Itīs possible that my catalytic converter has to be replaced because of some damage in it. My question is if it would be better to get an OEM one or a high-flow one (exhaust system is and will stay stock!!!)??
Thanx in advance!

 

you may have cracked the ceramic element inside. If that collapses you could block the exhaust and have a serious meltdown.

 

why replace when you can upgrade?

 

You can get a high flow cat for $200. The cat from honda is going to run you about $600. I dont know about you, but i would get the high flow one for 200.

 

Get an aftermarket one. It's cheaper and you get less restriction from it.

 

If you dont have emmisions, then dont worry about having a cat. I recommend just having a straight pipe made. No restrictions what so ever.

 

Regardless (unless you NEED the performance for some crazy reason) keep it clean and just go with a high flow cat even if you don't have emissions laws. That's only if you care about what will happen in the next few decades. I'm not some crazy environmentalist, but for the extra 5 hp it frees it just isn't worth it IMHO.

~Doug

 

oh yes it is.

 

Haha, fine fine that's your call. Personally I don't like the idea of seeing blood moons everynight because of the smog.

But referring to the question stated above... If your exhaust system remains stock there's no reason to upgrade it, it won't yeild any power.


[Modified by TimeRacer, 6:05 PM 10/30/2002]

 

Emissions laws are very strict over here in germany but I wouldnīt want just a straight pipe anyways because of the reason you mentioned.

 

true. and i don't see a stock cat going bad in only two years anyway...
you sure this is the problem? maybe someone wants to rip you off...

 

Okay, here is the full story: I bought the car in january of this year from a Honda dealer (private car) who seemed to be about 60-65 years old and never drove the car fast. The car needed too much fuel for his taste so that he only revved it till 2.000 and most of the time even much lower. The result was that he killed the engine and replaced it with a new one before I bought it.
After driving it for a few month I drove on the highway (Autobahn) to see what topsspeed it has got. ONLY about 129mph!!!! But according to Honda topsspeed should be around 134mph. So I visited my local Honda dealer (not the one from who I bought the car) and the mechanic told me that there are two possibilities: 1.) the tach is a bit off
2.) cat is full of exhaust dirt because the car has never been "kicked" on the highway.
I donīt think that the mechanic would lie to me because I already know the garage since a few years and we are kind of friends. And thatīs why Iīm asking which way I should go.
I hope I havenīt made to many mistakes and that you got an idea about my problem! If not, SORRY!!!

 

If anything I can tell you that there is something wrong with the car minimally. I think most of us can contest that the 5th gen Prelude can easily attain 130 mph indicated. If you're mechanicly inclined (or you can ask your mechanic) to do a compression test first and then possibly remove the cat to see what it's condition is in. Though I find it strange that he would have to replace the engine because of the low RPM operation. I'm not sure what the dealer checked, but you should check if all the spark plugs are firing, each cylinder is getting fuel, good compression, remove the slack from the throttle cable, and a small list of other things... But it just boggles my mind the reason why the car would need a new engine..

I would be incredibly suprised if someone was actually able to drive this car below 2,000 rpm. Even flooring it you get less than 40 hp at that point in the power band.

 

If indeed your cat is seeing blockage they sell this stuff that will help you pass emissions tests. You put this stuff in your gas tank and run it like the directions say. It dislodges any stuff in your cat and hopefully restores some of the lost power.

 

The weird thing is that my acceleration seems to be fine because Iīve raced a lot of cars which should be a bit faster than mine and won against all of them (not in the 1/4 mile and only in acceleration, for example an old Porsche Boxster S, Audi TTs, a lot of BMWs, my fathers brand new Audi A4 quattro 3.0l,... ). I know that doesnīt mean that my car is faster than the ones I mentioned because itīll depend on the driver and a lot of other stuff but I just wanted to show that my acceleration seems to be fine. Maybe itīs really my tach???


On the other hand I donīt want a hella loud ride and pulleys and all this stuff are forbidden over here so a high-flow cat might be a good mod for me. What do you think? Would it be worth it with a stock exhaust system?

 

Not worth a penny with a stock exhaust system. However, you might as well pick up a Carsound cat (though you're going to have to get a exhaust company to weld the flanges on) since they're much cheaper than OEM IF that is the problem. Again, check other things first especially if it's a second engine. BTW at 2000 rpm you can't even go over 40 mph, I don't know how the old guy got around.

 

Maybe he has killed the engine in another way. Iīm not sure anymore. Possible that he never checked oil even if heīs a Honda dealer himself. He didnīt seem to have much knowledge about Hondas at all.