onto the header). Although, main reason I had a straight pipe were; my first CRX came like that, and I replaced the header on my Civic with a 4-1 header; and didn't have money for a cat at the time. My main complaint about running cat-less is, it stinks(smells like a lawnmower you could say). Noise can easily be baffled down with a good resonator and muffler; but only a catalytic converter will get rid of that smell.

Best way is to have a custom exhaust setup. Just get the muffler/resonator you want to run, and have them set it up. Although, it is illegal, you can have a cat and just swap it out with a test pipe if you like.

BTW, in my 88 Civic with a cam'd D15B and (Accord intake)/H/E, with a short transmission, I managed 57MPG while cruising at 65-70mph most of the time(around 3700-4000rpm)....with an open header. :D
 
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if the rest of your exhaust is opened up (you have a header and cat back exhaust) then a test pipe will definitely make good hp gains. if its the only mod you have done to your exhaust then i would imagine the gain would only be very slight.

yes, the exhaust does stink with no cat, and yes it will make it louder. you will need a resonator and a good muffler to keep it from soundy raspy.
 
You asked a simple question, and he gave you a very simple and accurate answer. Provided you had done any research on your own instead of asking people for all of the answers, you would have known the pros and cons of each.

There is no education like self education.

You, sir, need to get off your high-horse. Or your stay here could be short and miserable.

Thank you.

Now speaking of RESEARCH, lets see if this 15 year old know-it-all can manage to get past all the big words in this article and learn a little more about what he thinks is a good idea:

Catalytic Converter Removal - Beat the Law - Import Tuner Magazine

Hell bent on wrangling every last horsepower out of their steeds, power mongers often run sans-converter on the street; risking tickets, huge fines or even impoundment of their vehicles. But just how much power are they gaining, and is it really worth the risk? If the thought of surrendering your car to the local towing yard keeps you from yanking your converter, there still may be a way to make more power and not break the law.


With the testing of all three cats out of the way, it was time to unplug the exhaust and let her rip without that pesky brick in the exhaust. No matter how you cut it, a cat is a restriction and costs power, right? With the moment of truth at hand, we bolted in our test pipe - eliminating the cat entirely. On our final pull we stood eagerly by the dyno's monitor, waiting to see the results. Wait ... here it comes ... 152hp and 108 lb-ft - a gain of one measly horsepower and one lb-ft of torque at the cost of breaking the law.

Now, keep in mind that this test was done with a 1999 EM1 Civic Si with quality intake, header and cat-back exhaust. Point being that this car not only makes a shit-ton more HP then your Del Slow in stock form, but it's B16A2 engine responds more to breathing mods. Bottom line being, that any and all gains here are going to be LESS in your application.

But let’s play in fantasy land. Say you get a whopping 5WHP out of adding a test pipe without the aid of things like... ohhh... 35 extra stock BHP, one of the best flowing heads out of any B series motor, a MUCH higher engine VE, plus a myriad of other factors not the least of which being the addition of a high quality intake header and cat-back exhaust.

That would mean you are making an ass-ripping, hernia inducing, asphalt eating 110FWHP vs. the stock ~105!!!!

YEA! That’s well worth increasing your hydrocarbon emissions by 75-90% alone! Not to mention the average 2500 to 5000 dollar fine for modifying/removing a working automotive emissions component, possible impoundment of your vehicle, making everyone sitting behind you in traffic smell your ass fumes, and helping your car sound even more rice like.

You say I "don’t help you"? I say get your head out of the sand and see reality for what it is.

I already told you in your other thread that throwing BPU bolt-ons on your D16 Del Sol isn’t going to make it "fast". It will still be a slow, 16 (if you are lucky MAYBE high 15) second, FWD econobox. Thus, you should spend your time/money on purchasing some nice OEM 15-16" rims, sticky tires, quality suspension components, brakes upgrades, and most of all DRIVING LESSONS.

But what do I know? I've only been doing this stuff since you were LITERALLY wearing diapers.
 
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Same here, but I was out of diapers when Mister^2 was born. :D

I personally dyno'd my built Civic with 3 different setups:
- stock catalytic coverter
- Random Technologies 2.5" high flow cat
- 2.5" straight resonated pipe that looks exactly like a real cat on the outside
Everything else was identical.

All 3 setups dyno'd within 1hp of each other (184-185whp). The sound was different, the stench was different- but in the end, I kept the high flow catalytic converter on instead of the straight pipe. The extra raspiness and stink wasn't worth it to me, and my bumper stayed a little less black. You super old-school members will remember my black bumper on the white car.

As it stands, I do use the straight pipe on one of my Hondas, but not because I wanted a power boost- only because it was the fastest and cheapest way to get the stock exhaust manifold to couple to a new custom 2.5" exhaust system and still be able to change out components later- like adding a real 2.5" high flow cat. I won't tell you which Honda.

If you have to pay money for anything, just get a new high flow cat. It's the best deal, it won't get you in trouble for a $10k+ fine, and the back end of your car won't stink.
 
What I did on my brother's GT-30R powered WRX was to use a 4" Random Tech high flow cat. He is running 3" exhaust pipe (3" DP and 3" turbo-back), so all we had to do was couple the larger diameter catalytic converter, which was very easy. We did this to maximize air flow, while creating pretty much ZERO bottleneck @ the cat.

I learned this little trick while working on my friend's 10 second FD RX7. A car, BTW, which is EXEMPT from any and all smog laws given the fact that it's trailored to the track and back (read: not a street car). Even still, he put the cats (yes, plural cats; he swapped a bored out 6.0l Chevy LS1 into it) on his car as not to further help completely destroy the ozone layer. However, even if you don't care about pollution, it still does wonders if you want to keep your car from failing the sniffer test and/or visual inspection when you have to smog it and/or get pulled over by a zealous traffic cop.

BTW, that FD is not just a drag strip king. He plays with it at road course and auto-x events and WINS.

That being said, I remember when Road & Track did a test on the Random tech cats soon after their initial release. They did a test on a Dodge Viper RT/10 (this was before the days of the GTS). The Random Tech free flow cat actually made more torque (same HP) as a full on 3.5" test pipe bolted up to the stock exhaust system.
 
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Good thing I live in NC and not CA. 95 and older are exempt from smog testing. :D

Also, I guess sort of described above(about the larger cat); possible gains will also depend on what you're replacing. You'll see a gain if cat is clogged are there's some other bottleneck in the exhaust system; but usually the only gain is noise and stink.
 
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