A follow AMC member, jzt, pointed me to this Jap wreck importer in QLD that seems to have a half cut Diamante 30M with a MIVEC 3.0L DOHC 6G72 engine (or maybe just the engine).

It got me wondering and I started searching through the forums for any engine swaps done by any AMC member on 3rd gens (FWD or AWD) but found nothing. I know a few members have done it on the 2nd gens.

My questions are:

1) Is it feasible?
2) Any gains from such a conversion for a 3rd gen AWD?
3) Compared to supercharging or turbos for our SOHC 6G74, would this engine swap be a better deal?

Thanks for any help guys!

A follow AMC member, jzt, pointed me to this Jap wreck importer in QLD that seems to have a half cut Diamante 30M with a MIVEC 3.0L DOHC 6G72 engine (or maybe just the engine).

It got me wondering and I started searching through the forums for any engine swaps done by any AMC member on 3rd gens (FWD or AWD) but found nothing. I know a few members have done it on the 2nd gens.

My questions are:

1) Is it feasible?
2) Any gains from such a conversion for a 3rd gen AWD?
3) Compared to supercharging or turbos for our SOHC 6G74, would this engine swap be a better deal?

Thanks for any help guys!

I'm probably wrong, but i have a feeling the gearbox is on the other side and doesnt line up?

I believe it is a Jap Diamante and the gearbox would be in a similar position to ours?

Mad little engine and engine orientation should be the same after looking over a 30m at a wreckers a while back

A follow AMC member, jzt, pointed me to this Jap wreck importer in QLD that seems to have a half cut Diamante 30M with a MIVEC 3.0L DOHC 6G72 engine (or maybe just the engine).

It got me wondering and I started searching through the forums for any engine swaps done by any AMC member on 3rd gens (FWD or AWD) but found nothing. I know a few members have done it on the 2nd gens.

My questions are:

1) Is it feasible?
2) Any gains from such a conversion for a 3rd gen AWD?
3) Compared to supercharging or turbos for our SOHC 6G74, would this engine swap be a better deal?

Thanks for any help guys!

1) Yes, but like I said, only if you get a halfcut, or else good luck finding the bits you need.
2) Not really any "gains" but your gonna have one very unique car with a very distinct sound.
3) If you have a halfcut, Hell yeah. But FI is totally different to what you want here. You gotta remember a proper FI setup on a 3rd gen (keyword - proper) would set you back $15K......so if you can get the conversion done with standard parts for under $3K your on a winner :D

MIVEC hasnt been done on 2nd gens as the motor sits the other way around;) Also noticed on an FTO MIVEC at the wreckers they have an IAT at the back of the intake manifold where the VICS motor is, can anyone confirm its an IAT?

;1205185']1) Yes, but like I said, only if you get a halfcut, or else good luck finding the bits you need.
2) Not really any "gains" but your gonna have one very unique car with a very distinct sound.
3) If you have a halfcut, Hell yeah. But FI is totally different to what you want here. You gotta remember a proper FI setup on a 3rd gen (keyword - proper) would set you back $15K......so if you can get the conversion done with standard parts for under $3K your on a winner :D

MIVEC hasnt been done on 2nd gens as the motor sits the other way around;) Also noticed on an FTO MIVEC at the wreckers they have an IAT at the back of the intake manifold where the VICS motor is, can anyone confirm its an IAT?

Yeah I agree with what you said in the PM too Tufftr. It's a good try if i can get a halfcut, else not a good idea i reckon. The only gains i can think of is the slight power increase to 199kW at 7000rpm but slight loss of torque as compared to the 3.5L 6G74.

However, if it can be done under $3k we indeed have a winner don't we? :D

Yeah I agree with what you said in the PM too Tufftr. It's a good try if i can get a halfcut, else not a good idea i reckon. The only gains i can think of is the slight power increase to 199kW at 7000rpm but slight loss of torque as compared to the 3.5L 6G74.

However, if it can be done under $3k we indeed have a winner don't we? :D

I would think that torque in the AWD would be the last thing you'd want to be losing & the absolute first thing you'd be looking at improving with any modification. How much loss are you talking about?

