Well there you go. I presume it's only the muffler that's different?

 

LOL, Yeah I would say so.

 

Mate thanks for your post and many comments you made are very relevant. Fact is the APS cat back system is a true twin 2.5'' cat back system designed for up to 450hp applications and is manufactured entirely from 304 stainless steel (including all mounting flanges and hanger breckets and the system is fully TIG welded and mirror polished) so the APS design brief is most likely different to other local Australian exhaust shops who produce a system for the Z.

In addition the APS system is designed to meet the Australian mandatory 90dB noise limit, this also increases the cost of production somewhat, that is to design a muffler and resonators which meet the noise limit and can still cope with very high horsepower with minimum exhaust back pressure, and have a tough exhaust note when the engine is on full song and be oh so quiet when cruising in partial throttle conditions at speeds between 60 to 160 kph. There's nothing worse than an exhaust which booms and drones in normal driving conditions, so we have paid particular attention to this during the exhaust development.

We will conduct true back to back dyno testing of the APS cat back system and compare this to the stock OEM system and another popular cat back system, so I hope to have these dyno results for you guys in the near future.

APS's design brief from company directors was to produce a genuine world class cat back system which meets and exceeds the expectations of the most fastidious 350Z owner

Peter

APS

 

Peter - I'm sure the APS exhaust will be a nice product (I'm not sure what 304 SS is but I assume a harder steel).

What impressed me most about your response was this paragraph:

"In addition the APS system is designed to meet the Australian mandatory 90dB noise limit, this also increases the cost of production somewhat, that is to design a muffler and resonators which meet the noise limit and can still cope with very high horsepower with minimum exhaust back pressure, and have a tough exhaust note when the engine is on full song and be oh so quiet when cruising in partial throttle conditions at speeds between 60 to 160 kph. There's nothing worse than an exhaust which booms and drones in normal driving conditions, so we have paid particular attention to this during the exhaust development."

I hear a lot of WRX's on the road with modified exhausts and they sound tough with a rough and rummbly note at low revs. Althought I appreciate this as I pass by the WRX, as an owner of such a car, I could not put up with the constant exhaust noise from 1000 rpm day in day out.

In my Z, I generally putter along at 1500rpm in 6th gear (apporx 60km/hr) and when I hit 2000rpm (approx 70km/h) the engine / exhaust note is getting slightly louder and I costantly find myself clutching and looking for 7th gear (I wish Nissan gave the Z a 7th gear).

So an exhaust with a quite note at low rpms, that also sounds mean at high rpm is right up my ally. Perfect for my daily driving conditions and occasional enthusiastic burst.

I believe that you have assessed your target market for this product very well.

 

^^^^

I hate being under 3000rpm ... I have no choice in 1st but after that i stay up where the exhaust sings.

I must be hard of hearing in my old age.

 

The 304 is a higher grade of stainless steel than say a 409 grade of stainless which is common within the the exhaust industry, The 409 grade has less nickel content hence it's a lower grade of stainless steel and won't cope with higher exhaust gas temperature before the material starts to fail.

Well thats the secret of a well designed exhaust system, to achieve the best possible power result without all of the unnecessary noise,I don't like a harsh exhaust note, imo this spoils the experience of the drive and draws attention that's not always wanted (attention from the law) and gives many occupants a sick feeling on a long cruise.

Well that's good to hear and exactly what I believe most Z owners expect from a well designed and manufactured cat back system. I am confident that the APS cat back system offers an excellent blend of performance and exhaust note combined with extended durability to cope with extreme exhaust gas temperatures which is a by-product of high power.

Peter

APS

 

The worst is the constant droning from only upgrading the stock muffler to a dodgey performance muffler on a small 4cyl car with an automatic gearbox.

It just drones and drones and give you a headache in 5 mins.

 

You are right of course 4 cyl engines are definitely the worst for exhaust drones,and an auto trans makes the droning even worse, the next worst engine configuration for engine droning is a V6 engine and the Z car also has quite harsh NVH, this is why exhaust/muffler design is very critical on the 350Z.

Regards

Peter

 

If APS design their exhaust the same as the HiTech one but use a true dual setup then it should be able to beat the HiTech.

The Injen true dual got ~9hp didnt it? I couldnt find a dyno chart when i did a search just then. But thats like 8hp more than other exhausts, so the APS one might be able to get another 5-8hp more than HT. This would make for a very large gain from just a cat back!

Judging by the photos though the APS one looks bigger and would have more piping so its definatley going to weigh more.

 

I just can't see the APS exhaust doing anything better than the Hi-tech one for NA. It'll certainly be better for FI though.

At the price Hi-tech is coming out at it's a pretty good deal. In fact if you look up my dyno it's pretty amazing. I almost don't believe the dyno... !

 

If its too large for NA then I totally agree, it wont be better, it will loose too much at the bottom end. BUT if its like I said and uses the same muffler materials etc and they make it a real dual exhaust then technically speaking it should be better.

 

Well for what it's worth APS has conducted a back to back dyno test on the same car (against the other exhaust system) and the APS cat back system generated 3 more kW's of power............nothing to really rave about though not a bad gain over the opposition either.

What was interesting however we found another 11 kW's from dyno tuning the Z engine and optomising the air/fuel ratios and ignition timing, now that is very worthwhile.

Peter

APS

 

Sounds good! Can you post the dynos up so we can have a look?

It would be interesting to see the torque and power curve. Were all the gains up top like the Hi-tech?

 

I could post power graphs now though i would much prefer to wait until we have tested the APS exhaust system on a number of different Z cars, this way we can look at the average power gain across four 350 Z's which I believe is a more realistic overview of the real power gain from the exhaust system fitment.

We did not get to dyno the car with the stock Z exhaust system (as the car had a hitech exhaust fitted) so the only power graph we have for comparison is the APS cat back v H/T cat back system.

I will post power graphs on the APS web site when I have additional information which is fully verified over a number of Z cars.

Peter

APS

 

Did the Zed loose power or torque anywhere on the dyno chart against the HT?

Which computer chip did you use to tune the Zed?

 

No it was better everywhere (across th entire RPM range) at no time was the torque or power less than the H/T system.

Peter

APS

 

And which chip did you use to tune the car?

 

I'm presuming APS is using the stock ECU for this test!

 

They would have used the stock one with the Unichip solution or their own solution that is being used on the TT setup.

 

Well then that's not objective! Since the APS exhaust is better suited to the TT it'll be optimised with the UNICHIP.

If the Hi-tech somes within 3 kw of the APS in that situation i'd say it's actualy ahead. The Hi-tech was never built for FI.

It's always a compromise with these things, you are either better suited to FI or NA but not both. Same with the UNICHIP settings.