347 or 408

[jonnyk]

Originally posted by soon2Bturbo
You must know a few facts first. 347's are not good for street driven stangs. The rod ratio is too big and will cause early ring wear (blow-by) and may even cause the cylinder bore to become elongated. Basically, there is too much side load on the piston and cyl wall since the piston travels too far down into the bore.

I suggest you don't contribute false information if you don't know what you are talking about. 347's are fine on the street...modern kits don't have any problems at all. Yes, there is more side loading on the pistons, but that isn't a very big deal in sub-6500 rpm applications anyway. You can also run tighter wall clearances with some of the new pistons out there and the thing will last a long time. The rod ratio isn't too big...nor is it too small. It's fine for street use.