VandyZ

iTrader: (2)

From many dyno tests we have seen that plenum and cats are a good combo.

I am sure others will agree, but they do complement each other in that one helps it get air in the other helps it get air out. If you only concentrate on one side then you limit your potential.

Also the exhaust is the last thing I did to my car. Its kinda sad how little power I got out of the most expensive part I put on my car.

rednezz

iTrader: (1)

I can not wait!

Will it fit with the stock strut bar?

dwnshift

iTrader: (1)

At this point in time....the main goal will be determining the correct design to make a substantial and useable power gain. The strut bar will be something to take in consideration for the final design for final production.

I can promise this........it will be done 100% in everyway.
Those that have seen or use our upper control arms, sway bars, 3.9 final drive. and other products.... can attest to quality and craftsmanship that our products offer.

We have a target price in mind that I think is very reasonable for what we will be offering........it would be in the range of a full exahust system.....final pricing of course is a little ways dwon the line.

SPRacing

iTrader: (8)

If some one was to go Turbo, would you guys recommend a plenum or leave the stock?

lhas

Rather than the plenum spacer, why not go with a UD pully kit. You will definantly see a difference in performance.

xephiron

For the technical types, add this to your pros and cons:

A Kenetix V4 Racing Plenum is 4 lbs. lighter than the stock plenum, where a spacer would be actually adding weight to the car hehe, you asked for it...

Not to mention (like earlier stated) doubling your gaskets/mounts with a spacer can't be good long term. And it doesn't solve any possible plenum flow issues.

And doing a plenum/test pipe (or HF Cat) combo makes total sense. You have to increase input and output to make each other effectively increase. Go to McDonald's and buy a straw... make a 90 degree bend at both ends, and blow into it. Observe air flow.... now take the bend out of only 1 end of the straw and blow into it, see much change in airflow? NOW... remove the other bend, so you have a straight straw, and blow into it. I am confident you will have the best air flow now

Honestly, it is really simple. Don't do headers, HF cats/plenums, and exhaust and leave the entire intake system stock. Gonna cost you $2500 for, well... a much louder sound? oh, did I mention the 7 horsepower?

ReavTek

iTrader: (1)

I still think crawford has the best option when it comes to the plenum. Spacers are a band-aid to the problem. The crawford plenum (or even Kinetix) offer superior gains and quality. Also, I would keep an eye on the 35th Anniversary Z's Lower Intake Plenum, could provide gains.

copba1t

iTrader: (2)

That's funny, all information coming in so far, including independent dynos, says you are flat out wrong.

Do you have any proof to back up these statements, or do you just prefer putting big shiny things on your car because someone wants to sell you one

VandyZ

iTrader: (2)

First let me say this is me talking (Adam) and for some things in this post I wish I could take the sponsor title off my name. These are my feelings and not necessarily those of Crawford Z Car.

The dynos I have seen have been lacking if you ask me. I see several red flags just looking at the runs and the numbers form the chart vs. the numbers in the spread sheet. It seems everyone is confused about what spacer is being used where and what are the real numbers. From what I can gather your dynos are correct (if you are not swayed by the misleading text and talk). They show the minimal gains that was found 2 years ago when the spacer was first tried. Sure its gonna make some power . . . congratulations!

He has as much proof as you do, so what give you the right to question him. At this point all you are over here doing is giving your opinion and telling others that their opinion is wrong. It is not necessary nor acceptable.

I remember when you got into it with PhoenixINX. It seems now you were the pot calling the kettle black if you ask me.

Just let people make up their own minds. Lets leave it at this: For $245 you could have the spacer that would appear to be the best option for “money vs. gains” (but requires strut bar) OR for about $100 more you could have had an entire plenum replacement (also requiring a strut bar) with increased volume, enhanced flow characteristics, minimal interior interference, nice powdercoated finish that also has thermal benefits, and larger throttle body opening.

350zdanny

I have always been a fan of Crawford's plenum as a valuable mod and I really like the Kinetix design. If it was my money, I would buy a completely redesigned plenum (and I did), because I can afford to spend a few bucks more to make sure I'm happy.

Either way, you're not gonna notice too much of a gain from a plenum, so buy the product that makes you happy to drive your car. I personally didnt like the idea of adding an additional gasket and inviting a vacuum leak (so I didn't really consider the spacer). And I like the looks of the Crawford and Kinetix plenums.

In my honest opinion, dynos are a pile of subjective ****. They're great to judge relative performance on your car, but there are so many variables that the error is huge.

