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I would install it with the stock timing to begin with and try driving it. See how it responds. Once you get the hang of taking the timing cover off it is easy to change out a timing sprocket. Loosen bolts for water pump pulley and crank pulley first to avoid hassle later. Remove belts, water pump pulley, crank pulley, then remove all bolts from the timing cover (lots of them, some almost hidden). We changed the timing belt on my son's Metro with 3 Tech sprocket in 2 hours in the driveway in the dark a week ago and did oil change as well).
Tip: I marked the 3 Tech sprocket with a sharp punch to identify the timing alignment mark after installing it. It most certainly came in handy the other night. The 3 Tech sprocket is a new stock unit turned 180 degrees and a new hole is drilled. It may lead to later confusion if you don't mark it EXACTLY (scribe or punch a new alignment mark) in the metal as the sticker fell off that marked the new timing mark. The 3 tech sprocket gives you the ability to bolt it up 180 degrees and get stock settings, too. You can install it either way, 8 degrees or 0 degrees.
Consider this a nice time to put in a new timing belt. They fail by losing teeth...like my son's did after 145K miles. Don't forget to loosen the 2 nuts on the timing belt tensioner and use the spring to reset the tension. The FRONT length of timing belt should have zero slack as the engine and cam turn in the same direction as the tires going forward.
Temporarily slap the plastic timing cover on and the crank pulley again to make sure you still have zero degrees, Top Dead Center, before blessing the whole thing. You should turn the crank backwards (CCW) and bring it back to zero to make absolutely sure the forward side of the timing belt is in tension.
OK, on my Delta cam, I made my own 8 degree pulley by filing the side of the cam sprocket alignment pin hole with a needle file. It doesn't take much (likje maybe .006 inches). Then I put a spot of braze on the opposite side of the hole to take up the backlash and gently filed it to make a snug fit. I would have bought the 3 Tech but found myself changing the cam one sunny morning without pre planning. That's why I made my own.
Somewhere on this board I read that a timing sprocket tooth width is 18 degrees. I drilled a hole in a sharp ended piece of scrap aluminum and double nutted it to the valve cover hold down stud. It served as a pointer very close to the sprocket tooth so I could do my handiwork. I also turned the cam and sprocket backwards 1/6 turn from the alignment mark to find that natural low spot where all the valve springs send the cam on ts own. At this point I aligned the pointer and filed the timing locater hole and guestimated where 8 degrees was.
Don't forget the top alignment mark is now 8 degrees off and the cam sprocket needs to be turned slightly to make the belt fit. That's where you mark the new timing alignment mark as mentioned above. Saves confusion later.
If you get in a bind or want to talk it thru first, send me a private email and we'll get 'er done. ...Kim
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