Price points aside, actual power production aside. The two Y-pipe's (Unlimited tuning $395 and the Fujitsubo $349) differ in one critical way. Unlimited's is ment for those that have 65mm pipe diameter down stream, which is what the oem pipe diameter is. The Fujitsubo is ment for those that upgraded their system's down stream and have larger them oem pipe diameters after the Y-pipe since the Fujitsubo use's a 76.3mm collector. You do NOT want to marry a 76.3 collector output to a a 65mm flange, not unless you want a nice large lip and restriction in the flow path. Of course you may be buying a Y-pipe with down stream upgrades in mind latter on.

A better Y-pipe to pit against unlimited's is Kinetix's pending Y-pipe which will sell for $349, has the same collector diameter (65mm) and use's a design that is a copy of the Jic Y-pipe.

 

If this is true, and i understand you correctly, since i am completely stock underneath and plan to upgrade only the cats and ypipe, i should purchase a ypipe with a 65mm diameter, which the fujitsubo doesn't have.
Care to comment on this, Yuichi Kurosawa?

 

Please excuse my lack of knowledge re: exhaust set-ups, however as I understand it the Kinetix Racing y-pipe is designed to have dual 2.25" diameter pipes with a single 2.5" outlets (I have been advised by Kinetix that this matches up perfectly to the stock exhaust ) and the Unlimited Tuning y-pipe has dual 2.25" diameter pipes with a single 3" outlet (referenced on website). So my question is, will Unlimited Tuning's y-pipe w/ 3" outlet also match up perfectly to the stock piping downstream?

 

Let's talk ypipe diameters in inches:
Stock inlets=2.25";outlet=2.5"(??? can someone verify this???)
unlimited's inlets=2.5"; outlet=3.0" (from their website)
fujitsubo-style gb inlets=2.38"; outlet=3.0"(http://www.my35oz.com/forum/showthre...threadid=83271)
Kinetix inlets=2.25"; outlet=2.5"
Why buy Kinetix if diameters are same as stock?
And we haven't even talked about weight comparison yet.

 

I believe the Y-Pipe is 2 lbs lighter than the stock one.

 

Maybe I should have taken Physics in High school

Because, Maybe Then, I would understand how (and WHY), simply replacing the mid section (or Y-Pipe) of a stock system will have More gains than ANY aftermarket Cat-back available. Mystifies me.

 

Ok, let me try and take a stab at this.
The stock y-pipe on this particular vehicle is designed for mass production, to keep costs down, designed to retain low end torque, and very restrictive, etc. etc.
Hence, replacing it with a better engineered, free flowing design will reduce restriction aiding in HP gains as seen on the Unlimited Tuning's y-pipe.

As for the the pple concerned about the 3" outlet mating to a stock exhaust, I wouldn't worry too much as ya'll seen UT's dyno gains on a stock 350z (no HP loss). Theoretically, 3" to 2.5" doesn't make sense but in this situation doesn't show any adverse effects,, therefore, its ALL GOOD BABY!!

Thanks to Unlimited Tuning for taking the extra step to test and introduce their products.

 

Everyone says the biggest restriction to flow and hp gains in the stock Z's exhaust system is found in the cats and the ypipe, and that aftermarket mufflers add no signif hp increases over stock. To my way of thinking, being cost-conscious and a real bang-for-the-buck shopper, it would be cheaper to replace the stock cats and ypipe than the header back. But i'm a newbie; wtf do i know, anyway. I could be totally full of shift.

 

Would someone offer some insight into this, please? There has to be a logical explanation for this.

 

i have seen the y-pipe in person, it's great.

Performance Motorsport will install this for you, and Dyno your car too.

Long Island, New Yorks ONLY Mustang Dyno.

0-60 runs, 1/4 mile runs, HP, TQ, and more...

Call us for your baseline dyno pull before the install, then another after the install for a special rate.

Dan Z

 

its because our stock exaust is really really good, while our cat's and y-pipe arent all that great.

 

Guys/Gals,

Our dyno proven Y-pipe is in-stock and ready to ship. Please call/email to place your order.

Thanks.
Ron
347-993-3469
info@unlimitedtuning.com