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Discussion Starter · #1 ·
Figured it has been a long time so I would put together a quick project thread over here. I have been getting asked about this by so many people and have been getting tons of positive feedback about it.

In 2014 I began the big project of converting from the stock 3.0L 6G72 engine to the 3.8L 6G75 MIVEC engine. I have spent quite a few years doing my research with this engine swap and have started finishing up this conversion. I will try to share as much information as I can, but if you have any questions please do not hesitate to ask!

From the beginning 2012-2014;




NOW the good stuff 2014-Present - MIVEC Swap Begins

First draft of the 6G75 MIVEC Swap list can be found on the Tech page here;
BlackHeart Motors - Tech

Required parts list -
6G74 Lower Intake Manifold – Gasket match lower flange to MIVEC gasket
6G74 Fuel Rails & 6G72/4 Fuel pressure regulator
6G72 Crankshaft Position Sensor w/Reluctor wheel
6G72 Distributor & BHM Distributor Mounting Plate
6G74 Power Steering bracket
6G74 Lower Timing Belt Cover
6G74 Alternator Bracket
6G72 A/C Compressor bracket
6G74 Coolant Housing & Sensors
6G72 Side Engine Mount bracket
MIVEC Patched ECU/PCM File or Separate MIVEC Controller






Port shaping 6G74 Lower intake manifold (we used this to be able to mount the return style fuel rails easily) The 6G74 and 6G75 MIVEC port shape at upper flange is identical, so only changes needed is a MIVEC gasket match to mate with the MIVEC cylinder head. More information of the MIVEC gasket matching can be found here; BlackHeart Motors - MIVEC Port Matching





Previous methods of this engine swap people were using the 6G75 MIVEC coolant crossover pipe. Doing this required cutting and welding the pieces to fit, and this required the distributor to be mounted in the front cylinder head versus the rear like OEM placement of the original engine (and 6G74 engine). Here you can see the Diamante 6G74 coolant crossover pipe assembly fitted and still allowing space for the distributor in the rear cylinder head (more detail on this below)

 

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Discussion Starter · #2 ·
Now for the distributor mounting location in the rear cylinder head to work, it took several months of designing a custom part. Due to MIVEC operation and oiling to the exhaust rocker shaft you simply could not make a spacer plate and stuff the distributor in place. This essentially duplicates the changes Mitsubishi made to these 6G75 MIVEC heads in late 08+ to only use one OCV (Oil Control Valve) to operate MIVEC functions in both cylinder heads. An oil supply line comes off the front OCV and feeds into the supply port in this plate.

I produce and sell this plate as a kit so that others can do this engine swap easily, those of you who were at Factory MOD 2015 this last summer may have seen the display stand of this part on a customer's 4.0L MIVEC swapped Eclipse (article here BlackHeart Motors - The Flyby).






Here I am starting to get the engine harness sorted out and cleaned up. The fuse box has been removed from the engine bay and placed to the rear of the vehicle along with the battery (cosmetic preference).





Now because I opted to use a modified 6G74 lower intake manifold, I was not able to use the 6G75 MIVEC upper intake manifold (flanges are different size between the 6G72/74/75 Non-MIVEC and MIVEC). This conversion still had to pass emissions testing as well so I am simply modifying the 6G75 MIVEC intake plenum to work with the Kia Sedona intake runners. This was done to retain EGR provisions on the plenum itself, and this will also increase plenum volume.






More updates will come, but this should be a good start on the project for you all to check out. For those that are curious about MIVEC control, it is being done via the OEM 3G ECU with a file made specifically for this (something I started working on back in 2012 actually). It will retain OEM function (duty cycle based) rather than just an "on-off" switch like others have done
 

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Discussion Starter · #4 ·
One hell of an overhaul man! Looks great! Have you been able to line up with a 4G GT in a 1/4 mile or anything? Curious to see how much the differences in tranny, weight, drag, etc. come into play!
I am still finishing this thing up so I have not had a chance to really run it along side anything, but I certainly plan to find out how well it does.

