JoesRedMax

iTrader: (1)

Well guys I just purchased an intake manifold from an 06 Max for 150.00 on Ebay. I am going to port and polish it myself. I will post pics when done. If it comes out good then I will do the same for my existing manifold then offer it up for sale here. I'll keep you posted.

Hilbe

iTrader: (3)

Are you going to do before / after dynos?

UnMaTcHeD

iTrader: (2)

If all goes well, I call dibs on your manifold.

Fastmax05

iTrader: (17)

and if he bakcs out i calldibs then

DeusExMaxima

iTrader: (1)

I suppose I shouldnt mention that I have an intake manifold in my garage since I have a Kinetix on my car?

Glude

iTrader: (5)

I want deus, SSIM mod and maybe a P&P.

EDIT: Hook it up!!

NmexMAX

iTrader: (22)

Before and after dynos should be considered a must whenever doing this type of mod. Especially this, since you can;t really go back and retest it, i.e. not as simple as an intake o remove/put on take off.

Glude

iTrader: (5)

I got a VIAS blockoff plate on the way so I can see how that is by itself, eventually I wanna spare upper IM so I can have my way with it though. Figured id try to get it taken care of so I can install when I get the IM gasket kit and maybe do the plugs too.

madmik

iTrader: (1)

Note: LIM, top, notice that port for cyl 2-4-6 (rad side-blue marker) are 10% larger than 1-3-5 (firewall side). On head side, ports are all identical in size. 3hrs to do the LIM.

LIM before


Removed casting leftover, leveled the bump before injectors, opened up 1mm to clean-up port, removed lip near top and opened up 1-3-5 mouth by 2mm. Polished with Dremel 120 grit.



Buffed with white rouge. Hard to see but it like chrome.


Just ordered the phenolic kit. Will then try to add 3mm more to 1-3-5 to match 2-4-6.

DeusExMaxima

iTrader: (1)

I was gonna port mine too when i did my spacer. i wonder how much difference it will make?

madmik

iTrader: (1)

More air = more power. The polishing will primarily help top end. My hope is 3-5 hp. Opening up the 3 smaller ports could add up to 5% better flow overall (being optimistic). Will this give 5% more hp, probably not, more line 2-3% more (5-9hp). I am hoping for 10-12hp near the top. The phenolic spacers is good for 10hp in the middle. So, 10-12hp from 4k-6.5k would be nice.

DeusExMaxima

iTrader: (1)

How long did the job take you? Was it 3hrs as u mentioned initially?

nismology

iTrader: (8)

The diameter of the openings in the LIM are staggered for a reason. Due to the unequal length of the runners in the upper manifold every other opening was kept smaller to more or less equalize the total volume of air entering the intake ports by increasing the velocity. Just in case anyone is wondering.

NmexMAX

iTrader: (22)

In other words, 'cept for 98% of people on here, then you might be able to relate even on lucky day....

And those who cannot comprehend the physical sate of exhaust flow/

DeusExMaxima

iTrader: (1)

I have a Kinetix intake which has equal length runners. It would seem that my car would benefit from porting, right?

NmexMAX

iTrader: (22)

No dyno no care.

madmik

iTrader: (1)

The LIM took 3 hrs but I took my time. Much less if you are a Dremel pro. The UIM is next and should be much quicker.

madmik

iTrader: (1)

If you look inside the UIM, the top 3 runners are recessed by one inch. I used a piece of pipe insulation and the 6 runners are all about 6.25” long. The LIM runners are about 4.25” long. Total length about 10.5”.

My take on fluid dynamics and resonance:

Each cylinder sucks a volume of 36.3 cubic inches in one down stroke. Ports 2-4-6 have an area of 3.68 inches. The column of air displaced in each runner is then 9.9 inches long, which fits in a 10.5” runner. Ports 1-3-5 have an area of 3.36 inches, thus a column 10.8 inches long, which is a tad longer than the runner’s length. So, enlarging runners 1-3-5 should balance the volume and will keep all 6 cylinders flowing the same.

It is quite possible that NISSAN is trying to get each bank to provide peak HP at different rpm, or maybe just to limit top end power. There is Helmholtz resonance at play here and I have to do more reading on this.

DeusExMaxima

iTrader: (1)

Good stuff man. Keep us posted. Also, inform on the Helmholtz resonance. Also, possibility of a Bernoulli effect in having smaller lower ports to increase the air velocity?

madmik

iTrader: (1)

If the 6 runners have the same port area size, then port matching at least. You have 3 runners (1-3-5) flowing through ports on the LIM 10% smaller. Unless Kinetix has made these 3 ports smaller.

DeusExMaxima

iTrader: (1)

The runners on the Kinetix are identical.

madmik

iTrader: (1)

Helmholtz; everytime a valve closes, the shock wave goes out to the plenum and back towards the valve. With the correct runner length, it creates a little push on the next column of air just when the valve opens, so you pack a bit more air into the cylinder.

The LIM's lower ports are smaller. That is where the injectors are located. Increasing velocity there is probably better for air/fuel mix. I left the lower LIM alone to avoid any work on the heads. I only polished the runners and reduced the small bump before the injector.

