Edelbrock E-Street vs Performer RPM Heads

I just got a set of E street, you do not need the RPM heads at the higher cost unless you are running a roller cam. Even that part is a bit confusing as they both say good to .600 lift. Mine are for the 440 I am building for my Duster. (5090 heads)

My cousin has a home based head porting shop, and he did some light work on my heads and the difference is crazy. He has not even corrected the valve job yet and they are already flowing over 300 without having to make the intake runner too big and hurt the low end. I will post another one once he corrects the factory valve job.

Sorry, I don't know why it attached twice

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