Z-Fever:Anatomy of a Custom Intake Manifold (VQ35)

[Z-Fever]

I am Doug from Z-Fever. We build custom cars and do a lot of custom fabrication. We are currently building a VQ35DE powered 280ZX (old school but cool). We had to make a custom upper intake manifold to get the OEM hood to fit without hitting the engine. So, I figured I would do a tutorial of what it takes to make a custom intake manifold from start to finish.
I hope you find it interesting and educational.
Enjoy....

We start by scanning the stock gaskets where the lower plenum meets the intake manifold and the throttle body gaskets. Once we do that we digitize them to work with our design software. The images look like this:



Then we create those 2D image into 3D images:



Then from those images we create the program that will tell the machine how to cut the blocks of stainless into these shapes. This program details the speed the machine rotates each bit, what type of bit to use on each cut, in what order to make each cut, and more. The finished products look like this:




From here we create the image of what we expect the finished part will look like. We take the finished 3D images and fuse them together into a complete image. We also rotate and measure as we go making each piece fit so that we can get to the bolts on the intake flange. We map out exactly where each mandrel bent 2" tube has to be welded to the flange so that the clearances are accurate. This is what that looks like:






Then we make the intake plenum side wall where the mandrel bent tubes meet the intake. We make this ONLY after determining where the holes need to go in order to be able to get to the mounting points of the lower flange:


Then we put all the pieces together and cut out the 15"x15" piece of 16 gauge stainless that the intake plenum will be made from, the 4"x7" pieces that the front and back plenum walls will be made from, and we start welding.

Here is a pic of all the pieces before welding:

Here are the (6) - 2" 90 degree mandrels:

Here is the folded 15"x15" stainless section:


We start by welding the mandrels to the intake side wall (you will see that the folded intake section is attatched to this side wall at this point but only to keep the side wall from bending and contorting its shape while being welded on):




Then we weld the mandrels to the lower flange:





Then we cut off the sections of the mandrels that are sticking through the side wall of the plenum:


Then we fit the rounded plenum section to fit the side wall. Making sure that the clearance to the valve cover is accurate and also making sure that we increase velocity of airflow away from the throttle so that the cylinders furthest from the entry point get an equal amount of air as the one's closest to the entry point:




Then we weld the throttle body flange to the 3" stainless mandrel intake pipe:


Then we weld the 3" stainless mandrel pipe onto the intake plenum at the angle we need to make the clearance to the valve cover and the hood.... It looks a little something like this:
(BTW... you may notice the Z-Fever logo plate on the intake tube. We already made the cold air intake pipe with the air flow meter flange we made welded to it rather than using the stock black plastic air flow meter housing, looks a ton better in IMO)






This shot offers you a good look at the inside of the intake after it is all together.


By tomorrow morning (maybe 30 mins after we open) we will have this all closed up and the engine will be running. We will post dyno #'s after we get them to see if we have any actual realized gains.

As always, I hope you appreciate our post.

[revcyanide]

looks a lot like a better made xcessive one, I am real excited to see actual gains!

[simmode1]

Lovely work! Is there any particular reason why you guys didn't go with a front mounted throttle body setup?

[atutt]

Hmmmmmmmm.... Is this piece backpurged? It's hard to tell but it doesn't look like it.

A lot of those welds look hotter than they should be. Could use a lot more practice to improve consistency.

[sexcii-zenki]

lol i want 1 but with the throttle pipe facing the right side...cant wait 2c the gains

[DreamDriveDrift]

How did you come up with the optimal design? In terms of runner length, runner diameter, shape of the collector, intake diameter, etc?

[s13dan]

First thing i noticed was how terrible the welds are on the intake piping.. Please tell me they are just being used for fitment, because the intake manifold looks amazing.

[conrad_s13.5]

This is awesome!!!!!!!!

need to add to the fab thread when/if it comes back....lol

[Highway Riding]

Kinetix look alike? I had one. Meh.. sounded nice! The cosworth's are nicer. Nice fab work tho..

[OBEEWON]

Good for biz!

[Bushido]

Bad ass.


Lol at the weld snobs... But this is zilvia right?

[NickZ32]

how bad did that flange warp?

[hOngsterr]

Saw your thread on the 240sx VQ35DE Turbo!

very nice work

[bardabe]

needs back purge lots of crystallization inside the plenum, why not make it aluminum?

[trainkiller]

finished product?

[codyace]

Originally Posted by careboy

Could use a lot more practice to improve consistency. Good job.

Are you speaking from experience or just posting to up your post count?


Sure we could pick it apart, but it looks fine and will undoubtedly make some power. Splitting hairs is one thing, but only on the internet do so many experts exist. Sure it could be better, but if it's already better than 90% of the junk created, what's the point in getting hyper critical?

[trainkiller]

Originally Posted by careboy

Could use a lot more practice to improve consistency. Good job.

wait are you serious?

Just look at a couple of build threads. These welds are pretty damn good, compared to some of them.

[Def]

Welds look fine to me, but the back of them needed to be shielded (backpurged or solarflux).

The weld-els have got to be heavy as crap though...

[revcyanide]

what happened to posting the finished product yesterday! : P

[sexcii-zenki]

Originally Posted by revcyanide

what happened to posting the finished product yesterday! : P

thats why i came for as well

[s13 @ fullboost]

look great can totally tell the quality is good and great craftsmanship

[tryangle]

got my ecu and harness from doug, great work and when the motor isnt having issues it runs strong as hell.

[R33E8]

Wow, how much does that weigh?? Why not use aluminium? I can only imagine it would be much faster and easier to machine and cut (and weld for me)...

[omgRWDgoodness!]

Originally Posted by Bushido

Lol at the weld snobs... But this is zilvia right?

Originally Posted by codyace

Sure we could pick it apart, but it looks fine and will undoubtedly make some power. Splitting hairs is one thing, but only on the internet do so many experts exist. Sure it could be better, but if it's already better than 90% of the junk created, what's the point in getting hyper critical?

These are probably the same experts who call this piece of fucking shit "Hella nice welding":

[90white240]

O my what the f#$K is that^^^^^

[pacotaco345]

Originally Posted by 90white240

O my what the f#$K is that^^^^^

DON'T TALK ABOUT MY CUSTOM FRONT MOUNT TURBO MANIFOLD LIKE THAT!!! lol jk, whoever made that should have his fingers welded together...

[conrad_s13.5]

*sigh,.. leave it to zilvia

[sexcii-zenki]

mr. doug...

still waiting on the end results...thanx

[Z-Fever]

Here is the finished product installed along with video






And video of it running:
Z-Fever built VQ35 280ZX custom intake running.MOV - YouTube

[Z-Fever]

Originally Posted by sexcii-zenki

lol i want 1 but with the throttle pipe facing the right side...cant wait 2c the gains

We did that already on our VQ35 Twin Turbo Drift S14:

Here is the pic: