72 upgrade

This is a combo that worked for me. Back in 2000,starting with a 67 Dart, I spent $800 on a Clifford intake,Headers and a Holley 390 along with electronic ignition.The Clifford shorty headers were plumbed into a 2 1/2'' Y pipe and 2 1/2'' single exhaust thru a Flowmaster muffler and completed with a 2 1/2'' tailpipe to the rear bumper.The rear axle was 2.93 ratio.No internal mods were done.In stock form the car ran out of steam at about 90 mph. After the bolt ons the car would top out at 115 mph @ 44-4600 rpm. The stock valve springs were done at that rpm. I then went with 340 valve springs installing them with the head on the block and moved up to a Edelbrock 500 carb.This gave me 52-5500 rpm and would peg the speedo at 120 mph.Fun daily driver.I drove this car on several Hot Rod Power Tours and suprised many when they found out it was a lowly 225 slant six.As stated in the begining this is what worked for me,your results may vary.