Is a Serpentine Conversion Worth the Money?
Nearly every modern car uses a serpentine drive system so they must be better...Right?
Absolutely! Why? Because the belt tensioner keeps constant tension on the belt at all times. This compensates for belt stretching, flexing of the brackets, pulley wear and a whole lot of other evils that can result in a thrown belt and being stranded on the side of the road. Another advantage is that serpentine systems are cheaper to produce. There is only one belt and the brackets don't need to be adjustable. Modern cars have A/C, alternator, water pump, smog pump and power steering - that would mean at least 3 belts with a traditional V-belt system and a whole lot of adjustable brackets.
So a serpentine conversion is a good idea...Right?
Not Necessarily.... That's because most serpentine conversion kits do not have a tensioner pulley. A lot of aftermarket conversion kits re-use the old standard rotation water pump and keep tension on the belt with a manual adjustment or turnbuckle. This defeats the whole purpose of the serpentine system! In fact, it is worse than a V-belt system. That's because V-belts requires less tension to work properly. By design, the V shape helps to wedge the belt into the pulley and gives it a firm grip without a lot of tension. On serpentine belts, the ribs provide guidance and tracking but there is no wedging action. Don't take our word for it though...the Machinery Handbook, 27th edition states "V-ribbed (serpentine) belts do not have the wedging action of a V-belt and thus operate at higher tensions."
To make maters worse, most serpentine conversion kits eliminate the sturdy steel brackets and replace them with thinner aluminum brackets. This is fine for a v-belt system, but a serpentine conversion requires more tension. When you accelerate quickly (like most gearheads do), the extra stress causes the brackets to flex. Since serpentine belts are more sensitive to tension than a v-belt, you get belt slippage, squealing and premature wear.
To be fair, there are some high end (and high priced) serpentine conversions out there that include a tensioner pulley. If you can afford one, then you should go for it. For the rest of us, I recommend staying with the traditional V-belt set up.