tchuck's custom intake

laminar airflow is required because the sensor is only reading a very small fraction of the total airflow surface area & for it to be acurate the small sample it does measure needs to be an acurate representation of the total airflow... laminar airflow means even straight & non turbulent... if it isn't laminar then the total suface area will not be even & a small portion of that measured surface will not be an acurate representation of the total airflow... if there is a more dense stream of air that happens to hit the sensor then it will think there is more total airflow than there actually is & if a more dense stream happens to be swirling & riding the wall of the sensor then the sensor will measure less airflow than actual... sometimes a screen placed in front of the sensor can help smooth out a turbulent flow & this practice was pretty common on a lot of domestics when mass air measuring was relatively young but it does also add restriction...
 
yeah, soons been busy with avitars :tongue: kinda hard for me to know for sure on the 12" thing, I mean it is a general rule I guess, but of course there are always exceptions to the rules too. I would think every intake tract will behave slightly different. ford has on occation put a mass air flow sensor right before the TB in some cases, but from what I remember I'm pretty sure that they all had an egg crate type screen right before that to straighten the airflow out too so...

why do you need it so close?
 
I'm trying to get the whole thing to fit between the plenum and the grill. The "whole thing" being the TB, MAF tube, filter (in my air box) and a transition to the stock inlet above the grill. It's definitely tight but I think I can do it with a different filter.
 
That's pretty cool. It's interesting to see how different people approach the same set of problems. I wish I had access to a machine shop... That would be da-:bomb:.
 
tchuck said:
That's pretty cool. It's interesting to see how different people approach the same set of problems. I wish I had access to a machine shop... That would be da-:bomb:.
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oooh - nice use of the new emoticon!

I'm with ya - I have a garage workshop that's pretty well equipped, but it's no machine shop. Even just a drill press would be nice...
 
9 months and almost no real tangible progress... That's a bit depressing.

Well, as you long time members have noticed, my intake project has definitely been pushed to the back burner by many things since I started. Most notably this thing called "life" which has been steadily gaining weight for the last year. Though I haven't really officially "given up" yet I can definitely understand now why my particular idea hasn't been done, and why aftermarket intake kits are so expensive; It's a HUGE pain in the ass for such a marginal benefit. [Insert "I told you so" here...
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] With a baby on the way, and my business in full swing, I don't get much time to tinker with the FX anymore. Combine that with my lack of metalworking tools/skills, and you get a recipe for stagnation. C'est la vie I suppose. Hopefully I'll finish it one of these days.

The basic idea hasn't really changed but some of the specifics have. I have a completed design that I'm not going to show you just yet, mostly because I'm trying to figure out how to make it feasible to produce, but partially because I'm not even sure if it will really work. I'm hoping that I can get some more time (and money) soon to have a prototype built, but until then I'm willing to admit that this project is in a fairly deep coma. Not dead, but if you saw it from across the room you might think it was.
 
I'll check back next Fall. I think I take a machine shop class then, and shipping to Portland shouldn't be too bad. :wink (2):
 

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They seem pretty flared, any worry about turbulence from air coming from underneath vs. air going straight into the ITB?

Also, AutoCAD or SolidWorks?
 
StuLax18 said:
They seem pretty flared, any worry about turbulence from air coming from underneath vs. air going straight into the ITB?

Also, AutoCAD or SolidWorks?
Click to expand...

Solidworks.

The flared ends are a constant radius 90degree fillet. Pretty standard for a velocity stack. Its a compromise between ideal and realistic constructability.. Right now all the parts aside from the mouth transistion are standard parts and sizes. Throwing a Fibunacci curve on the runners would seriously complicate fabrication (you up for that fab task?)

I'm using flowworks for the analysis, and the turbulence inside the chamber isn't as bad as I expected. It's far from perfect, and there is turbulence, but it occurs mostly below the mouth of the runners so that they see a relatively constant air mass rather than a "stream" which would be more subject to obstructions. The really expensive Cosworth plenum uses the same theory and in doing so almost completely eliminates the "unequal flow between cylinders" issue. The problem now lies in modeling the old plenum (it's on the long list...). I can optimize this one until the cows come home but without a REALLY accurate model of the OE plenum I don't really know how much of an improvement I am seeing... Like I said, it's on the "long list".


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Ah, I see, finding a balance between what is best and what is simple to do. Glad to hear you flow tested it, I was going to ask about that.

It has similarities to a lot of the other options out there so hopefully it will turn out well. Also reminds me of the LSx intakes.
 
StuLax18 said:
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It has similarities to a lot of the other options out there so hopefully it will turn out well. Also reminds me of the LSx intakes.
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That's been my motivation from the beginning; That the VQ35 plenum is crazy, and the only reason it's crazy is that it has to fit under the 350z hood / strut bar.
 
You could even just take the current design and fix the slanted part, since that isn't needed for us, and it would be better. Although something like what you are doing looks much cooler haha.
 
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