What's the most basic and affordable way to improve performance in my 1986 Mustang GT 5-speed?
Start with a fuel system cleaner, new plugs, wires and a new air filter. That should get it back to the stock HP. Headers would probably be the next step for any meaningful horse power gain. A cold air intake and low flow muffler will gain a small amount but usually not worth the expense.
1st-Install a BBK Cold air intake system-$199.00,then install a flowmaster cat-back exhaust-$499.00,other mods,install rear gears 3:55 or 3:73 ratio-parts-$159.95,labor-$250.00,those 3 add-ons would give you noticable power,than better mods would be cylinder heads(trick flow),intake manifold(trick flow),headers,then you are getting much more power,I installed a 347 ci,in mine
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