Would it be possible to use a stock n/a 2.6? I've read through the parts list and it sounds like its not all that complicated if you could just stick the turbo parts on the n/a block and go. I've done an OEM FI swap before and have also plumbed an intercooler so it would definately have that. Not looking to make beyond stock HP, just want some decent power for daily driving. Would probably never see peak hp/rpm anyways.

Stock NA does not have the oil squirters that the turbo block has. They can be added (Kevin C did to one of his), but the squirters themselves are hard to find they say.

The CR is also less on the turbo. (Think I got that one right...?)

The NA block does have the boss to bolt the knock sensor to.

Opinions of those more knowledgeable is that the pre 88-89 stock boost at 7PSI would be pushing it.

When I first did my swap I used the bone stock NA 2.6 bottom end. No oil squirters and 8:1 pistons. Ran 7psi and had minor to moderate detonation issues comming on positive pressure, between 0 and 2-3psi, and climbing long hills.

Any clue whether this was CR related, gas, or maybe an electrical/mechanical problem? Is 7psi stock? I may have a lead on the swap parts close to me. Anyone else used a truck engine for this?

I assume you still put the detonation sensor on the block? In which case, the ECU would have adjusted as needed, just more often vs. turbo block?

There is only so much retard available from the knock box and det sensor. If you use a stock CR of 8.7 for a carb block, and 7.0 for the turbo motor, that's an increase of almost 25% in CR.

If you look at it another way (and somewhat simplisticly), at 7psi of boost and it's effect on effective CR, that's about 1.5 x 8.7, or 13.5ish to 1, and you're past the detonstion limit of pump gas, so it takes a hammer to the pistons and ring lands, regardless of the amount of spark retard you throw at it.

Youjust might get away with that CR on a better breathing 4 valve head like a 4G63T motor with a better pent roof combustions chamber, but the 2.6 just won't take it without some addons, like water injection.

Well SOB, so on a truck engine even with highest octane pump gas (91-93), you're screwed?

I've done an N/A to boost swap before, but there wasn't that much difference in CR so it wasn't an issue. <img src="/forums/images/graemlins/frown.gif" alt="" />

I think it's been done, but I wouldn't. Too risky. I think you can probably get by without the oil squirters if you have to, but I'd at least buy a set of os stock starion pistons.

IIRC, I had to shorten the pickup tube on the starion pump when I used it in a d50, but I think the engine positions vs. the front axle are diff between monty and pickup.

Theres for sure a difference between the 2wd and 4x4 D50 pick up tubes, due to were the steering cross arm goes across the pan at for steering. Never dealt with a Montero or Starion yet, keep waiting for the right/cheap one.

I ran 8.7 to 1 CR pistons with a stock Starion turbo system and got that same light part throttle detonation. I found that the primary spring on the advance weights on the Starion distributor was super light allowing a lot of mechanical advance at a low RPM range.

By swapping in the springs from the carb motors distributor I was able to slow the advance curve so that I did not get the part throttle detonation.

Kevin