There is no loss of torque with the 30M, only a GAIN!

Yeah I agree with what you said in the PM too Tufftr. It's a good try if i can get a halfcut, else not a good idea i reckon. The only gains i can think of is the slight power increase to 199kW at 7000rpm but slight loss of torque as compared to the 3.5L 6G74.

However, if it can be done under $3k we indeed have a winner don't we? :D


There is no loss of torque with the 30M, only a GAIN!

Well someone's incorrect here, then?

I don't know who's right or wrong, but I'd like to know if there's a gain/ loss & by how much.

MIVEC DOHC 3L 6G72 = 199kw @ 7,000rpm, 301nm @ 4,500rpm.

Non MIVEC SOHC 3.5L 6G74 = 153kw @ 5,000rpm, 313nm @ 4,000rpm.

Oops, my bad. Just double checked, apparently Non MIVEC SOHC 3.5L is slightly torquier than the Mivec 3L...

The power delivery is quite different and will feel like a completely different beast, very revvy and ultimately more performance on paper. Real world difference would be much closer though. Sohc still makes more torque down low. Would be interested in seeing the mivecs power and torque delivery graph

Just found this thread and had to comment as ive owned a 3.5l sohc and now have the 3l mivec. the difference in performance is huge!, the 30M is a much quicker car, especially using tiptronic and keeping it over 3000rpm. as well as mivec the 3l engine also has variable intake lenth setup, i dont notice any difference in low down torque performance, ie around town etc. id love to see someone do the conversion.

You dont want to have a revvy enging in an AWD magna, you want something that gives you a load or torque at the bottom end, not up at 4500rpm, you can not get the AWD off the line well enough if you need to rev the ring out of it to get up and going

You dont want to have a revvy enging in an AWD magna, you want something that gives you a load or torque at the bottom end, not up at 4500rpm, you can not get the AWD off the line well enough if you need to rev the ring out of it to get up and going

With Mal on this one, definately not an engine for the AWD (unless you build a hybrid engine with larger displacement). The engine is more suited to a Manual FWD to be able to use it properly. However I know of one member looking into this at the moment, and the half-cut alone is $4000.

you dont have to rev the ring out of it to get going, thats the thing, remember even before you hit mivec its still as powerfull as a DOHC 6g72 V6. theres is loads of torque. but id say for the 4wd, the 6g75 would be a better bet, although there is alot of fun to be had at 7000rpm!

Thing is, only real upside is having the two camshaft profiles. one for down low (good idle quality, good low down torque) and one for up high (huge high RPM power etc) but I mean with the money you'd spend otherwise on the MIVEC your SOHC 24v could be a happy little revver aswell. Full exhaust, some basic ported heads and 280 cam's with a tune - would be heaps of fun and see you well over 7500RPM.

;1353032']Thing is, only real upside is having the two camshaft profiles. one for down low (good idle quality, good low down torque) and one for up high (huge high RPM power etc) but I mean with the money you'd spend otherwise on the MIVEC your SOHC 24v could be a happy little revver aswell. Full exhaust, some basic ported heads and 280 cam's with a tune - would be heaps of fun and see you well over 7500RPM.

What, like 380 cams but with .100" less lift and/or 100 degrees less duration? /sarc

What, like 380 cams but with .100" less lift and/or 100 degrees less duration? /sarc

Ahh.....I got that joke....not bad not bad......4/10 for that one.
But yes - nothing wrong with the 74' SOHC....just need to spend money in the right areas.

Any setup from before mid-2000 to be transplanted into an AWD would require some ingenuity with regard to the ECU, as they would be the old 16bit ECUs and don't couple with a BEM. I came across a reference to there being a 6G75 GDI version of the JDM Diamante in about 1998-99 - quoted figures were about same power and slightly more torque than a 6G75, and peak torque was down around 3500rpm. so even more attractive for an AWD than the 6G75.

I haven't chased up whether the reference I found was accurate, though I do know the 6G74 GDIs were sold in Pajeros with slightly different tuning (though not here, probably because we didn't have low sulphur petrol at that time). At the very least, I would love to lay hands on a GDI ECU (Diamante or Pajero) to peek at the code...

