Actually the Edelbrock carbs are known as the most forgiving or out of the box carb you can buy. If you cant tune an Ede properly forget about getting a Holley dialed in. Not saying Holleys are bad carbs,they are great carbs,just have to know what your doing when setting them up.
Heavier spring opens the rods later in the power mode.When engine is under a load vacuum drops.When vacuum drops a lighter spring will open the rods easier than a heavier spring.
Like I said you are tunning in the dark. Look up the manual on the Edelbrock site,and get a better understanding on how it works. If you dont know what your doing,you cant blame it on the carb !
Start with the factory ORANGE Spring & metering rod.
