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There is no difference between HO or base model rockers, it was the valve geometry that made the ratio difference.

I'd say check your regulator to see if it's supplying the proper amount of fuel, and changes properly to suit the engine. Also, how are you timing the distro? Did you disconnect the ECU controller shunt (gray or black connector near the TFI) before timing? If not, then that's your issue.
 

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Well, to time the engine the ECU can't control the TFI module. That little shunt piece is for the ECU controlling the timing. Pull that out, and you're at base timing, which should be 10.

As for the low end grunt missing, check your valve timing, I'm betting you're about 3-4 degrees retarded.
 

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I doubt it's that as the lifters between GT and base models are the same. I'm at work and don't have the hard numbers with me (manuals are at home). It wasn't just the length, but the angle the valves are installed...not quite the same as the CFI heads.
 

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The HO valve might have a problem with the shrouded CFI comb. chamber. I'm thinking the HO valves may be more horizontal than the CFI valves, to improve airflow, which would result in a little change in rocker ratio, too.
 

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Correction....look at the roller rocker thread. 1Low posted up some pics of them mounted on his HO head when he got them. If you look closely you'll notice the same notched spots on all his rocker bosses.


Also, your fuel pressure is fine. The pump operates at a higher pressure (or can operate) but the regulator takes the pressure down to 39 for the injectors. The CFI pump runs about 45 psi, which is taken down to 14.7 at the injector...big injector, low pressure.
 

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Is there any wear on the rocker, though? I'm guessing the anodizing would wear off it if the head wore that badly....or else they weren't torqued properly? I'm just going at this as logically as possible. Oh, maybe some measurements of the damage (diameter and depth of the crater) would help.
 
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