Wired 24/7

iTrader: (2)

I, Mike, AKA Wired 24/7, believe the 350Z was very well designed by the factory. Performance on par with the circa 1999 Porsche 911, unmatched styling, and a loyal fan base to boot.

While what I am going to post in this thread may seem obvious to most of you, and redundant, I hope that at least a handful of people will read it and understand what I am trying to accomplish.

I have investigated what I believe to be the key weaknesses of the 350Z and now I am attempting to overcome them, to see the true potential of a stock 350Z.

You may disagree with my definition of the term "stock." But I mean it when I say "stock," so please read on.

My mission, as of 5/10/2006, is to own the best stock 350Z out there. Stock in this case is loosely defined as stock intake, stock pulley, stock headers, stock exhaust.

My key points are as follows:

1) Primary restrictions above lower collector / lower plenum runners

Well, it seems Tony @ Motordyne has created quite a stir by challenging some of the "big boys" such as Kinetix and Crawford, who have both created aftermarket plenums. However, no one comes close to the hard research that Tony has been attempting. Virtually limitless different configurations of 287hp motors, 300hp motors, Z's, G's, aftermarket plenums, modded cars, stock cars, and more have made proving the performance of Motordyne products a virtual impossibility. However, in the midst of all of this, more and more proof is emerging, making Tony one of the biggest influences in the 350Z community, even in comparison to Sharif @ Forged Internals or our boys at Performance Nissan.

When I tested my 350Z with the MREV2 I was immediately impressed and shocked to see the roughly 13hp difference from stock on the DynaPack.

Addition of the 5/16" spacer caused the AFR to lean out significantly and thus the ECU pulled timing. The potential seems to be there. Will it make more power? We will see. Read on.

2) Primary exhaust restriction AKA the catalytic converters

Any high-performance car manufacturer must cringe at the thought of putting a catalytic converter in their exhaust system. However, they are there for good reason. You can argue all you want about "test pipes" or cat-delete systems. But in the long run, catalytic converters have made a huge difference in automobiles, pollution prevention, and are a necessity in my opinion. I am researching new catalysts at UCLA. Not for the purpose of catalytic converters, but my research will hopefully change the way people look at catalysts altogether.

With few options on the market for higher-flowing catalytic converters, I opted for the most economical I could find, namely the Kinetix. Due to unreliable manufacturer's claims, I cannot accurately assess the difference between Crawford and Kinetix cats. Therefore, the low cost option (and complaints about Crawfords cracking) became the clear winner.

After the primary exhaust restriction is dealt with, my VQ35DE should enjoy a lower backpressure on those exhaust valves while keeping exhaust gas velocity as high as possible within the stock exhaust system. I hope that this effect will serve to increase torque and horsepower everywhere in the RPM band, not just up top.

3) The strange and virtually un-tunable stock ECU

With the addition of the 5/16" spacer, my ECU decided it was a good call to pull timing due to the lean AFR. This resulted in reduced power throughout the RPM band. So, I am running a little lean down low and a little rich up top. Will the ECU adjust to optimize horsepower while maintaining engine safety? Will it jump to a different map randomly, and cause the car to behave differently? Will it speculatively advance timing to make more power and cause detonation and possibly a blown motor? Who is to say?

While technosquare may have figured out the stock ECU, not many others have.

I am going with the Greddy E-Manage Ultimate and hoping for the best. All I hear these days is "UTEC UTEC UTEC" but when it came down to it, the only dyno operator I know who I would like to tune my car happens not to like the UTEC interface. Well, while in a perfect world I could just get the "best" system and get a perfect tuner, sometimes you have to make some sacrifices. Frankly, I believe that over 70% of the people promoting the UTEC have never seen one, used one, data-logged with one, or tuned a 350Z with one. It is similar to semi-noobs popping into a thread to say "I've heard the JWT clutch is the best" or "APS TT is the best F/I" or even "Get the JWT popcharger!!!" Sometimes, noobs, you just need to STFU if you do not have personal experience with a product. If the Greddy doesn't work out for me, I will sell it and get a UTEC first thing.


In conclusion, I have a baseline dyno, and I am making the minimal changes to exhaust while keeping it mostly stock, and finally, I will get a tune.

I will post the results in here for the sake of all to see.

My baseline was about 258 hp at the rotors using a DynaPack. Who knows what the new mods will bring and what kind of numbers I can expect with the tune?

Wish me luck, my goal is to have the best "stock" 350Z out there. My goals may change, but that is life.

halitosis

I'll be monitoring your progress; this sounds like a worthwhile and rationally examined challenge for the ultimate stock NA Z. Good luck.

halitosis

.

halitosis

.

halitosis

Oops, I had internet issues.

MODS! Please delete my last two posts!

liudacris

iTrader: (6)

don't forget about suspension

Gary King

iTrader: (19)

Cool post, had a Mission Impossible feel to it, was waiting to read, that this message will self destruct in 10 seconds. Anyways, looking forward to hear your results.

