I have an 87 Montero and want to build a Custom Mudder out of it I have heard of a Vortec 4.3 adapter that I can use to slide the 4.3 right into the 5-speed that is in it whichis what I want because of the gearing. The gear box that GM makes is to high end for me I want all low end with a top out of like maybe 85 MPH. I have everything else doe but the 33" tires because a 2.6 just doesn't have the power for that. I also have a line on a blue printed and balanced High Performance 4.3 from a drag car thats back end got crushed by 18 wheels and 20 tons.this engine is pushing 275 horses and would be perfect for my project but I need that adapter <img src="/forums/images/graemlins/kewl.gif" alt="" /> or I need to get a GM 5-speed <img src="/forums/images/graemlins/frown.gif" alt="" />. So if any one can help me out that would be great also I am looking for more lift but as far as I know JCWhitney has a 2" suspension and Rogers has a 2" body lift I have both if anyone knows of anything better and bigger that would be apreciated also. Heres to pipe dreams and building toys <img src="/forums/images/graemlins/cheers.gif" alt="" /> <img src="/forums/images/graemlins/evil.gif" alt="" />

The only commercially available adapter is made by advanced adapters (actually Mark's in aus). This was available for many years (I remember it back when I had my 4banger), but recent inquiries from others point to the fact that it may no longer be available.

In any event, that adapter was for the Buick (Holden) 3.8. Nothing commercially avaialble for the 4.3. THe three here who have done it did so by personally fabricating all aspects of the swap. And they all used GM trannies/tcases. Personally, I think the Mitsu's 1.92:1 is not low enough anyways.

Have you used your rig with the 2.6 much? Tell us about it, and your terrain...

PHIL

Thanks for the heads up on the adapter and thats the first place I looked for it and I tink you may be right about it not being offered as of late.

I haven't done much fourbying other than muddy trails because I have no winch and am afraid I'll get stuck out in the shtick with it. I got it as a daily driver but got sick of the 2.6 it seems gutless to me Z71 thats why I want to put the big engine in it and put some big mudders on it so I feel like I have some thing I can really play with

The stock 5 speed KM135 doesn't hold up to the "power" of even a Ford 2.9l V6. I've owned a Bronco II with the same mitsu trans I currently have in my farm truck. It failed as in broken mainshaft after 30k miles of autobahn driving even with 215/75-15 tires. Not Good. There is a reason that Advance Adapters stopped making the conversion. Most swappers change the trans with the motor. A drag race motor is exactly the WRONG motor you want for oofroad unless you're a competition mudder. You need torque not top end power. The Mitsu gears are about 8.8" and can handle 250 ft/lbs and about 200 HP safely but the trans and TC will be straining with 150 ft/lbs, though they will hold up to Turbocharging. Your cheapest safest upgrade if you keep the stock tranny is to swap in an entire Starion turbo motor, harness and ECU.
For my swap, I'm upgrading to Landcruiser axles, SAS to live behind a mild Mopar 318/727/203/205 combo. Yes , the front diff will be on the opposite side with this. If you want to keep the Mitsu axles, I researched this swap: Cadillac 4.5l V8/ S-10 Blazer trans/ transfer case. This keeps the diffs in the stock location. But, once you put on 35's those mitsu hubs are marginal. It's all about balance and reliability. Sorry if I've burst your bubble but dem's the facts.