Freshen up Absolute Speed 5.3 heads or go to Dart?
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It's time to pull the heads and either replace or freshen them up. I have AS 5.3 heads with 2.04 intake and 1.57 exhaust valves. They have Comp 977 springs as well. I have the Texas Speed 231/237 cam in the car.
Over the winter I plan to pull the heads, get rid of the Comp R lifters (need a good suggestion on this as well) and either sell the heads and go to Dart 225 heads or see what I can do with the AS heads. I plan to keep the 231/237 cam for now.
On the Dart heads, will the 2.05/1.60 valves clear the pistons? (stock shortblock) I have a very good local porter that can flow and tweak them as well. What spring and lifter would work well?
On the AS heads, is it worth reworking them or just dump 'em?
Next winter is a forged 347 with a matching cam.
Over the winter I plan to pull the heads, get rid of the Comp R lifters (need a good suggestion on this as well) and either sell the heads and go to Dart 225 heads or see what I can do with the AS heads. I plan to keep the 231/237 cam for now.
On the Dart heads, will the 2.05/1.60 valves clear the pistons? (stock shortblock) I have a very good local porter that can flow and tweak them as well. What spring and lifter would work well?
On the AS heads, is it worth reworking them or just dump 'em?
Next winter is a forged 347 with a matching cam.
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I'm kinda in the same situation as you. FMS is building me a 408 as we speak, and although I'd like to get Dart/ET heads right now, the fact that my clutch and transmission need rebuilding are preventing me from being able to afford it. Allan already did some extra work on my Absolute Speed heads, and it did pay off, as I picked up 20cfm all the way across the board on the exhaust side. I am also making pretty good power considering I'm only running the F11. I guess I'll see how these work out on the 408, and get some new heads around income tax time. Allan is gonna open up the chambers a bit, I may see if he can work the intake side any further.