Your 89 injectors flow enough fuel to break things as they are with just pump ajustments. And, unless you go wtih the smoky PODs, you wont see much power increase with the 190s or other similar injectors. It IS a good idea to get the injectors checked for pop pressure and atomization, though.
First thing is to get some gauges, and put the pyrometer probe in the manifold, and get a 40psi or higher boost gauge. My nonIC 91 had only 125mm of fuelling, and it'd peg the boost gauge in 3-5 gears. Next, is the air fitler of your choice- I've had good luck with stock and BHAFs; K&Ns are kinda marginal, depending on the dust particulate size in your area. I have no experience with the aFe ProGuard& filters, but they are supposed to be better than a K&N.
Next is exhaust and pump tuning. There USED to be some stickies regarding VE performance, but they have been taken down, apparently. Very good reading. Look for "VE Performance" in the search option.
Change all your fluids and put good stuff in there. Oil is cheap- just ask my mother- she is on her 3rd set of LSD clutches ($90 a set) because she wont go for synthetic oil in the rear end. ALso change all your filters while yer at it. Is it an auto or stick? If it is the Getrag 5speed, there are some tips on dirving styles that will enhance the longevity of it- namely dont lug it, and keep the oil level about 1-1. 5qts above stock. If it leaks, re-route your vent- install a hose up into the engine bay.
Good luck and welcome aboard.
Daniel
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