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2 1/2 inch exhaust on non turbo mx5?

Posted: Mon Feb 16, 2009 1:36 pm
by crzymx
Guys i found an aftermarket exhaust system on ebay which is second hand. Guy claims it will fit 89-97 however i can imagine that it wouild fit a 00 with some minor modifications done by my exhaust place. Now the system is s 1/2 inch and i was wondering if this would reduce performance on a non turbo mx5 as this size is common on most 'turbo' mx5's.

Thanks.

2 1/2 inch exhaust on non turbo mx5?

Posted: Mon Feb 16, 2009 2:31 pm
by AB7
2 1/4 is the best for non turbo MX5.
I know some people here run 2.5" system, but IMO its a tad too big.

BTW Im selling my 2 1/4" stainless steel mid pipe pipe with hi-flow cat & resonator soon.
You can have a look at it if you want, Im in Melbourne too.

2 1/2 inch exhaust on non turbo mx5?

Posted: Mon Feb 16, 2009 4:50 pm
by pcmx5
you may be better looking at the NA system as the 00 would require a bit of work,plus I agree it is too big. Wait till the dyno day and see how the various exhausts perform!!

peter.

2 1/2 inch exhaust on non turbo mx5?

Posted: Mon Feb 16, 2009 9:21 pm
by Tedsmx5
I have a 2 1/2" system (and ceramic coated headers) fitted to my na8 mx5, had a dyno done before and after, a net 10% increase in HP across the rpm range. The tail pipe is 2 1/4" as it keeps the noise down (the exhaust gas has cooled and slowed down by the time it's reached the tail pipe), the car is now supercharged with the same system.
Ted

2 1/2 inch exhaust on non turbo mx5?

Posted: Mon Feb 16, 2009 9:22 pm
by manga_blue
NA and NB pipework are very different. You end up totally butchering it when you change either way. It's way simpler to start with the right one in the first place.

2 1/2 inch exhaust on non turbo mx5?

Posted: Mon Feb 16, 2009 10:55 pm
by crzymx
Does it matter though since they are both aftermarket. Just means hooks are different? Im most likely going for ab7's setup.

2 1/2 inch exhaust on non turbo mx5?

Posted: Mon Feb 16, 2009 11:16 pm
by crzymx
pcmx5 wrote:you may be better looking at the NA system as the 00 would require a bit of work,plus I agree it is too big. Wait till the dyno day and see how the various exhausts perform!!

peter.


I have a 00 nb, but the system is na. Do you think i should try and get it installed before the day if possible ?

2 1/2 inch exhaust on non turbo mx5?

Posted: Mon Feb 16, 2009 11:16 pm
by sliq
crzymx wrote:Does it matter though since they are both aftermarket. Just means hooks are different? Im most likely going for ab7's setup.


yes, it does matter.

if i were u, i'd do thorough research before deciding on exactly what exhaust you want having regard to whether you want a full exhaust from header to muffler, cat back, whether you want mild steel or stainless, and what tone you are after.

2 1/2 inch exhaust on non turbo mx5?

Posted: Mon Feb 16, 2009 11:39 pm
by crzymx
Well ive done my research (im pretty car literate ;)). I want a header back system, midpipe, hi flow cat, resonator, and i already have a performance muffler. Mild steel would be preferable, but stainless wont kill me. I know stainless is a little bit more raspy but its no major drama. Headers are not a big factor atm, and the tone doesnt bother me as i have an idea of what im gonna get out of the 2 1/4. Im hoping its going to have a nice deep hop when the car is idle, but just subtle, and then agressive with throttle play. Im just trying to suss out a system i want, i think i might give the ebay one a flick, im pretty keen on ab7's setup./

2 1/2 inch exhaust on non turbo mx5?

Posted: Mon Feb 16, 2009 11:56 pm
by wun911
any chance your selling those fine extractors as well???

2 1/2 inch exhaust on non turbo mx5?

Posted: Tue Feb 17, 2009 1:42 am
by CheyneX5
crzymx wrote:Well ive done my research (im pretty car literate ;)). I want a header back system, midpipe, hi flow cat, resonator, and i already have a performance muffler. Mild steel would be preferable, but stainless wont kill me. I know stainless is a little bit more raspy but its no major drama. Headers are not a big factor atm, and the tone doesnt bother me as i have an idea of what im gonna get out of the 2 1/4. Im hoping its going to have a nice deep hop when the car is idle, but just subtle, and then agressive with throttle play. Im just trying to suss out a system i want, i think i might give the ebay one a flick, im pretty keen on ab7's setup./


Don't you think you should check your motor is in good working order first? You always seem quite hesitant that somehthing is going to wrong with it :?

2 1/2 inch exhaust on non turbo mx5?

Posted: Tue Feb 17, 2009 8:20 am
by pcmx5
crzymx wrote:Well ive done my research (im pretty car literate ;)). I want a header back system, midpipe, hi flow cat, resonator, and i already have a performance muffler. Mild steel would be preferable, but stainless wont kill me. I know stainless is a little bit more raspy but its no major drama. Headers are not a big factor atm, and the tone doesnt bother me as i have an idea of what im gonna get out of the 2 1/4. Im hoping its going to have a nice deep hop when the car is idle, but just subtle, and then agressive with throttle play. Im just trying to suss out a system i want, i think i might give the ebay one a flick, im pretty keen on ab7's setup./


At the Dyno day you will get a few examples of what difference the Town and Country catback makes on a range of cars, plus a few other systems.

I would wait till then, you will get a base figure, and could always spend another $50 later to go back on the dyno at another time and see what gains you have made from what you do to the exhaust

LeonW got about 8RWKW from headers and the exhaust on his NB8A and I think the NB headers are good stock so probably picked up about 6RWKW from the exhaust.

Chris h's NB8C has a T&C set up and he will be there;previously made 72RWKW stock so that will also give you a guide.

Peter.

2 1/2 inch exhaust on non turbo mx5?

Posted: Tue Feb 17, 2009 9:09 am
by daffyflyer
Well I have a 2.5" and it perked the motor up a lot, big difference (along with intake and timing), dunno if smaller would be better but....


Not too loud either, i thought it was it first, but now im used to it, it just sounds fast :D

2 1/2 inch exhaust on non turbo mx5?

Posted: Tue Feb 17, 2009 9:46 am
by AB7
wun911 wrote:any chance your selling those fine extractors as well???


I assumed you are asking me?
No, Im not selling my extractor, the reason Im selling my midpipe is I have another one in my garage which I was going to use for racing only ( straight through pipe )...but after long after deliberating, Im going to use it plus a high flow cat and no resonator this time( Yes, Sliq...Im going to do it :) ). It makes more sense rather than chopping my resonator off my current one.

2 1/2 inch exhaust on non turbo mx5?

Posted: Tue Feb 17, 2009 9:46 am
by AB7
Double post