WytWun (http://www.aussiemagna.com/forums/member.php?u=21170), don't bet on that. The JDM Diamante's were about 5 years ahead of the Australian ones. The blackout cluster for example was standard in the 1995 Diamante 30M, but didn't surface in the ADM Verada until 1999.

You wouldn't run the stock ECU anyway. Full aftermarket with MIVEC support would be more suited, would also allow a MAF delete.

WytWun (http://www.aussiemagna.com/forums/member.php?u=21170), don't bet on that. The JDM Diamante's were about 5 years ahead of the Australian ones. The blackout cluster for example was standard in the 1995 Diamante 30M, but didn't surface in the ADM Verada until 1999.

You wouldn't run the stock ECU anyway. Full aftermarket with MIVEC support would be more suited, would also allow a MAF delete.


The 32bit CPUs used in Mitusubishi ECUs only went into production in mid 1999, so I'm pretty sure any Mitsu cars, JDM or otherwise, produced before 2000 had the older 16bit ECUs.

As far as I've yet been able to find, going with a MAP rather than the MAF isn't much of a gain without boost. The restriction imposed by the MAF is only a very small part of the overall induction "loss".

Enough is now known about the Mitsu ECUs, 32bit especially but even the 16bit, that I wouldn't go with an aftermarket ECU. But then I'm a software person who'd rather fiddle with code than try and configure someone else's black box with lousy documentation.

The 32bit CPUs used in Mitusubishi ECUs only went into production in mid 1999, so I'm pretty sure any Mitsu cars, JDM or otherwise, produced before 2000 had the older 16bit ECUs.

As far as I've yet been able to find, going with a MAP rather than the MAF isn't much of a gain without boost. The restriction imposed by the MAF is only a very small part of the overall induction "loss".

Enough is now known about the Mitsu ECUs, 32bit especially but even the 16bit, that I wouldn't go with an aftermarket ECU. But then I'm a software person who'd rather fiddle with code than try and configure someone else's black box with lousy documentation.

There isn't much choice with the 30M ECU, it faults without the other systems in place (ie. 4WS), is only compatible with the JDM "180" cluster, and the standard Magna ECU will not have parameters for MIVEC. Another thing to note is with an aftermarket you can control when MIVEC kicks in (ie. kick in sooner).

Not much is known about the Mits ECU's at all, there are 2 people I know of in Australia who can tune a TJ onwards ONLY ECU. One is in Adelaide, the other in Sydney. And they can only tune Magna and Evo maps. Diamante is a completely different kettle of fish.

The successful 30M conversions have all used aftermarket ECU's with excellent results (these were mostly Mitsubishi GTO's - see 3si).

46kw gain trumps 12nm loss. As if you'd even notice 12nm? You would certainly notice 46kw. Thats like sticking a Daihatsu Copen under the bonnet

46kw gain trumps 12nm loss. As if you'd even notice 12nm? You would certainly notice 46kw. Thats like sticking a Daihatsu Copen under the bonnet

6G74/2-30M Hybrid ftmfw! No change of engine number required. Just needs oversize (10:1) pistons

46kw gain trumps 12nm loss. As if you'd even notice 12nm? You would certainly notice 46kw. Thats like sticking a Daihatsu Copen under the bonnet

you have ignored the fact that the torque peak is also 500rpm higher in the rev range, this makes the loss of low range torque even more apparent

you have ignored the fact that the torque peak is also 500rpm higher in the rev range, this makes the loss of low range torque even more apparent

Yeah but when your foot is flat to the floor to feel the GGGGGEEEEEEESSSSS your not gonna care about a bit of torque lost down lower in the RPM band.

If all you want in your car is a low down torquey cruiser, 3.5L SOHC is fine, I guarantee anyone thinking of doing this conversion is so they can go balls out all day long and enjoy that upper RPM grunt.
Life - pretty sure the MIVEC has 10:1's already? (correct me I'm wrong danielson)

Wytwut - MAP sensor isn't there for a gain - but it makes overall tuning 10x easier when all you need to deal with is kpa rather then the frequency of the MAF and tricking it.
With my ECU if all I had was a base map, All I'd need to do is whack it on rapid tune mode and go for a 2 hours drive, it'll have a tune at about 90% of what a dyno tuner could do. MAP sensor rules here.

