There is a local performance shop in the area that is working on some exhaust parts and they have prototyped a couple and dynoed them. They have made a straight pipe to remove the silencer and increase diameter and they have also made a y-pipe which is 2 1/2 each side going into 3" and will mate with original straight pipe or new straight pipe.
The base dyno was 237.2 HP and 231.9 TQ
Dyno with straight only was 242.4 HP and 239.2 TQ
Dyno with y-pipe and straight was 248.2 HP and 243.2 TQ

So I would guess that the y-pipe would be the difference around 5-6HP and 4 TQ.

It will be painted with Jet-Hot black paint and made of T304 Stainless and will be manufactured by Brullen exclusively for Japtrix.

The pricing will be as follows:
600.00 for both Y-pipe and straight pipe
350.00 for Y-pipe only

The straight pipe is 3" with a resonator and the Y-pipe is 2 1/2" into 3" and he is working on a muffler as well. The y-pipe will fit with stock straight pipe as well. He will make an initial run of 10 so let me know if you have an interest, right now you can order with 2 week leadtime.

I forgot to mention they will warranty it for life.

OK, he got the prototype of the y-pipe and straight pipe back, here are picks of them installed. This is not my car as I already have a Fujitsubo installed, I ordered before I met up with him so no a reflection on his straight pipe or soon to come muffler.
He will do dyno's next week again, one of the car stock, another of just the y-pipe and rest stock, then one of the y-pipe with straight pipe and stock muffler and finally one with the y-pipe and straight pipe and muffler.

The wieght of the y-pipe is 4 pounds less than stock and the straight pipe is 4 punds more than stock so both together are the same weight as stock. He will provide an option with Jet Hot coating, I should know final pricing later.

For those intesrested in improving their performance here is an option. There is a Y-pipe and straight
mid Pipe that can be installed together or individually and are straight bolt on replacements and
you can keep your stock muffler or replace it later with one being developed by the same people.

The Y-pipe is 2 1/2" on each side coming together to a 3" section and the straight mid pipe is 3" with
a resonator/silencer. Both are made of Stainless Steel T304, mandrel bent and are being
manufactured by Brullen for them. Weight is not affected as the Y-pipe is 4 lbs less than stock
and the straight pipe is 4 pounds more than stock.

Below is the Dyno with the base and straight pipe only followed by the dyno with the y-pipe and
straight pipe together, all runs where at the same place with a Dynojet. the numbers in summary are:

The base dyno was 237.2 HP and 231.9 TQ
Straight only 242.4 HP & 239.2 TQ increase = 5.2 HP & 7.3 TQ
Y-pipe and straight 248.2 HP & 243.2 TQ increase = 11 HP & 11.3

You can deduce that the Y-pipe account for around 5-6 HP, if you just replace the y-pipe you wont
get this much since the original straight pipe will be smaller but it is a great option for anyone with
aftermarket exhaust like myself to finish off the exhaust system since no system replaces the
y-pipe other than Stillen. I didn't get the straight pipe because I had already ordered the Fujitsubo
when he decided to start making these, but I do have the y-pipe installed.

The last picture is of the system installed, it is the prototype but the finish product will have the
brushed aluminum look.

Pricing is as follows:
Y-Pipe List=350.00 Group buy=315.00 (5 or more)
Straight Pipe List=225.00 Group buy=203.00 (5 or more)

So post or email me if you are interested and once we get enough people I will notify him.
Let me know which parts you want and your email address. I don't have shipping costs as they
will depend on whether individual items are purchased or sets.

http://www.sfzcc.com/images/scan0002.jpg
http://www.sfzcc.com/images/scan0001.jpg
http://www.sfzcc.com/japtrix%20005.jpg

hey westpac give me a ride in your 350z please

:D :D

Can you not just use a y-pipe designed for the Maxima or Altima 3.5?

The Maxima y-pipes are half the price of the ones for the Z.