Mivec Owners Group

It is currently 21 May 2018 08:19

All times are UTC + 12 hours [ DST ]




Post new topic Reply to topic  [ 7 posts ] 
Author Message
PostPosted: 11 Sep 2015 05:27 
Offline

Joined: 11 Sep 2015 04:40
Posts: 4
Location: Denver, Colorado
Country: Denver CO - USA
Hello to all! Found this group quite some time ago but never joined until now. I have been working on this vehicle for a while and have been busy modifying just about every aspect of the vehicle's performance since I originally purchased it. In 2014 I began a big project of converting from the stock 3.0L 6G72 engine to the 3.8L 6G75 MIVEC engine. I have spent a few years doing my research with this engine swap and have recently started finishing 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;
Image

Image
Image


NOW the good stuff 2014-Present
Image


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
Image
Image
Image


Image

Previous methods of this engine swap people were using the 6G75 MIVEC coolant crossover pipe, but this required cutting and welding the pieces to fit and this also placed the distributor 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)
Image
Image
Image


Now for the distributor mounting location in the rear cylinder head to work, it took several months of planning and designing a custom part to make this work. Due to the MIVEC operation, and oiling to the exhaust rocker shaft you simply could not make a spacer plate and stuff the distributor in place. I have produced this plate so that others can also do this engine swap easily. This essentially duplicates the changes Mitsubishi made to these 6G75 MIVEC heads in late 08+ to only use on OCV (Oil Control Vale) 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.

Image

Image


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, but also plan to use the space for an air box for finished intake system).
Image
Image
Image



More updates to 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.

_________________
BlackHeart Motors - Owner
http://www.blackheartmotors.net
2003 Eclipse GT - 3.8L 6G75 MIVEC Swapped


Top
 Profile  
 
PostPosted: 14 Sep 2015 04:15 
Offline
User avatar

Joined: 24 Sep 2008 11:15
Posts: 177
Location: Trinidad,Caribbean
8) 8) 8) Great stuff man. Keep us updated.


Top
 Profile  
 
PostPosted: 15 Sep 2015 00:08 
Offline
Mivec Guru

Joined: 04 Jul 2005 13:25
Posts: 1207
Location: Lower Hutt
Country: NZ
Ideally you'd want to chuck those heads in the junk bin where they belong and fit the DOHC mivec heads from the Diamante 30M.

Also get rid of the distributor and fit wasted spark from the equivalent SOHC Pajero.
Use a GTO (3KGT) computer to control the mivec from the active exhaust.


Just so you know, those heads make 70HP per litre, same as the non mivec 6G72s.
The proper mivec heads make 90HP per litre.
The 6G75 ones are mivec by name only (intake cam only with a bit more lift), they're really for emissions and economy but marketed as mivec and selling on the past performance of earlier mivec models.
Not a lot different from the 4G63 evo mivec which is actually variable valve timing on only the intake cam, still marketed as mivec but it's .......VVT.

OK so you don't get DOHC mivec over there.........we don't get Eclipses here. The steering wheel is on the wrong side.

Anyway, keep up the good work, it'll be interesting to see what it makes on a dyno, see if it'll beat the 3SX N/A ricer build which is still less than a factory Diamante 30M.

Steve

_________________
6G72 mivec Twin TDO5 20Gs up and running.
Scrapheap special making exactly 280 horses at some unknown rpm.
Engine dyno under construction.

It's easier to fool someone than it is to convince someone that they've been fooled.


Top
 Profile  
 
PostPosted: 16 Sep 2015 03:32 
Offline

Joined: 11 Sep 2015 04:40
Posts: 4
Location: Denver, Colorado
Country: Denver CO - USA
morpheus23 wrote:
8) 8) 8) Great stuff man. Keep us updated.

Thank you, I will share some more updates as well

_________________
BlackHeart Motors - Owner
http://www.blackheartmotors.net
2003 Eclipse GT - 3.8L 6G75 MIVEC Swapped


Top
 Profile  
 
PostPosted: 16 Sep 2015 03:45 
Offline

Joined: 11 Sep 2015 04:40
Posts: 4
Location: Denver, Colorado
Country: Denver CO - USA
magn1t wrote:
Ideally you'd want to chuck those heads in the junk bin where they belong and fit the DOHC mivec heads from the Diamante 30M.

Also get rid of the distributor and fit wasted spark from the equivalent SOHC Pajero.
Use a GTO (3KGT) computer to control the mivec from the active exhaust.


Just so you know, those heads make 70HP per litre, same as the non mivec 6G72s.
The proper mivec heads make 90HP per litre.
The 6G75 ones are mivec by name only (intake cam only with a bit more lift), they're really for emissions and economy but marketed as mivec and selling on the past performance of earlier mivec models.
Not a lot different from the 4G63 evo mivec which is actually variable valve timing on only the intake cam, still marketed as mivec but it's .......VVT.

OK so you don't get DOHC mivec over there.........we don't get Eclipses here. The steering wheel is on the wrong side.

Anyway, keep up the good work, it'll be interesting to see what it makes on a dyno, see if it'll beat the 3SX N/A ricer build which is still less than a factory Diamante 30M.

Steve


The main reason I went this route was the original 72 spun a rod bearing, so it was either put a stock motor back in or do something worth while. A few others here in the states have done this swap, but I really did not care for the finished results and how it was done so I took my time figuring all of this out and documenting it for others to make this swap much easier.

There are a few 4th Gen Eclipse owners here as well that are pushing 270+ hp to the wheels with tuning and other bolt-ons so hitting that 3XX hp mark is well within reach, my biggest disadvantage is the elevation where I am (5000+ ft), but I see it as a positive challenge to work with. I am also working on the system which will be using the Q45 90MM TB in place of the sub 70mm throttle body. This one item still stirs the pot with a lot of people, but the dyno results will be proof enough.

The distributor was not my ideal choice for the ignition system either, but getting this swap to be as easy as possible was primary focus. However, I have been working on a COP conversion system for quite some time off and on, biggest requirement was having a running motor to do more of the testing and data acquisition. If you are familiar with the AEM power puck systems for the Hondas, that is essentially what I am developing for the 6G7X series engines so that it can be a "plug and play" type ignition upgrade system.

_________________
BlackHeart Motors - Owner
http://www.blackheartmotors.net
2003 Eclipse GT - 3.8L 6G75 MIVEC Swapped


Top
 Profile  
 
PostPosted: 09 Jan 2016 04:57 
Offline

Joined: 11 Sep 2015 04:40
Posts: 4
Location: Denver, Colorado
Country: Denver CO - USA
Still working on the tuning a little at a time, but here is another video of it running on a cold start up

https://www.youtube.com/embed/rR3pbpVLG80

_________________
BlackHeart Motors - Owner
http://www.blackheartmotors.net
2003 Eclipse GT - 3.8L 6G75 MIVEC Swapped


Top
 Profile  
 
PostPosted: 09 Jan 2016 22:32 
Offline

Joined: 08 Mar 2010 07:31
Posts: 331
Location: Auckland
Country: New Zealand
I love that model eclipse, shame it was never made in RHD for general export

Transplant looks great, i guess it would be as easy for you to get DOHC MIVEC heads over there as it would be to get a 6G75 Mivec engine over here

keep up the good work

_________________
regards

Peter Lee
Broomfish Automotive Parts Specialist
http://www.broomfish.co.nz/shop/


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 7 posts ] 

All times are UTC + 12 hours [ DST ]


Who is online

Users browsing this forum: Google [Bot] and 3 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group