There isn't much choice with the 30M ECU, it faults without the other systems in place (ie. 4WS), is only compatible with the JDM "180" cluster, and the standard Magna ECU will not have parameters for MIVEC. Another thing to note is with an aftermarket you can control when MIVEC kicks in (ie. kick in sooner).

If you were expecting plug'n'play, then I can understand your negativity.


Not much is known about the Mits ECU's at all, there are 2 people I know of in Australia who can tune a TJ onwards ONLY ECU. One is in Adelaide, the other in Sydney. And they can only tune Magna and Evo maps. Diamante is a completely different kettle of fish.

There might only be two people doing it commercially, but that doesn't mean it can't be (or isn't being) done. I personally have been in contact with two people who are tuning their own cars, and could tune my own if I knew anything about tuning. And its not just Evos & Magnas....


The successful 30M conversions have all used aftermarket ECU's with excellent results (these were mostly Mitsubishi GTO's - see 3si).

That may be the most expedient way for people who aren't into the software aspect, which I can well understand. But that doesn't mean it can't be done, and done well, without resorting to commercial solutions.

;1354161']Wytwut - MAP sensor isn't there for a gain - but it makes overall tuning 10x easier when all you need to deal with is kpa rather then the frequency of the MAF and tricking it.
With my ECU if all I had was a base map, All I'd need to do is whack it on rapid tune mode and go for a 2 hours drive, it'll have a tune at about 90% of what a dyno tuner could do. MAP sensor rules here.

If you use the native ECU, you're working with the MAF rather than against it. If you've looked at some Mitsu ROMs with ECUFlash, the "Load" axis on the fuel and ignition maps wraps the MAF up nicely so you don't have to deal with MAF frequency until you operate the MAF outside its design parameters.

There are definitely reasons to prefer a MAP with a highly boosted engine, but some fairly potent Evos have been tuned with the stock MAF without undue drama.

And auto-tuning, as per your Adaptronic, is not exclusively related to use of a MAP. Fundamentally, the MAP and MAF are just different ways to infer the same quantity. Their operational differences are just implementation details which need to be handled differently at the software level.

you have ignored the fact that the torque peak is also 500rpm higher in the rev range, this makes the loss of low range torque even more apparent

But seriously, 500rpm when you have a revvy motor takes less than point beezdik of a second. If we were comparing 400nm @ 2500rpm to 300nm @ 6000 rpm there would be a noticeable difference. Either way, changing from an engine with ~150kw that breathes like an asthmatic at 5500, to something with almost 200kw that's happy to breathe right up to 7000 and beyond would be very noticeable.

4% torque loss and 30% kw gain.

Im with you Feeeky , the power increase is awesome. The mivec doesnt have an AFM in the intake pipe, has a sensor in the firewall connected to a vaccuum tube on the manifold. also there is no point to altering the mivec changeover point, unless you change the cams for aftermarket ones. mitsi have tuned the point to when the smaller lobes lose power and the larger lobes are in range. any change will lose torque and power. its a mistake many mirage owners over here make, and the guys on mivecowners group say the same thing. I do not notice any loss of lowdown torque over the 3.5l i had, i do notice the ability of the mivec to rev freely and it pulls hard right to 8000rpm, the 3.5l i had died at 5000rpm. when i removed the cat converter the mivec responded well.

I have done 2 mivec 6g72 conversions into late model magnas. It will bolt up to the awd trans no worries. the awd eng/trans ecu is the problem in the later model magnas. The earlier te/tf/th with seperate ecu's are no worries, just change the engine ecu and do a bit of wiring. If keeping auto, I would recommend using the MIVEC F5A51 auto trans as it has factory lsd and massive driveshafts. The mivec throttle body is larger from factory than I have seen any others machined out to. I have found them very easy to drive, but when up in the rev range it is VERY responsive. I have a genuine MMC engine manual for the 6G72 MIVEC engine as well. All specs are available. They happily take a massive amount of abuse. As Robssei says, they pull very hard to 8000 rpm. Put it in drive and put your foot flat, it will do a smoothe gear change around 7500rpm. Put it in tiptronic and you can hold it to the rev limiter.

