Actually the turbo is on the bench for a rebuild, but even without the forced induction, all the other engine mods I did add up to a significant amount of additional horsepower, making for quite a good running engine, and still a 70mph cruiser on the highway.

Really? What kind of mods? The engine in my mine just blew a couple of weeks ago. So i due for a swap. Wouldn't mind putting some more ponies in to it. Not a great deal though. Just a bit more jam for the highway and through the mucky stuff. Just don't want to be breakin driveline parts either.

Well, I can tell you this much: If your gonna swap engines, find a 16v first. If you can afford to throw a few bucks at it, swap out the injectors for Nissan Pathfinder v6 200cc ones, advance timing 2 degrees,  go with a header, Calmini or Thorley, 2" exhaust, gut or eliminate the cat if you can get away with it, Magna Flow muffler, and  K+N air filter. Chuck the clutch fan in favor of an electric one, I think mine's a 14". A good set of plugs, wires, cap and rotor and a good valve adjustment will add up to a nice noticable power boost.

what year pathfinder injectors?? i have my timing set at about 3*...factory is 5*, this was a bit better for mine....i have a short ram intake and 2" exhaust, if i advance any more i hear spark knock under a load...like going up hills...

90's v6. I'll try and find the part #.  You shouldn't have any spark knock, or detonation with a stock motor that's in good shape. Have you done anything else to the motor?

nope....just rebuilt it about 6 months ago.....and this was the conclusion that i came to....the motor is in excellent shape, i re-ringed and put new bearings in it...i have no idea why it detonates...but it does if i advance more than 3*.....ever heard of that???

I'm wondering if when you put everything back together you got the cam belt a tooth off, or the distributor a tooth off? It would still run ok as you would have enough room in the dizzy adjustment to bring it back into time, but it'll still be off a bit.

Thats what I would check too. Something could be off by a tooth.

Just a thought geeeooo, do you have any overheating issues ? That would also be a symptom of retarded timing.