From what I understand, most gains are in the upper RPMs. In terms of worth the cost; this is a simple bolt on. Relocating the strut bar is as easy as taking off the stock an putting it back on. I would say the only "cost" is the $ and not being able to use the engine cover without modifying it.

 

Dyno sheet is here:
http://www.crawfordz.com/pics/adamdy...ckvsplenum.jpg

 

Nissan didn't do a lot of things we wish they would have done.

 

Interesting info:
http://www.350zmotoring.com/forums/s...854#post271854

 

Read up. Best bang for the buck.

http://crawfordz.com/pics/adamdyno-stockvsplenum.jpg

 

I WANT IN!!!

 

looks like ill be ordering one of these after exhaust...! and crawford if you guys got any extra header laying around.... send um' this way

 

I've just heard that the 1/4 inch spacer between the upper and lower plenum has been dynoed. The results were based on the same car,same day, same dyno,= 6.5 more hp than the crawford v5 (WOW). He will be posting up the dyno soon on the other 350z forum.. And yes you get to keep the stock strut bar.. Decisions, Decisions..
screaminz

 

ALL DOUBTFUL

 

The dyno will be posted tomorrow on 350zmotoring so we've been told. I'm going to buy one or the other very soon..
screaminz

 

You seemed to forget the builder admitted the only "spacer" that might make power is the tallest... which will NOT fit under the Zs strutbar.

Come on dude... welcome to my350, but there is a difference between realism and nonsense.

 

no no, this was tested on a G. it will not fit with the stock Z strutbar.

but on the dyno, it seems that at lower rpms, it kept up with the V5, but at higher, it actually exceeded the V5 by 5hp or so. interesting. i wonder what both together would do.

any chance of making a higher plenum crawford?

 

They are trying the V5 and spacer, it fits so far, I believe they are doing a dyno soon to see if it gains even more.

 

A Crawford v5... with ANY spacer will not clear the stock strut bar.

Do NOT be mislead.

Hell, the version 5 BARELY fits under a Zs hood.

 

Not under the strut bar, I meant if fits under the hood so far. The spacer is 0.25".

EDIT:
Pic of it installed...


Quote: "Summary:
I know that we need more data, but the stripped threads put a wrench in our plans. What's probably going on, is that the spacer helps by changing where the air is directed coming from the plenum's neck. In stock form, the air is directed at the "hills" on the lower plenum. With a spacer, the air flows above those hills, and has a less restricted path. I'm now running the Crawford with a 1/4 spacer. There's no clearance problems on the coupe with this configuration. What I'd like to do is get the car back on the dyno in this config, but I have to fix the stripped threads first."



BTW, i'm not trying to say this is a better product. I plan on getting the Crawford cast plenum and this spacer to maximize airflow .

 

Went to the shop yesterday morning to help figure out some particulars on the plenum production. While watching some of the assembly I saw some ideas to help iterate what goes on inside of the plenum.
(Dont try this at home, unless you want to hack up a lower plenum)

Stock:



Cast Crawford:



Stock:



Cast Crawford:



Stock:



Cast Crawford:



Now, keep in mind that the runners were cut off and get even larger and more bottlenecked the further you get from the center. To illustrate this, here are some pictures to compare the cut piece used above in the pictures and a complete piece.

 

Well, to me it looks like a spacer would do a very similar thing as the plenium. Did you guys try to do any dyno runs or flowbench tests on the lower plenium with top of the runners cut off? That way they would be shorter and help with power at the top of the curve. Something that I'm sure few people would want with cammed engines. Also there would be less distance between the throtle and the cylinders aiding in throtle response. It might also increase the plenium capacity as well.

I think this is something that might have been done to the 2005 Track engine since there is talk about shortening the intake runners.

 

Who makes this spacer you guys talk off?

 

Yes . . .trust me, you dont want to modify the lower plenum. It has been tried several ways with undesirable results.

Also, please take discussions about non Crawford products out of this thread. Feel free to discuss in a secondary thread, but leave this thread for those interested in the Crawford Cast Plenum.

Thanks!

 

I know that doing that would loose low end tq and I'm aware that it has been tested. But what makes me wonder is if it has been tested on a cammed engines. This is where the benifits would be seen. Mostly if some one is using an aggresive cam like Nismo Spec-1 (276 degrees) or Tomei 268. I'm positive they would have something to gain at top end even if there is a significant loss in low end tq.