VIC - NB8a Cat Back Exhaust

[Gazbag]

Hey guys,

Looking to get a cat back exhaust for my NB8a. I'm located in the Western Suburbs of Melbourne.

Car is used on track but remains road registered so I'm not looking for anything too aggressive. I've read some good reviews for Town & Country in Geelong but the reviews are 4-5 years old. Do these guys still do a good job or does anyone have any other recommendations?

Many thanks in advance!

G

[pcmx5]

You may get more feedback in the engine section.T&C have done over 120 Mx5's and as far as I know no issues and some very positive feedback.

Peter.

[Ned Loh]

Racing beat are quality, but expensive.

[pcmx5]

You should also factor in that the Cat will probably be stuffed if it hasn't been changed so you may really be looking for a complete system but thankfully the standard headers are pretty good.Some T&C systems have given up to 10 or so RWKW improvement when the cat has been stuffed,same day tested on the same dyno.

Peter.

As most people on the forum will know I am a friend of Colin at T&C and have helped with testing the systems but have no financial interest .

[CrazyRacer]

Another vote here for T&C.

Had one of their systems that includes a new cat fitted to my NB8A.

Not as pretty as some of the full stainless systems, but by my "seat of the pants dyno" I would say you get a small but noticeable performance gain and a nice rorty exhaust note without being loud enough to annoy or attract unwanted attention from the authorities.

Then you get to listen to the new exhaust all the way back from Geelong. Nice!

[Ned Loh]

You should also factor in that the Cat will probably be stuffed if it hasn't been changed so you may really be looking for a complete system but thankfully the standard headers are pretty good.Some T&C systems have given up to 10 or so RWKW improvement when the cat has been stuffed,same day tested on the same dyno.

Peter.

As most people on the forum will know I am a friend of Colin at T&C and have helped with testing the systems but have no financial interest .

Replacing stuffed parts can't really be counted as a gain from exhaust modifications. Do you know what the gain is when using a cat in good order or retaining the same cat?

[pcmx5]

Yes typically around 4-5 RWKW increase on a car with a good cat and some midrange increase in both power and torque,Chris H had a cat and system put on a 5year old 30,000klm NB8B and it went from74 to 82 RWKW on a DynoDynamics,which was from memory the best gain.You wouldthink that some was from the steel high flow cat,even if it was replacing a good OE one.
My NA8A went from 66 to74 at the start of its developement.

As always some cars have more power to start with and get better improvement,not all are the same

Peter..

[NitroDann]

The stock headers are garbage.

Pls dont comment that they are good, cut some open..

Dann

[rascal]

The stock headers are garbage.

Pls dont comment that they are good, cut some open..
Dann

My NB8A had a proper cold air intake sourcing from outside of engine bay, hi flow cat, and free flowing exhaust with standard headers.
Swapping the factory headers to a Warren Heath set of extractors made the grand sum of 1kw difference to peak power. 78rwkw to 79rwkw up from 72 when 100% stock.
Admittedly there was a good mid range bump of 4-5kw, but since most people's focus (wrongly or rightly) is on peak power, then the factory headers getting within 1kw of decent extractors is 'pretty good'

[pcmx5]

We have had very similiar experiences with headers only making a 1KW or so difference,so while I respect Dann's expertise I am not going to recommended getting rid of the NB headers on my experience.I suppose you could only tell by doing back to back dyno runs with the same cat and system,one with OE headers and one with aftermarket.The couple of times I have seen dyno runs withT&C systems and aftermarket headers they have not been much different to others with the OE ones but I guess it wasn't the same car.

Don't want to start a bunfight it is ok for people to have different opinions/experiences.

Peter.

[NitroDann]

Nb8b are not bad.

The rest are garbage. 5kw midrange is huge it's more than 5%, where it matters too!

Dann

[pcmx5]

Nb8b are not bad.

The rest are garbage. 5kw midrange is huge it's more than 5%, where it matters too!

Dann

OP has an NB8A.
Have had good gains with headers on NA's though.
Peter

[Ned Loh]

The stock headers are garbage.

Pls dont comment that they are good, cut some open..
Dann

My NB8A had a proper cold air intake sourcing from outside of engine bay, hi flow cat, and free flowing exhaust with standard headers.
Swapping the factory headers to a Warren Heath set of extractors made the grand sum of 1kw difference to peak power. 78rwkw to 79rwkw up from 72 when 100% stock.
Admittedly there was a good mid range bump of 4-5kw, but since most people's focus (wrongly or rightly) is on peak power, then the factory headers getting within 1kw of decent extractors is 'pretty good'

Any details on 'proper' cold air intake? I have seen the typical air filter on silicone elbow (sucking engine bay air) do nothing.

Apologies to the original poster for getting off topic.

[rascal]

My NB8A had a proper cold air intake sourcing from outside of engine bay

Any details on 'proper' cold air intake? I have seen the typical air filter on silicone elbow (sucking engine bay air) do nothing.

Apologies to the original poster for getting off topic.

Custom made Stainless pipe straight off throttle body down to filter in the front air dam, receiving air from a hole cut in front bumper.
Datalogs showed IATs were same as ambient. Not like the 50+ deg you'll see from a pod inside the engine bay.

[NitroDann]

Correct length is far more important.

Dann