There is only so much power that can be extracted from a n/a intake.

nismology

iTrader: (8)

This might be true if the engine was turning very slowly. But we don't know what the EXACT difference in volumetric efficiency between the banks with the engine in motion at high speeds. Heck, the fact that the elbow that connects the TB to the UIM has difference cross-sectional areas for the top and bottom set of runners tells me that the requirements for both banks are different as far as velocity and volume are concerned. Reminds me of the A32 intake manifolds that are tapered the farther away you got from the TB.

Or maybe equalize airflow? I don't think nissan would purposely get one set of cylinders to make more power than the other @ any RPM. No advantages that I can see.

nismology

iTrader: (8)

I think you're confusing Helmholtz resonance with dynamic supercharging. Very similar concepts except that with dynamic supercharging it's the valve closing that causes the pressure wave to bounce back and help shove more air into the cylinder. Helmholtz deals more with the pressure differentials inside and out of an OPEN air cavity and happens in the intake tract, if anything. But yes, both can increase volumetric efficiencing dramtically if utilized correctly.

Note: I'm no physics expert so I'm not prepared to debate this in-depth. Just observed some fundamental differences between the two phenomena.

madmik

iTrader: (1)

Dynamic supercharging sounds right. Also read that the split plenum we have helps promote all this resonance science and provides more torque. The understanding I have so far about the smaller runners is about creating a different velocity so the powerband range is slightly off from the other bank, giving a wider torque range. From everything I read, removing the VIAS will cause some loss of low end torque due to slower air velocity in the plenum. The smaller elbow opening creates a higher velocity at low speed and stronger torque. At about 4K, the VIAS lets air from the larger elbow opening go to the restricted one. The other piece of science is the divider inside the elbow. Some sort of “RAM” effect also helping torque.

No PHD here either. I used to port my motorcycles but this new science used for the VQ is amazing. Just reporting what I see and understand (or misunderstand).

I polished the trumpets inside the UIM, removed the casting, and polished the runners in about 90 minutes. The EGR pipe protrudes big time inside the UIM runners. I may open up the throat of the runner to compensate. I may obstruct the EGR pipe to send less hot gases (heat) to the UIM.

Just got my phenolic kit today. I can see why some org members hear whistling. It is easy to misalign the LIM spacers because of the inherent space around the bolts and studs. They can move 1/8". I am making sleeves and dowel pins so I get the same spacer alignment when I match the ports as when I install them.

Aaron92SE

iTrader: (128)

I designed the bolt holes slightly bigger than they need to be to help fitment in ALL years of Maximas. In the instructions, it says to apply RTV on both sides of the spacers and firmly press it in place making sure that the ports and bolt holes are properly aligned. Once you do that, it will stay perfectly in place while you install the other manifold. There is no need to make sleeves to compensate for the slack in bolt hole room.

The actual ports in the spacers should be perfectly matched to the stock intake ports. If they aren't please contact me.

The whistling is caused by eliminating the OEM gaskets and not by having misaligned spacers. When you install the spacers, just make sure they are aligned properly when you set them in place with the RTV.

Edit: Also, the UIM spacer shown in your picture is matched to the LIM. You have it placed on the UIM. That is why is seems mismatched. The stock ports on the UIM are smaller than the ports on the LIM. I chose to match it to the LIM since it's better for performance that way.

madmik

iTrader: (1)

Aaron, nothing wrong with the kit.

I am using sleeves for my porting work on the LIM & UIM so the spacer is properly positionned between them. Not for the install. Sorry if I was not clear.

Folks need to pay attention to step 26. They can look inside the LIM to see if part of the spacer is visible. If visible, they need to reposition it. It should not move with the RTV applied but it could.

I would suggest to have a can of Kensington Duster II compressed air on hand. Will get most dirt out if some fall inside the head ports while LIM is off. If you drop a bolt or nut inside, get a flexible magnet rod/pick-up tool to retrieve it.

With deadlines at the office and upcoming time off, this will not get installed before the second half of August.

nismology

iTrader: (8)

Don't mean to sound rude but that makes absolutely no sense to me whatsoever. Never heard of an automaker purposely producing different torque levels between banks/cylinders. And even if this was true, cam angle values would vary between both cylinder banks as well and they don't.

Removing the shelf in the VI effectively shortens the runners and adds plenum volume.

Not quite. Both openings in the elbow are providing air to the motor at all times. I've desribed how the VI works before, but I suppose I'll describe it again briefly.

When the power valve is closed effective runner length runs from the opening in the back of the UIM to the intake ports. This keeps air velocity higher at low engine speeds. When the valve opens up effective runner length is shortened to the individual runners in the UIM and plunum volume is increased as the top and bottom sections of the UIM are sharing airflow, helping top-end breathing.

The FSM has an illustration if you need help visualizing it.


And as for the dynamic supercharging thing, the VQ35 UIM does not support this. There's no resonance chamber in it like with the 00VI/MEVI intake manifolds. Besides, a resonance-tuned IM is tuned for a certain RPM range @ a certain intake valve closings ABDC. Since the VQ35 has continuously variable valve timing on the intake side it would be almost impossible to implement effectively (unless it was a 3-stage system like the 997 GT3's IM, for instance). If the CVTC system was 2-stage discreet it could work easily.