header question
 

hey guys, im looking to buy headers for my 406 sbc. My question is, are there major differences in power gains from a 1 3/4" primary with a 3" collector to a 1 7/8" primary with a 3.5" collector. I can purchase 1 3/4" hookers from a buddy of mine for 265.00 shipped and ive seen the 1 7/8" hookers for 475.00 obo not including shipping, both in great shape with no rust. Should i purchase the 1 3/4"? or does it really make that much of a difference that its worth spending 250.00 more on the 1 7/8"?

jim