I got a 89 350TPI setup in my 87 Monte Carlo SS. It has the serpentine system & stock 105 amp cs130 alternator. I want to get a higher output alternator, specifically the 160 amp unit sold by Hawks ThirdGen Parts. My problem is that Hawks ThirdGen web site says the 160 amp alternator is for 90 - 92 TPI. Why would a 90 - 92 alternator be different than 88 - 89? They are both CS130.