this was my answer on 4-1 in answering a pm


16 afr is tring to explode your engine maybe get rob needswings adjustable furl system and set it around 75 psi
with the stock fuel and without a extreme tune you can't run the stacked pulleys what was the afr before when you had the higher hp,,, something
is wrong with tune,,,pulleys,, or fuel system,, if u still have cats on the car they could be going bad. jim
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