[cheesefries]

I have a FM2 with a high flow cat and FM duels. I just installed a complete 2 1/2 inch test pipe and it sound great.......but it feels slower. I actually notice it spools a little bit quicker but the butt dyno feels like its not as fast. Is my miata actually slower or maybe it made the whole powerband smoother so it feels slower? Any suggestions would be appreciated.

 

[Fritch]

yes, smoothing out the boost and torque curves will make the car feel different, only real way to tell is to dyno it.

 

[Max_Power]

Where did you get the test pipe?
I'm also thinking to get one, not sure if I should be from ebay or from boss frog...

 

[MiataRoadster]

Seen on one eBay ad:

"WE WERE INFORMED THAT IN THE NEAR FUTURE, THE SALE OF TEST PIPES ON EBAY MAY NO LONGER BE PERMITTED. IF YOU ARE THINKING ABOUT GETTING ONE FOR YOUR VEHICLE, GET ONE BEFORE IT'S TOO LATE!"

 

[Miatamoto]

Seen on one eBay ad:

"WE WERE INFORMED THAT IN THE NEAR FUTURE, THE SALE OF TEST PIPES ON EBAY MAY NO LONGER BE PERMITTED. IF YOU ARE THINKING ABOUT GETTING ONE FOR YOUR VEHICLE, GET ONE BEFORE IT'S TOO LATE!"

That guy has had that warning on his ads for a long time. That's where I bought my test pipe.

 

[roadsternut]

If it came about, sounds unenforceable, given the continuing legality of test pipes for road use in other countries.

 

[Max_Power]

I think I'll get one of these...
I was thinking if it's possible to cut the CAT into two and put it inside so that it looks like I have a CAT.

Do you know how much is the fine if they check under your car and see that you don't have a CAT?

 

[Ike]

If you are going through the trouble of putting a testpipe inside a cat, why not just clear out your cat. It's not hard to do, although my preference would be to by a high flow cat. They are cheap enough and effective. JMO

 

[Max_Power]

I know $90 or something...but would be more effective to have a test pipe?

 

[CrimsonMX5]

I think I'll get one of these...
I was thinking if it's possible to cut the CAT into two and put it inside so that it looks like I have a CAT.

Do you know how much is the fine if they check under your car and see that you don't have a CAT?

my friend with a supercharged rsx got caught with a test pipe..

I believe the fine was somewhere in the ballpark of $1300.00

 

[Matt [exz3owner]]

good looking car, Andrew. How did your friend get caught? I would think that a turbo miata is going to be busted for having a turbo and modified exhaust well before you are busted for a test pipe. My supra had a 4" cat that we welded into the downpipe. it didn't look like a cat at all. It looked like a 4" pipe. A cop isn't qualified to say what is OEM equipment, and what is not. All they can do is send you to a referee.

on another note - hollowing out a cat will create a resonating chamber in yor exhaust and in my experience, made the car significantly larger.

 

[kotomile]

^ what do you mean by significantly larger?

 

[Matt [exz3owner]]

it added a backseat.

Kidding. I miss typed. Louder. not larger.

 

[CrimsonMX5]

@ Fri Sep 01, 2006 6:46 am]good looking car, Andrew. How did your friend get caught? I would think that a turbo miata is going to be busted for having a turbo and modified exhaust well before you are busted for a test pipe. My supra had a 4" cat that we welded into the downpipe. it didn't look like a cat at all. It looked like a 4" pipe. A cop isn't qualified to say what is OEM equipment, and what is not. All they can do is send you to a referee.

on another note - hollowing out a cat will create a resonating chamber in yor exhaust and in my experience, made the car significantly larger.

Thanks,

my friend said they pulled him over because he had a loud exhaust.. they further inspected his car and saw that he had a JR s/c..

then he said they sent over one of those special task forces.. they came over inspected my friend's car, and told him to turn it on rev it a couple times etc..

he said that is too loud and looked under the car with a mirror and saw no cat..

 

[Max_Power]

@ Fri Sep 01, 2006 6:46 am]good looking car, Andrew. How did your friend get caught? I would think that a turbo miata is going to be busted for having a turbo and modified exhaust well before you are busted for a test pipe. My supra had a 4" cat that we welded into the downpipe. it didn't look like a cat at all. It looked like a 4" pipe. A cop isn't qualified to say what is OEM equipment, and what is not. All they can do is send you to a referee.

on another note - hollowing out a cat will create a resonating chamber in yor exhaust and in my experience, made the car significantly larger.

Thanks,

my friend said they pulled him over because he had a loud exhaust.. they further inspected his car and saw that he had a JR s/c..

then he said they sent over one of those special task forces.. they came over inspected my friend's car, and told him to turn it on rev it a couple times etc..

he said that is too loud and looked under the car with a mirror and saw no cat..

That's good information Andrew
Thanks for sharing it
It seems that it's better to drill the cat than to put a test pipe...or to put a racing cat and not worry about anything...
I think that's the way to go...
a friend of mine fwd me a link with high flow cats that were only $90 or something (btw not generic for miata)...

 

[Gumby]

http://www.miatamania.com/Shop/ViewProducts.aspx?PlateIndexID=51154

Works great might wanna change out the gaskets though the ones that come /w it are'nt the greatest

 

[roadsternut]

A hollowed out cat will also make the car run rough; best banging some 2" steel or copper pipe through it.

BTW, Copper piping makes for a great sounding exhaust. Big Triumph owners have been using this for years.

 

[AMMendes]

Max_Power, since you are from EU you have Ilmotorsport.com and the MX5Parts.co.uk, they both have some test pipes and i think free flow kats, but not sure.

 

[Max_Power]

Max_Power, since you are from EU you have Ilmotorsport.com and the MX5Parts.co.uk, they both have some test pipes and i think free flow kats, but not sure.

Thank you AMMendes, I shopped many times from IL Motorsport and they are awesome.
Btw even though I'm Greek I'm living in California for the last five years...

 

[30hourpunch]

I don't recommend hollowing out the oem cat, I did and I didn't see any hp gains via the good ole butt dyno.The exhaust note however had some sort of weird hollow pinging type noise. really hard to describe. I ran a test pipe amd liked the results.