So here's the facts, 67 mercury 390 block bored 30 over 68 427 heads port matched to gasket (intake and exhaust) Edelbrock performer intake manifold port matched to gasket Holly 750 cfm carb Comp cams 280h cam kit Sanderson headers C6 trans (stage 2 internals) Stock converter 3.55 gearing in rear end So tell me what u think this is capable of. This goes in my 62 galaxies 500 4 dr...I am building it now
A few more questions: Most likely the heads are 427 MR and 2.09 intake valves? Which pistons flat tops or dished to go along with the C/R question previously asked. Edelbrock Performer 390 or Performer RPM? The 2nd will get you probably 20 HP over 5000 RPM based on Jay Browns book I'd guess probably 385-400 HP but your combo needs torque in the 3000-5500 RPM range to get the mass moving. That's also what I'd guess for Dyno HP and not "rated HP" as in the marketing game.
See I'm not sure because I dont know how to calculate it with the 427 heads The 390 had 9.5:1 But I don't know how switching to the 427 head affects that#
So the heads are off the 427 2v. With the 2.022 valves I only have the performer intake right now but one I get more cash I will get the Rpm. Also they are going to be butterfly cut pistons for valve clearance
Jester, do some research and find out the head cc's, piston +/- cc's, head gasket compressed thickness, deck height, piston height, and figure out what you got before you put it all together. My first motor was a real bastard low compression POS. Since then I learnd to do the math and figure things out to get things in line for a good high performance motor. Look at other builds that will help you out immensely.
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