I have a 1970 Camaro, I put a 396 in it last Spring and I'm running a TH350 tranny and everything is going good. Well this past week I installed 3.73 gears.....it runs awesome! But, my speedo is way off and it shifts too quickly IMO. With the flow of traffic at about 45mph, I'm in 3rd gear at 2200 rpms.....is this normal? What do I need to do to fix the speedo problem?