I do have access to a complete 3.0 diamante awd mivec front cut. This, like my 2.5 is still able to be started in the front cut and would be a great set up.

Only concern is that with the power being higher up will this suit an already lacking awd auto

I suppose if you are looking for a good launch, then more cubes the better. If you are looking to play while the car is already moving, then go for more horsepower and drop it back a few gears. If you can get horsepower and torque, all the better. I don't know if there is an affordable compromise to this.

i believe it would be an awesome project and gains would be noticible, the mivec engine is just so much fun to drive, and the baseline engine package suits tuning i belive, DOHC, MAP, COP setup. I know from experience they take alot of hard running, and the whole mivec system is actually very simple and reliable. someone do it!!!!!!

The compromise between high rpm power and good launch is to give it heaps of gas and slip the clutch or get a stupidly high RPM lock-up on the torque converter. :)

I'd love to see a proper power & torque curve from both engines - I think it might surpass a 3.5L V6 at anything over 1500rpm and probably equal it below that.
But that's just my ignorant guess. Is it worth trying to find this sort of info?
From memory the Mivec 3.0 is 199kW, isn't it? I spend enough time over 3,000rpm that this would be good for me :)

i owned the 3.5l sohc and my 30M definitely beats it over the entire rpm range, although it was a 4 speed auto as opposed to the 5 speed tippy in the 30M, but the power increase is enough for me to know that the gearbox is not the main reason for the power difference.

I have a MIVEC engine sitting there being useless. I was hoping to do the conversion. My worry is that
1) Will I need to change engine mounts?
2) I will need to buy a very good ECU with MIVEC capability, sequential ignition as I'm pretty sure the 6G72MIVEC runs coil packs
3) What will happen when I decide to put forced induction on it in due time? After all it will need a whole engine build.

mounts are slightly different as the multilink suspension on the Diamante has a different strut tower shape. you will have to have the Mivec 30M ECU or an aftermarket one with mivec capability. They run coil on plug system, three on front bank and three leads to rear bank. The compression ratio is 10:1 so needs 95 octane + , and would be ok low boost i think.

I have ECU for engine, ECU for the box, loom, engine and box. AdelaideJap swore that the engine was running prior to shipping it to me but during transportation 2 sensors (throttle body position sensor and the one opposite it on the throttle body) were broken. Engine has stuff hanging off it, has exhaust manifolds still on. Even brackets that attach to mounting on the car are still on.

i thinks with what you have there it would be a relativly strait forward swap. i had a direct comparo today with a 3.5l sohc diamante and beat him easily, strait off the line i was a car lenth ahead, hit mivec and gone, once you are up over 5000rpm, if you change on redline, 2nd and 3rd are still in mivec territory, 4th and 5th are just under.

Max,
There is an option of dropping your easy to transport parts up here for me to look at, I may be able then to get an idea of how easy or hard this would be, and then once we can get an idea, perhaps use one of the front cut wrecks I have here as a dummy fit to we can then see if we can get this to run, if so then is a matter of simply putting into your car.

Main issue will be trans as we will need to use your trans, unless of course this manual conversion I am working on works and then we just do it MIVEC with Manual

Back in the day RPW did a 30M Manual conversion on somebodies Magna. I forgot their username but there was a post on AMC. Apparently some machining was required in order to fit the MT on the 30M engine.

Another possibility is to do what the 3si guys have been doing for years. Fit the 30M Heads on to the 3.5 block (resulting in 3.5L MIVEC) - For best results pajaro pistons should be used. Of course cost is higher, however change of engine number etc... is not required with the authorities and numbers will still be matching.

As for controlling MIVEC switchover, some piggybacks support this - same goes for COP.

Yeah but was that Magna an AWD model?