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For an '86, the 4-speed 200-4R is original equipment. Whether or not it's still there is another story.
Take a look from underneath at the pan and this should help identify which transmission the car has now.
If the engine is not original, I wouldn't waste a dime, or a single minute of my time on converting a regular 305 to a HO 305.
Even the HO 305's are incredibly disappointing.
All that money and effort is better off being put towards a healthy 350 to replace it.
For an '86, the 4-speed 200-4R is original equipment. Whether or not it's still there is another story.
Take a look from underneath at the pan and this should help identify which transmission the car has now.
If the engine is not original, I wouldn't waste a dime, or a single minute of my time on converting a regular 305 to a HO 305.
Even the HO 305's are incredibly disappointing.
All that money and effort is better off being put towards a healthy 350 to replace it.