Zivman

iTrader: (19)

These are exactly my thoughts. If the cost of the plenum far exceeded the cost of the spacer, the spacer would 'hold water' so-to-speak as an alternative to a full plenum replacement. But as it stands now, the minimal difference in price and not addressing the flow issue are 2 big drawbacks to the spacer.

I just got my plenum yesterday and the throttle body opening is about 1/4" bigger than the stock opening. This is another benefit to the full plenum replacement.

Hydrazine

iTrader: (53)

“Red Flags” & “if you are not swayed by the misleading text and talk” Slinging mud like this is un professional.

Everything I have ever posted about the Motordyne plenum spacers has been absolutely true. All testing has been scientifically controlled and objective. If you can’t understand the language of engineering don’t comment on it. If you do, then say exactly what is wrong and where. Be excruciatingly specific.


And you keep suggesting the stack of gaskets you tested long ago provided minimal gains but you never show the dyno to prove it. Spacers aren't gaskets anyways.

E K’s dyno showed The Motordyne 1/4" Plenum Spacer @ $195 outperformed the Crawford V5. No misleading here.

Even if the Ľ” spacer produced 50% to 75% of the gains of the cast plenum it’s still an attractive alternative. Like was previously said:
-keep stock engine cover
-keep stock strut bar (if applicable)
-keep stock plenum
-less than half the cost

Additionally:
- Total stealth with the 1/4" spacer
- Near total stealth with the 1/2" spacer.
- For any size plenum spacer used, the user never needs to hack the engine cover to get it to fit.

Some people might actually want the above features. Wouldn't that be crazy.

Theories can be conjectured and argued back and forth all day long so let’s not argue over opinions and speculation. See the “independent” dynos posted below. They were performed on other people’s cars, performed by the owners with as many as a dozen witnesses watching. The dyno machine doesn't have an opinion as to which mod it prefers, it only provides objective results.

Same car
Same day
Same dyno
Same tank of gas
Same ambient temperatures
Same coolant temperatures (192°F ±2°F)
Same relative humidity
Same ECU starting conditions
Same everything..... The car wasn't even unstraped from the dyno.

Can’t get much fairer than this. As for the direct comparison of the Motordyne 1/4" spacer against the Crawford V5, the ECU was reset before the first pull of each set so it can’t be said the ECU started on a different timing map.


See E_K's thread for his testimony:
https://my350z.com/forum/showthread....hreadid=107539

See Dizz's Dynos and reviews:
http://g35driver.com/forums/showthre...&page=12&pp=15


See Nutty Prof's Dynos and reviews:
http://g35driver.com/forums/showthre...&page=12&pp=15

One example of a review (from G35driver):
Tony just installedthe 3/8 plenum spacer for me at the meet today. I wasn't expecting a big power gain from the spacer since I was told around 5-7hp. Well, I didn't bother with the ECU reset and went on my marry way. Surprisingly the power increase is very noticeable at least to me. The engine definitely pulls harder even at lower rpms. I could feel the difference even in normal driving at 3000-4000rpm. The additional power feels like how my coupe behaves on a very cold day with dense air - except it was fairly warm today inland so I know it's the spacer. The plenum spacer is not like CAI or Z-Tube, it works very well and gives you the best bang for the $$$ power increase IMO. Highly recommended.

ZinMiami Review:
https://my350z.com/forum/showthread....hreadid=109824

Yammy2 Review:
http://www.350zmotoring.com/forums/s...threadid=21508

Some people prefer independent subjective reviews over objective dyno results. Hey that’s equally valid. See multiple rave Reviews:
http://g35driver.com/forums/showthre...ghlight=spacer
(I didn't make this stuff up. Nor did I ever anticipate it.)

Inventor Classifieds:
https://my350z.com/forum/showthread....hreadid=108035

For more specific details on the Motordyne 1/4" plenum spacer Vs Crawford V5 comparison see:
http://g35driver.com/forums/showthre...9&page=1&pp=15

You don’t need to come out so strongly against plenum spacers. I know your product works. Just leave out the mud slinging. It’s only a little competition.

Tony Colette
Motordyne Engineering

PS More independent dynos will be posted.

Zivman

iTrader: (19)

I read and evaluated all that before I made my purchase and I still chose the crawford over your spacer. I do appreciate the work you did on the dyno testing, but it was not and is not convincing enough for me.