On paper this is the information I can offer (realistically anyways). The swap itself in a very conservative figure is about a 70HP increase from stock, but we all can agree it is certainly more than that.

Stock weight is 3142 so I will use this figured;

Stock 6G72 HP call it 195
Stock Power to Weight of .062

Stock MIVEC HP call is 265
MIVEC Swapped Power to Weight of .084

Keep in mind this is all just "theory," but I am not shooting for any HP records either, just something with more power and enjoyment to drive. Top end is all stock with the intake system the one exception (stock heads, short block...blah blah).
 

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Discussion Starter · #7 ·
Beautiful build, keep it going!
Nice, nice build!!
Thanks guys!


These are the new "2016 model" distributor adapter plates. I worked on the design more for the cosmetics of the plate, logo is no longer covered upon installation, and the final product is even better than before :ndance:


 

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Discussion Starter · #8 ·
Last week I took some time off and spent a couple days finishing the modified 6G75 Non-MIVEC intake manifold. This has the EGR pipe flange removed, and the exhaust passage in the casting milled off. I cleaned the surface up to a light polish and then placed some DEI Cool Tape on the under side as some heat shielding.

I also modified the stock 72 Throttle body, cleaned up and mounted to the manifold. Yeah, some will question why the 72 TB, not a big deal. It's just to get running for the moment and I don't have to mess with this flange transplant and crap. I have a Q45 throttle body to replace it anyways.

I need to notch the hood brace and install this, then will be doing a quick fire up here shortly







 

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Discussion Starter · #9 · (Edited)
Fired up the motor on the 31st,
https://www.youtube.com/watch?v=-NSjmrhjFcU&feature=youtu.be


Here are some pictures from last week working on the car too.

These are a set of long tube headers from Bj (boostezealot) I needed to remove one of my cooling fans since it hit the header so I need to find some new ones...again lol....damn.



I need to get these installed yet too



Still working on the tuning stuff, but flashed a new ROM this morning and the car idles better than it did when I began a little tuning on Saturday.
 

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Discussion Starter · #12 ·
Sounds mean man! Keep it up!
Thanks man!


I still had to extend the driver side headlight, fog light, parking light, and cooling fan wiring from the fuse box in the hatch up to the front accordingly. While doing this I cleaned up the routing a bit more and made progress down into the spare tire well. I still need to work out the mounting specifics in here, but I want it to be fairly clean when you lift the cover.










With the cooling fan wiring up to the front I also needed to replace the fan on the driver side of the radiator. The motor no longer worked so I just installed the Derale fan that was on the passenger side. I believe I will add a pusher fan to the passenger side for the additional cooling. When the time comes to replace the radiator with a new one I will do two pusher fans on that change over.
 

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Discussion Starter · #14 ·
Slacking on updates here, long story short the motor spun a rod bearing on #3 which was my own fault for not tearing into the motor a bit more before the swap. Heavy oil sludge build up in the motor and it was having issues cranking over within the first day of firing up the motor, it just became worse until it just locked up the crankshaft within a couple days of running it. The tuning was never an issue as ignition timing was quite conservative and I never had any knock counts higher than 2-3. The engine was simply just poorly maintained;


Went through the motor, new crankshaft, bearings, piston rings etc...just a quick overhaul of the engine. Building the motor just was not in the plans for me right now as the MIVEC swap is already a respectable bump in power from the stock 3.0 so I wanted to just drive this thing a bit and enjoy it.

I have the engine just about ready to go, should be able to fire up this week I think


I also picked up the newest addition to the intake system this weekend and will begin testing and flow documentation in the coming weeks. More information can be read here
BHM MAF Adapter -





 

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Quarter of the way through I realized this is not exactly what I was looking for BUT man… I was so impressed with your work I read it all, in awe tbh. Good job man!
 
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