That's a realistic approach to power. For handling, sways are #1, springs are a plus. There are a lot of drawbacks to lowering springs such as harshness, clearance, etc. A good alternative is a set of R Sport front springs found on the '79 GT. Not easy to find but they do pop up on ebay. Slight increase in spring rate but no change in height. Check bushings but don't replace unless failed. Bushings are available in poly now but harshness may be an issue. A set of good braces are a big plus after everything else is done. It surprised me how much they improved the feel. Firewall to strut tower are not too expensive. Strut to strut gives the best improvement. IMHO you want a very strong brace in this case. Any flex in the brace negates any benefit. I have a Bucina in one car and an old SAM Stefansson in another. Similar design. Shocks are subjective. I love Bilstein but others are very good too. KYB tends to be harsher. Good wheels and tires are important. Other small things can help. A GT or Turbo steering wheel has a smaller diameter and feels quicker. A R Sport wheel is great but same size as a turbo wheel and very pricey (when you can find one). If you have a manual tranny, a quick shift mod is cheap and improves feel. Basically, have 3/4" welded into lever below the pivot ball. It shortens up the shift pattern. Not applicable for auto, of course.

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'93 850GLT
'83 242TI Flathood