JDMFairlady21

iTrader: (9)

nice i'm going to be keeping an eye on you too!

o snap its eric

iTrader: (5)

so basically what your saying is you hope to make your own high flo cat that flows better than the crawford and kentix that will set you apart from everyone else? Because most people on this board already if not going to have the MREV2 and a reflash or piggybacked ECU already and they should be up to par with you in term of power given that have the same baseline HP/TQ. I dont see how you can claim/make the best or strongest "stock" engine just by doing the 3 things above listed. Is there something your not telling us that your doing too?

As far as high flo cats are concerned, have you looked at the e46 M3? I believe they use fine mesh metal in their cat for filtering. Then possibly taking a look at some of the super cars out there with their huge diameter cats for physical design. If you made a cat that flows just as well as the TP and reduce that drone/rasp that i have i'll definitly would ask you to make me one

sja177

iTrader: (1)

Dood, you need to do A LOT more research about cars and the 350Z.

Z BOY

iTrader: (41)

ypipe.

Wired 24/7

iTrader: (2)

Whoa... I'm researching laboratory catalysts, not catalytic converters. I cannot and will not make a cat for anyone's car

What I'm saying is simple, make small modifications to the stock intake and exhaust system and then get a good tune.

The end result will be a car that is basically stock in appearance of engine bay and exhaust system. It will sound stock , only it will have quite a bit more power and the ECU will be optimized and not self-adjust. That is my goal, yes it is simple.

Matt - I know the stock y-pipe is not the best design. However I have yet to find an aftermarket y-pipe that has the same inlet/outlet specs as stock. If I get an aftermarket y-pipe that is bigger than stock, and bolt it up to the stock b-pipe, it will create a restriction and lose power. Maybe I can make one myself, in the student machine shop at UCLA. However I have never welded or mandrel bent anything before in my life.

taurran

iTrader: (18)

I haven't been too impressed with the quality of Kinetix problems in the past. It seem they have a habit of putting VERY LITTLE R&D into their products, and instead are content with releasing revisions after customers run into problems concerning quality, which is a very bad business practice, imo...

Motordyne seems to be doing great with their product lineup. They haven't really provided significant power gains above and beyond any of the other plenum modification. However, they have beaten all others in the category of PRICE. A simple $200 plenum spacer will perform on par, if not better than, the overhyped lump of crap that is the SSV. That's where the real value in the Motordyne products has been.

Wired 24/7

iTrader: (2)

I hear you. Hopefully my kinetix cats will be okay.

This also brings up the hidden message in this post:

mrev 2 + spacer: few hundred $
high flow cats: few hundred $
engine management: few hundred $
tune: few hundred $

Some people are paying more than $300 for CAI, a few hundred for pulley + install, headers for $500 + install, HKS dual exhaust is $1400, ALL WITHOUT DOING ANY RESEARCH. Then in HINDSIGHT they post a thread "should I get a tune or reflash" ... it just doesn't make sense to me. I have a plan and I'm sticking with it. That's all that this is really about.

Z BOY

iTrader: (41)

nismo?
also, https://my350z.com/forum/intake-exhaust/113077-cheap-and-effective-ypipe-stock-bpipe-mating.html
ps: my kinetix hf cracked. i really think they should be connected to the frame for support like the stock ones.

Wired 24/7

iTrader: (2)

For now I'm staying all stock in the exhaust except the cats. There is still a possibility for getting a catback exhaust in the future but it is not in my plans for now. I am still leaving open-ended the possibility of going F/I and as you can see, I haven't purchased any mods that are worthless for F/I.

What did you do to resolve the cracked cats? Will welding them do the trick?

Z BOY

iTrader: (41)

ya, a friend tig welded them. problem solved.

taurran

iTrader: (18)

I had some Kinetix HFC's when I was NA. When I got them they looked like total junk and had HORRIBLE quality welds. They worked fine until one day one of them just cracked in half on one of those crap welds. Luckily, Kinetix does have good customer service. They were able to replace them with new ones, only requiring shipping costs. After that, I put my stock cats on and sold the new Kinetix HFC's...

As far as gaining power, the only real way to go with this car is FI. I woudln't recommend buying any parts for an NA buidup that cannot be used in the future FI option of your choice. I made the mistake of putting some NA parts on my car (headers, y-pipe, etc) in preparation for a Vortech SC. I just ended up having to sell them after the turbo install and ended up wasting a lot of money.

undrgnd

iTrader: (2)

wired 24/7, you seem to have limited yourself to a small number of areas on which to concentrate, for no good reason, almost arbitrary at best. The Y-pipe and rest of the exhaust system mods have netted serious gains, and I would argue that my system looks just as good and just as stock as yours (amuse r1 and jic bullet y-pipe). Frankly, I don't see any benefit at all with what you are saying or trying to accomplish, but good luck anyway.

Goofy1477

iTrader: (11)

Wired--- I would also suggest a 3.9 final drive. That will change the car dramatically. Best mod I have done, and you can't tell by looking at the car you have changed the gearing.