I'll explain more later, but I thought for now it would be good to at least post some pics of the G4JS intake.

 

You definitely like to tinker!

 

Yea, in the middle of restoring my 240Z, which is the first time I've done metal work on a car. Since I'm currently building a forged engine for the GTR, it's getting my OEM engine mated with a 7speed DCT trans from a BMW M6. My buddies shop is currently making the adapter.

 

BTW, I only did this because my fuel supply line rubbed a hole in my AC suction hardline and it started leaking. Damn hose is on national back order from Japan!

 

You can get the AC hose remade. At least thats how my friend fixed his damaged AC line. Just went to the local hose supply and they made him a new hose.

 

I'm probably just going to TIG weld a patch since it's aluminum. It's the larger hardline that attaches to the firewall so unsure if it can be remade locally. I'll snap a picture later and post.

 

This coupled with a large plenum (~4 litres) would make for great power with low end torque!

 

I'm going to keep it around 2L or so, which is substantially larger than the OEM plenum i've been running. Don't care about peak number so area under the curve is more important.

 

Fair enough!

Do Hyundai have any engine variants that came out with multi intake runner paths? (Short + long via valves)

 

I'm not aware of anything like that, but I've not specifically looked.

 

I was able to fix the AC hardline by ordering a small Tungsten electrode and just welding the hole. I pressure tested the line up to 90psi and then pulled vacuum on the AC System and it held after 45 minutes so all is good and a $20 fix.






The next order of business was to start mocking up the new plenum to see what was possible. I think the basic shape is done, but I'm gonna have the shorten the plenum on the TB side because otherwise I won't have enough room to make the 90deg turn off the TB to the upper intercooler pipe. Looks like about another 1/2" might do the trick. Should have it all the way mocked up tomorrow minus the TB flange since I need to make one out of 1/2" aluminum. Plenun is 3.5" wide and tapers from 4" tall to 3" tall from front to back and made of 0.188" T6061.

 

With all that I've seen you can do, I am surprised you didn't cast your own from scratch lol.

I've wondered what the long runners would do for for the set up I am helping a buddy work on. Nonetheless, great thinking looking forward to your results!

I have to ask is there anything about the factory js IM that would prevent it from being swapped directly into where an oem one sits ?

 

There is a tab on the end of the head flange located on the passenger side that you have to grind off, which then allows it to properly bolt to the head. The runner openings and alignment are an exact match to the OEM manifold and gasket. As shown below, in factory form the IM will hit the center mount for the strut bar. You either remove that mount off the firewall or fabricate a new plenum. That simply addresses getting it bolted to the head and not the other mods required.

 

progress, but still have to make the TB flange out of 1/2" thick 6061 and shorter the plenum by ~0.75". I also need to add additional vacuum provisions for the brake booster and BOV, install the MAPS sensor flange, and weld on the TB linkage mount. When that's done I then need to somehow pressurize to about 50psi and submerge in my utility sink.

 

I had to send out the TB flange and the TB for some machining. I had the TB flange cut to match the plenum dimensions for welding purposes. I also had the TB machined where the TPS sensor mounts, which I was able to remove ~0.125" to gain space from the firewall. I have to weld on the throttle cable bracket and a few more vacuum line fittings, but should have it running soon.