Budget 318 build

I just installed that same cam in a 75 dart with auto/and a 276 gear I was surprised how well it ran and with no notice of power lost at the bottom end I think the smaller ports on the 318 help keep the air speed up ,the compression only dropped 10 psi but the timing chain was almost falling off the old camshaft could have changed the psi more with a new chain maybe a little also installed a performer intake with a 650 edy avs style carb.