Update 6/28/13
Ok I did the swap last night. Just wanted to show more pics and info regarding the before and after of all the parts side by side.
First up the weight of the ported lower vs unported, 5.80lbs vs 6.04lbs. So clearly some weight loss of material.
Next, the openings at the bottom of the runners running in both directions, 1.53" vs 1.43" is where the bump is that the injector is slid into. Clearly with the bump gone its opened up quite a bit!! The other way it not as much opened at 1.99" vs 1.98".
Next, the openings at the top of the lower mani are 1.70" vs 1.70" and 1.53" vs 1.52". The reason the upper part didn't open that much (only 0.01") is because every part on the intake system starts smaller at the TB then gets bigger for the next item. This is because nissan wants the parts to never have to "hit a lip" with air flow. It's better for flow to go through a small space and open into a larger one, than flowing through a bigger opening then hit a lip of metal of the lower mani and cause a bunch of turbulence. So the lower mani's upper part wasn't touched much because the upper mani is what got ported to be port matched to the lower. And looking at the pics with upper mani's gasket system we couldn't port more of it or we'd of ported into the gasket space destroying the upper mani.
Next, 1.86lbs vs 1.92lbs of each TB.
Next, upper mani's weight, 7.90lbs vs 7.16lbs. Now why is the ported mani heavier than the unported? Well the ported one is off a g37. They for some reason give it very long cylinders where the bolts go through adding mass and needing longer bolts. They also use brass vs what looks like titanium on my 13 mani!! All my silver looking threaded parts are rainbow colored like when titanium heats up.
Next, the upper mani runners going in both directions, 1.85" vs 1.82" and 1.56" vs 1.50". Now you'll ask yourself these numbers don't match the numbers above for where it bolts to the lower mani's openings. That's because I didn't measure the exact opening of each item. I stuck my calipers down inside so they laid flat on the parts surface and measured wherever the tips made contact. This just insured a proper measure of each item. The calipers tips are like a 0.5" long so its inside more but i looked and each part is flow matched 100%. You can also see some horrible lips on the unported mani that needed to go away.
Last, the opening of the TB hole on the mani. 2.47" vs 2.46". Again, because of flow its the TB that got all the porting and not the item it sits on. The TB is 100% port matched now to the upper mani.
On a side note. One thing I hate is the oil in the system! I'm not even boosted and oil comes out of the gaskets of the lower mani to head and injector o-rings. Just nasty stuff. I need to have my catch can running to atmos.
Update 3/17/14. Update.
AZ is out. IPS Motorsports in columbus is in. I stopped in the shop and talked to the porter for awhile. His prices seem very low and we can undermine even Z1's manifold with what I believe can be a much better job!
Also I talked to the tuner. We will do everything for you guys! We will dyno my car as is. We will install the lower mani. We dyno again. Then we will tune it. Then we will install the upper mani. We will dyno with the stock tune. Then we will revert back to the lower mani tune and we will tune off that for both mani's. Then do all that with the TB's.
You will know what power you make with each item you buy and add on and you will know the before and after of everything without someone lying and changing dyno numbers. It will be legit, I'll make sure of it as I do all the motor work!
Stay tuned.
Update 3/1/14. I now have a spare mani and lower mani. What I think ill do is just port them for starters. See what the dyno says and then when I get some TB's I'll send those for porting.
Wanted to do another idea I had because I haven't seen it anywhere yet. DEpoint0.5 and I have been talking about porting these items. DE has some TB's ready to do and I just bought the lower intake runners off eBay. I'm waiting to pick up a stock g37 mani off a friend and get some TB's myself so I'm not without a car. The goal obviously is more power. The question is how much power vs what the cost of the porting we be.
Z1 is now porting a stock mani and it's running about $300 plus shipping. The results seem to be you get as much midrange as the motordyne m370 mani (minus 0-3TQ) but you don't lose top end power like you do with the m370. Seems the best of both worlds right?! Well all I've seen is Z1's dyno's with the m370 vs their modded stock mani so it will be interesting to compare the stock mani vs a modded stock mani with my own dyno testing (no cheating
). Then on top of that i will be adding ported TB's and the lower mani since its a crude cast piece that looks very rough to the finish.
Fingers crossed it all works out and its a nice boost for NA power. I'll report back with pics of IPS's work as it progresses.
PS, if it does work out I'll send all 4 of my items to be ported again by IPS and sell them to someone looking for the whole package so your car won't be down. Then you can send your OEM stuff to IPS and the gift keeps on giving.