[DeTomaso] DAN JONES YOUR INPUT REQUESTED

[clewis at dmn.net]

Dan when are you available for a phone discussion? 

Last year middle of the season a beehive spring broke and dropped the valve. 

I am ready to rebuild but have a number of things I would like your input on. 

The springs were PAC Beehive 1220XX. Good for .650 lift. They had started to experience cascading failures. Broke one and replaced 
it and then a second different one failed and dropped the valve. 

The actual lift is .665, but a phone call with PAC when the engine was built said this should not be a problem. I spoke with them 
myself as did Jeff Lawrence. Clearly either this was wrong or somehow the engine was over revved. 

PAC has provided a full set of replacement springs, the same 1220XX. 

I am thinking if I don't change the cam I need to use 1255xx, good for .700 lift or 1295xx good for .750 lift. 

I suspect the damage to the bottom end is relatively minor. The valve dropped after the engine had stalled and I was trying to 
restart the engine (clutch was disenganged and there was no weight of a moving car against the drivetrain. 

Should I consider titanium intake valves to take weight out and stress out of the valve train? 

Will the reduction in weight enable the valve train to have better control? 

Will titanium valves with the proper coating be durable in a street application? (Isn't this what the new Corvette uses?) 

How would you approach this rebuild to address the obvious and maybe not so obvious issues? 

Best Regards, Chris Lewis