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Picked up my FX35 last month, now looking to get a bit more out of it.


Is the Crawford Plenum a common or best-bang-buck mod for the FX35?
I saw the Z dyno's, are there any dyno's for the FX or is it expected to be similar gains? (I assume our tranny gearing is also different).

The only downside I see is the 4 smaller bolts you place inside the plenum. Yes, they do have loktite, but if they come loose/out are they going straight into your cylinders?


thanks!
 

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The only downside I see is the 4 smaller bolts you place inside the plenum. Yes, they do have loktite, but if they come loose/out are they going straight into your cylinders?
They fit in there really tight.

I think I overtighten mine.

This mod has been around for over a year, and have never heard of anyone having a problem with these bolts coming loose.
 

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APS is coming out with an aluminum one w/out needing to exchange your original. Also, z-tube/pop charger and UR crank pulley are good intial bolt ons. If you want any more than that then go for some headers and an exhaust set up. After that you realize for a little more you could have gotten a supercharger and shake your head :p
 

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APS without the exchange sounds good to me, does anyone know about when they will be released into the market.

Jim
 

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target date is Nov.
 

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APS release date at the SEMA show 1st week of November. I'll try to get more info once I'm there.
 

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I apologize guys because my intentions win what i am about to say have no negative connotation nor do i intend to talk down any products....

The Crawford plenum actually didn't show that great of a dyno increase to make it worth the money..... there have been air leakage issues, and most importantly, the Crawford is designed in such a way that the slant of th plenum towards the front of the engine actually cause turbulence in the first two intake ports which can cause the engine to lean out and get enough air into the first two cylinders cause detonatin or starvation.....

The Aps plenum will theretically be an awesome upgrade with such great potential gains.... but what people don't know is that the plenum is designed for a high flow forced induction system..... so if you aren't supercharged or turboed..... IT REALLY WILL NOT MAKE A DIFFERENCE.....

Just wanted to clear up any questions people had.... And Sweet Fxi know that you have the Crawford Plenum, doesn't mean that you made a bad choice at all, just that it's not all it's cracked up to be....

Always lookin out for you guys,
-Alex B.
 

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AlexAtMyNismo said:
I apologize guys because my intentions win what i am about to say have no negative connotation nor do i intend to talk down any products....

The Crawford plenum actually didn't show that great of a dyno increase to make it worth the money..... there have been air leakage issues, and most importantly, the Crawford is designed in such a way that the slant of th plenum towards the front of the engine actually cause turbulence in the first two intake ports which can cause the engine to lean out and get enough air into the first two cylinders cause detonatin or starvation.....

The Aps plenum will theretically be an awesome upgrade with such great potential gains.... but what people don't know is that the plenum is designed for a high flow forced induction system..... so if you aren't supercharged or turboed..... IT REALLY WILL NOT MAKE A DIFFERENCE.....

Just wanted to clear up any questions people had.... And Sweet Fxi know that you have the Crawford Plenum, doesn't mean that you made a bad choice at all, just that it's not all it's cracked up to be....

Always lookin out for you guys,
-Alex B.
I'd have to disagree with that. Don't knock it until you've driven one. :D
 

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BTW, I've had my A/F checked and though it is slightly leaner than default, it is still well within safe limits and running a bit rich for max power overall. The stock A/F setting is set conservatively on the rich side, so leaning it out a bit is a good thing performance-wise.
 

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Alex,

Good info to know. I'll ask them about non-forced induction applications.
 

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You guys are right.... Leaning out might not be a big problem, but the turbulence in the manifold can cause more stress on the intake valves and the quality of a/f mixtures between just the two cylinders... this info was based of an animation i saw a while back as well as some tech reports that explained how all the magic happened........ go figure on why crawford overlooked this factor....

-Alex B.
 

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Oh, well, if you saw it in a cartoon.... :roll:

Crawford used a flow bench to determine that the front cylinders were being deprived of 30% less air than the rears due to the sloped design of the plenum. Their modification reduces that differential to a mere 5%, so I don't see how you can say turbulence inside actually starves the front cylinders of air. Besides, the Kinetix and APS do the exact same thing; they're just manufactured pieces, while the Crawford is a modification of the existing piece.

Tell you what, I'll shoot Doug or one of the guys an e-mail and let them address this. Nothing against you personally, but as I am the unofficial Crawford plenum champion, I'd just be like to be able to get the facts straight.
 

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I was trying to post these remarks last night,but the site was up and down.
The art of plenums/intakes and heads is a combination of science and art.Nascar and drag racers spend a lot of $ on designing these parts.As Piniti relayed a conversation he had with Crawford ,it was clear that he understood these issues and I am sure his plenum is an improvement.However,more air/bigger as in the APS does not equate to best nor does the reduction of flow(CFM-cubic feet per minute) differences that each cyclinder needs at max rpm/lift/duration and balancing out torque as you get best flow.
Simply said it probably is a big improvement,is not the same as saying there could be something better.
In racing we send the plenum,intake,heads to the same person(hopefully a very good one),the issues are way past port matching,but flow/hpcurve/torque curve maxing.
And this is way past CAI designing.
If Crawford is the top of this pile great,but best may still be around the corner!!!I have noticed that some of the drag 350Z use a diff plenum.This is real $ and careful decisions are better decisions.Obviously Crawford works...that is not in question.

I was reading Hot Rod last night and someone came out with a new plenum for the Ford 4.6.4"taller and fits under hood,with Xhp gain.Development continues...that is not a new design motor.

PS I do not know what "Crawford Plenum Champion" means.I think we/I share the best info on parts available,hopefully at the best price and we all benefit!If one of those "turbo air spinner" things actually works,I would try to find the best price for folks.
 

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take a look at the '05 G cars, with 20 more HP they may have already done one or more of these common upfront/1st mods. These G's now have more HP than current or previous stock Z's! WOW! If they can do it on a G why can't we?
 

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Maybe I should hold off on the plenum and wait till crawford create one for the new G and more horses?


Jim :p
 

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I've had this debate through my head so many times...buy the plenum or not? I'm holding back to see what the future will bring, hoping that a price war will erupt between all the plenum manufactures and will bring down their prices. I've waited this long, so I'll see what springtime will bring. I'm very happy with just my Z-Tube & Stillen CAI Box. I'll probably get UR pulleys next.

Which will be more beneficial...pulleys or plenum? :?
 

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infx35 said:
Which will be more beneficial...pulleys or plenum? :?
Plenum.
 

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MustGoFastR said:
infx35 said:
Which will be more beneficial...pulleys or plenum? :?
Plenum.
Thanks Must!
Looks as I'll wait until next year to add more mods. :)
 
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