That's the amazing thing about the motor mount inserts, they're about $30 for a set to do both the upper and lower mounts. There is just a slight interior vibration, really not that noticeable after you sit in it a couple times. The noise just makes the exhaust a touch louder. Performance-wise, it pulls harder and stronger, takes away the hesitation. I'm honestly not sure if a dyno would show you a difference, but you can definitely feel a difference. More power to the ground is what they basically accomplish. For 30 bucks it's well worth it. The install isn't too bad, you just need an extra set of hands to get the mount out and get the inserts in.
Edelbrock makes a 4-2-1 header.. and I have heard both positive and negative about hedmann, mostly positive though. Summit racing has the Edelbrock header for $270 and the Hedmann for $240.
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