Competition is good, but it is suppose to benefit the customer, and in this case, I am refering to your price. You're price is way to high for a tiny slab of metal. Just my opinion.

copba1t

iTrader: (2)

Hogwash. His opinion is wrong based on at least a dozen testimonials (on quality) and dyno proven results (performance), many of which are linked in Hydrazine's post.

I also thought it was funny how you say "you are over here" as if somehow I crossed that forbidden line into Z territory. You Crawford guys are really amusing

You know, maybe if you would have jumped on the chance to come out with your own spacer instead of just mocking the whole idea, you could have gotten a piece of the 150+ people that decided against your beautiful plenum and went with a spacer, many of whom are Z owners I might add.

Zivman

iTrader: (19)

The thing you don't understand is they were going to do a spacer, but it provided lesser results. You can say all you want, but anyone that pays more than $50 for that spacer is getting screwed right in the @ss.

Got Vasoline?

copba1t

iTrader: (2)

Yea, with engineering marvels such as a stack of gaskets, it's no wonder their spacer provided little to no gains

Hydrazine

iTrader: (53)

I can appreciate this. This is why more dynos are on the way!

Quote:

Competition is good, but it is suppose to benefit the customer, and in this case, I am refering to your price. You're price is way to high for a tiny slab of metal. Just my opinion.

You are vastly underestimating material, fabrication, part processing, paperwork, overhead and the level of work involved. Untill you do it your self, you have absolutely no idea or ability to comment on it. If it's so easy and cheap then try it your self and become a overnight millionare.

Even if the Crawford cast plenum or Motordyne spacer were made from pure platinum by NASA engineers for $14200, it wouldn't make it perform any better.

As far as benefit to the customer goes. I believe customer benefit is best measured by the ratio of HP/$. Not expensive bling factors.

If HP/$ is the unit of measure used to determine value. Plenum spacers vastly outperform any simple bolt on I can think of. Wait a minute... TEST PIPES! They can. Mabey NOS or FI could exceed it too but I havn't done the math on them.

Tony

VandyZ

iTrader: (2)

I am sorry you feel this way. I was in no not slinging mud, just expressing my thoughts. That’s why I said please don’t associate my comments with the Crawford business.

You keep saying "I". Are you copba1t? Because that’s who I was responding to.

And . . . I never said anything about the gaskets in my above post nor have I ever said we used gaskets to test for power. I said Doug has tried a spacer long ago, and no it was not gaskets. The time gaskets came into play was when we were testing for hood clearances and just to see if you could run it safely to try the spacer idea easily.


The reason I said it this way is because your sole intention when you first posted on this forum was to start crap. Your first few posts on this board did not benefit the my350z forum at all. All you were doing was getting into it with other forum members.

I was a Z guy before I was a Crawford Guy. I have been here since day one. This is my home forum so yes I feel a territorial obligation to protect my home from people who are here for the wrong reasons and do nothing but stir stuff up.copba1t

Zquicksilver

iTrader: (5)

WOW...

What a heated debate among “air flow” coinsurers...it seems all of you are very passionate about your products. This in the end is a great thing for everyone! I've been a product designer for about 6yrs with a physics and engineering background. IMO, the Crawford plenum is a superior product compared to the spacer, IT JUST IS. With increased air flow at the entrance, minimal structure points and added volume to the entire plenum itself, air flow is maximized to all 6 cylinders. Now this is my theory…note that I do not say equally, but maximized. If you think about the air flow dynamics of the OEM plenum, it’s similar to an air duct/ ventilation system in theory. It’s larger at the entrance point but tampered as the air is distributed thru the vent system. Very similar to our tapered plenum. I never thought of this analogy until reading all the comments and opinions in this particular thread.

Now, on the other hand, all these comments about the spacers…bla, bla, bla!
This is my conclusion; the “CNC” cut, angled aluminum spacer when used in conjunction with the OEM plenum, proper bolts, gaskets, and necessary hardware is physically superior to the stock setup when maximizing air flow, IT JUST IS.

For what it’s worth, this is why I bought the AAM spacer at the group buy point vs a competitors spacer or a completely redesigned and cast plenum. The cost of the spacer, while keeping safety and longevity in mind, is the BEST BANG for the buck period. There really isn’t an argument here, it doesn’t exist. The Crawford plenum is superior to the spacers, but when cost is thrown into the equation, the angled spacer wins in the end.


Zquicksilver

Z BOY

iTrader: (41)

Wow, i'm very impressed. i like how you think and how you express yourself. you totally settled this conflict, and gave props to both sides...you should be our secretary of state!