Need some advice & info! My son & I are working on an SWB 89 Montero with a 3.0 V6 in it. I bought this girl cheap with a supposedly blown head gasket. Thought it would make a good starter 4X4 for my 16 year old son. I my self own jeeps, but decided a small SUV would be better for his first car. Well the blown head gasket ended up being an upper plenium gasket which would have been great except, the previous owner had let this unit sit for a couple of years with the coolant in the pistons and oil pan. Due to the fact that I have been a heavy equipment mechanic for more years than I care to count, I thought "No big deal, this is a prime bonding opportunity with said son". Well several hundred dollars later, I'm thinking of bonding this thing out the door!
Now that I've vented, let's get to the subject at hand.

First of all we completely tore down the engine, had the cylinders bored .045" (to get rid of water pits & etching - Told son "For bragging rights and mass power")had heads re-done and ported, new pistons, had injectors cleaned, and all the other misc. should do's: water pump,oil pump, timing belt & tensioner, etc. Put her all back together and got her running. We set the base timing at 5*BTDC as per the FSM we downloaded from the website mentioned in an earlier forum (Thankyou to whomever made that available)Set TPS, SAS, and everything else we could find. Now for the question!

1) The monty starts great (acts a little cold natured-rough idle and such for first 3-4 minutes)but had NO power. We put in a new fuel pump,& filter and tapped into the fuel pressure line. We found the fuel pressure at an idle with the regulator vacuum hose connected to be 43psi (Spec is 38) with the regulator vacuum hose disconnected it was 50psi (Spec is 47-53). One thing we noticed is that with the regulator vacuum hose disconnected the idle smoothed out and the engine no load reving was alot crisper. When the hose is connected the idle rpm drops and bounces, and the no load rev is sluggish. Suspect the regulator may need to be replaced but the results of the pressure test don't make sense to me.Could we be over fueling at an idle? (43psi) if so why does it run better at 50psi?

2) At a base timing of 5* to 7* BTDC the dude falls on it's face at low end and has no power. (I don't normally like to set up engines by ear but after explaining to my son that you should alway's use a meter or gage so you know where you are at) I started cranking the distributor a little at a time to make her fire a little sooner. Low and behold we started seeing some results, we got her set where she performs pretty decent but she still is not very peppy. We checked base timing again and found that we now have it set at 16*BTDC. Seems like a lot but that's where it runs best. When we remove the ground and check the timing she's off the little scale, and we are almost at the end of the adjustment slot on the distributor. Any suggestions or is this common with this engine.

3) Would us boring out the cylinder's to .045" have any thing to do with the engine idling better at the higher fuel pressure?

I never dealt with a Mitsu V6 before so I don't know if they are peppy at low end or kinda doggish. I do know they are expensive to work on. I like this Monty, it seams well built and solid. Any advise would be greatly appreciated. <img src="/forums/images/graemlins/cheers.gif" alt="" />