I just installed a test pipe on my 5th gen. Since the test pipe doesn't use the after the cat. o2 sensor, can this hurt the engine in anyway except for running leaner???

 

Gas mileage will begin to suck bad and mine went into safe mode after a little while, but you can reset it and it'll be fine for a couple of weeks. I don't think i'd be able to drive again with out the second O2 sensor my car just ran like crap and I got terrible mileage. Then again I wasn't tuned or anything with it.

 

Get rid of OBD2 lol

 

I installed my test pipe about a year ago, and picked up almost 2mpg. The car was also noticeably quicker.

I just left the secondary O2 sensor in the exhaust. The CEL is on, but the car doesn't go into any limp or backup mode. Everything works fine.

Best $35 I spent on ebay yet!

 

move the secondary o2 farther down the exhaust so it can detect the temp diff it needs to see.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MC_HondaRacing &raquo;</TD></TR><TR><TD CLASS="quote">I installed my test pipe about a year ago, and picked up almost 2mpg. The car was also noticeably quicker.
</TD></TR></TABLE>

2 mpg more daily driven? Weird. Cats are better for low end power, the test pipe just opens up top end more.

 

How much louder does your car run with the test pipe instead of a high flow cat?

 

Enough louder to make the difference between people hearing me while i'm on my cell phone and people not being able to hear me. Of course this really depends on the rest of your exhaust, but sound quality of your exhaust is a lot worse (raspy). When I switched from test pipe (had one for a year) to hi-flow cat, I felt midrange power pick up, and I really can't notice much differnce on top end. IMO, test pipes just aren't worth it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Drag’nGT &raquo;</TD></TR><TR><TD CLASS="quote">How much louder does your car run with the test pipe instead of a high flow cat?</TD></TR></TABLE>

Its not that it is louder per say, it just has a different tone to it. A test pipe sounds very raspy, whereas a high flow cat filters out some of the raspyness.

 

run an O2 sim...

 

2 mpg more daily driven? Weird. Cats are better for low end power, the test pipe just opens up top end more.[/QUOTE]

I don't think cats really do much for power, other than potentially limit it. Do you have some information on this??? My car picked up power everywhere, but one thing I'm doing differently than many of you is that I still have my OEM cat-back exhaust. The test pipe was really just a temporary thing for me until I get a high flow cat and custom cat-back finished. The sound isn't any different than it was with the cat. So.... in the end I picked up power, fuel economy, and I don't get harrassed by the cops because all they see from the back is an unmodified Honda exhaust.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MC_HondaRacing &raquo;</TD></TR><TR><TD CLASS="quote">I don't think cats really do much for power, other than potentially limit it. Do you have some information on this??? </TD></TR></TABLE>

Added backpressure, in theory, helps mid-range but hurts top end. In my experience, all I have for comparison is 1/4 et's for top end comparison. With my test pipe on, I ran 13.8 @99. Since then I have swapped out for GSR brakes all around (more weight), installed a catch can (no effect on performance), relocated my battery (less weight on front tires to get traction), and installed a magnaflow hi-flow cat. Just last night I ran a 13.9 @ 98. My 60' time was .05 off what it was when I ran the 13.8 (which could account for the entire .1 diff in et). So for me, swapping the test pipe for a cat didn't seem to hurt acceleration.

 

for good ****

 

like above said run an o2 sim to get rid of that check light

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by MC_HondaRacing &raquo;</TD></TR><TR><TD CLASS="quote">I installed my test pipe about a year ago, and picked up almost 2mpg. The car was also noticeably quicker.

I just left the secondary O2 sensor in the exhaust. The CEL is on, but the car doesn't go into any limp or backup mode. Everything works fine.

Best $35 I spent on ebay yet!</TD></TR></TABLE>

spend another $15 and get an o2 sim....<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Drag’nGT &raquo;</TD></TR><TR><TD CLASS="quote">How much louder does your car run with the test pipe instead of a high flow cat?</TD></TR></TABLE>

probably not any louder, just raspier, with a side of flames at times....

 

I noticed a pick up in gas mileage, too. Make sure you tune because before I tuned with the test pipe, the ecu kept throwing a air/fuel code...I forget which one it is.

 

I think the point is made that a good high flow cat is probably no, or minimal, deficite on the Prelude compared to a test pipe. However, if anyone is really gaining power from backpressure reduction, then you would be better served by leaving the low backpressure exhaust on and re-evaluating the exhaust cam timing. If you go with a minimum backpressure exhaust, try advancing the exhaust cam, and see if you don't get the best performance from that.

 

were boys i found this one for my car it's cheaper than a simulator and for 2 weeks since i've installed it hasn't flipped the cel.
http://forums.evolutionm.net/s...14931

 

pretty cool work around.

 

sorry for changin the subject but...can anybody help me out with a high-flo cat...from ur experience what is a good company that makes them?

 

Magnaflow/CarSound, Random Technology, Catco Catalytic Converters

 

i like that fix....good thinking....but with a soldiering iron and an hour, the $15 sim from thebestmileliminators (seller on ebay) will work perfect....

 

if i'm reviving this, my bad, but Pacesetter makes a high-flow cat that i'm thinking of getting, but my catback is a 2" pipe and the cat smaller....am i going loose power, or would it be the same principle as a reversed funnel, after the cat it gets wider?

 

If the cat is smaller than your exhaust, you're hurting yourself.

 

its the same width as the header though....it'll all run through then open up after the cat.

 

Hahaha......1-2whp is Strong!