Hello all, my name is Matt. I'm new to the forum but not new to Mitsubishi. I've been working on 6G72 and 6G74 performance engines for over 12 years. I'm an ASE certified mechanic and AEM factory trained tuner. I've spent 1000's of hours on the dyno tuning these engines. I've owned and worked on 100's of twin turbo 3000GT and Stealth vehicles many between 500-900HP.

Anyways, I thought I needed to share that info before I asked my question and told everyone my new project. I figure that may minimize the "you can't do that" or "that is too hard" or "this kid is retarded" comments.

I bought a 1990 Montero for a DD beater and absolutely love it! The only thing is that it is lacking some major power. Not a big deal, nothing a couple turbos can't fix. I just need your help getting to know the platform a little better.

Here is my initial idea:
3.5L motor out of a newer Montero
stock 3000GT twin turbo parts
3000GT ECU and wiring harness with integrated montero TCU

I've done this a few times in other vehicles and it works great for about 10psi around 275WHP. The larger displacement mated with the small vr4 turbos gives instant spool around 1500rmp. Perfect for a DD and to ward off those pesky Diesels.

Another option would be to run a complete longblock from a vr4. This has a lower compression ratio and would allow for more boost and ultimately more HP but it would be from a transverse mounted car and the upper plenums would give me issues.

Here are my questions to yall:

1. Has anyone done this yet?
2. Has anyone done a SOHC 3.0 to DOHC 3.5 swap in a Gen1?

Here are my potential issues:

1. Oil pan clearance with the front axle (4x4)
2. turbo clearance using the stock vr4 exhaust manifolds

If the 3.5L will fit in there without two much issue, then that will be the way to go. What years did the Montero come with a DOHC 3.5L?

This is a long term project, so you will not see any results soon. However when I set out to do something, it gets done! So please don't think this is some kind of pipe dream.

Thanks for all your help.

Ohhh, sweet.

My '95 SR came with the DOHC 3.5, but my knowledge is limited. Others will chime in here shortly, I'll bet.

I believe the fairly tight space considerations will be the biggest concern...

Good luck and good shooting!

John B.

Thanks! You have a nice looking Monty! When may current tires wear out I want to lift it and get some 33's like yours. What lift do you have? 2" is good for 33's?

Here is a pic of my beast

With the Gen I LWB, 33's require a 2" longer coil spring (or spring spacers) and a cranked torsion bars. Oh, you'll need to trim the rubber from the bumper ends on the stock bumper.

As for a Twin Turbo v6 Monty, my mind is quite hazy on this (normally is anyway) but someone has probably done it. I know for sure others have put in the 4.3L Chevy V6 (too many to keep track of now), Mitsu v6 w/ Supercharger (FrankR), etc.

Others have done the Starion Turbo to the 2.6L I4 engine with good results too.

I've got a Twin Turbo 2.7 in mine & the traction is awesome... (Audi S4, not Montero) <img src="/forums/images/graemlins/wink.gif" alt="" /> <img src="/forums/images/graemlins/lol.gif" alt="" />

Anyhow, I'm looking forward to seeing what you decide to do and watching the execution. <img src="/forums/images/graemlins/kewl.gif" alt="" /> <img src="/forums/images/graemlins/cheers.gif" alt="" />

MBrannon, the avatar picture isn't even my truck. Mine are in my signature, but the picture is a 1990-ish 4-door on 33x12.5/15 tires with a 2" body lift and cranked torsion bars in the front. It belongs to a guy called BottomFeeder, who we don't hear much from anymore, since he moved to the flatlands of Oklahoma City.

Not a very exciting platform in stock condition...until you see where it can go, and get home from.

John B.

uhh to get a little bit back on topic..

I have not seen a twin turbo swapped in yet, but would love to see it done.

The Russians installed what looked like a N/A 6G74 DOHC into a Gen1 so it looks to fit.

Also the AZ crew had one in place on a project that never got finished.

Also Old cold from this board installed 3.5 DOHC heads onto a 3.8 block in his 95SR..So thats someting to consider if you want to max out the platform this is something to look at.

the 3.5 was introduced into the Montero in 94

it was DOHC from 94-96

in 97 the 3.5 SOHC was the only engine used up until 03 when the 3.8 SOHC replaced that...HTH

IMO your biggest concerns will be figuring out/fabrication of the turbo exhast manifolds and plumbing. Doing a 2" body lift may help out a bit with the fender well and under hood clearance issues. Good luck and cant wait to see what you come up with.

Enjoy

http://wrenchmonkey.com/Webpages/6G74swap.html

I would rather let fire ants eat my eyeballs out than do all that crap!?!?!?

Hats off to whoever figured all that stuff out!!!<img src="/forums/images/graemlins/kewl.gif" alt="" /> <img src="/forums/images/graemlins/kewl.gif" alt="" /> <img src="/forums/images/graemlins/kewl.gif" alt="" /> It SURE as heck wouldnt have been me! <img src="/forums/images/graemlins/barf.gif" alt="" />

Welcome, Matt,



Use a Montero 3.0L 24v DOHC plenum if you're concerned about the thermostat housing location.



No - not that I know about.



No, but OldColt (Charlie) has installed a 3.8L with reworked 3.0L DOHC heads in a Gen2.



Both are legitimate concerns, but there's likely a way around if you want to do it badly enough.

Here's my solution to the power question, but it's still evolving:



If the parts ever present themselves to me at a reasonable price, the next one might be a 3.5L block stroked with a 3.8L crankshaft and a blower.

Good luck and post some pictures of your progress.

Frank

This has been discussed in the past as well. Do a search for users VR4 and Hans_GZP, and FrankR as well. IIRC, the biggest challenge ends up being that the 3000 TT exhaust manis won't fit/work in the long mounted engine bay.

Oh, welcome to the wire. Sounds like you'll be a fun one to follow threads on... <img src="/forums/images/graemlins/cheers.gif" alt="" />