calculating what amp i need

I have a 1980 Fiat spider convertible. While the top was down I always had a a problem hearing the speakers since they were placed on the corners near my feet so i made a custom box and installed Alpine type R components in the box and the tweeters a bit higher, Initially i had a Boss 800Watt amp from a friend but that eneded up burning out so now I need to get another amp and wanted to know that size amp to get. The deck is a Sony CDX-S2000-Specs. http://www......com/item_1929_Sony-CDX-S2000.html Speakers Alpine Type-R SPR-17LP-Specs. http://www.crutchfield.com/S-ZC4Gq8qOnvq/p_500SPR17LP/Alpine-Type-R-SPR-17LP.html Car had a 65Amp alternator Is there some type of calculation?

Here's the method I use.  First, calculate how much money you can spend.  Decide how many output channels you require (if it's for subs, usually that means mono.)  Decide how low a load it must handle (how are you wiring the subs?)  Then, ignore all the low-end brands (like Boss. Crunch, etc) and purchase the best amp you can possibly afford from a good quality manufacturer (like Alpine, JBL, JL Audio, etc.) ignoring things like power rating.  Install it properly.  Rock and roll.Support the12volt.com

In terms of load how would I find that? This is for component speakers no subs. Saids RMS range is 2-50watts RMS max is 250

What's the impedance of each set?  4-ohms?  2-ohms?  That's the load it places on the amp.Support the12volt.com

4 ohms Sensitivity: 87 dB at 1 watt Frequency Response: 35 - 30k Hz RMS Power Range (Watts):2-50 Peak Power Handling (Watts):250 Impedance (Ohms):4

50 watts per channel @ 4-ohms.Support the12volt.com

you figured that by the range??

You said the speakers are 4-ohms and are rated at 50 watts RMS.  That's all you need to know.Support the12volt.com