Quote:
Originally Posted by 61-63
The above is what I will have is this acceptable? The springs are Comp 914-16 and the cam is a Comp special order hydraulic roller 112lsa with .230/.236 duration and .641/.645 valve lift using 1.65 rockers. I have the cam and lifters and the heads are done so I'm hoping I don't have to buy anything else. This is a street car not a race car.
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THIS IS A KEY SENTENCE: "This is a street car not a race car."
You also have a fairly mild camshaft but with decent valve lift.
Quote:
Originally Posted by 61-63
Installed height is 1.800 and seat pressure is 165 lbs. Valve lift with the 1.65 rockers is .641 and .645 which results in compressed heights of 1.159 and 1.155. Coil bind is 1.100. Spring rate is
367 thus open pressure is right at 400 lbs. both valves. As I said the heads are done. Jim Robertson did them and they have T&D shaft rockers in them. I have checked this board and others on the net re coil bind clearance and as usual answers from the worlds experts are all over the place. Hence my asking here. I'm hoping some people like Tom S., Cliff Ruggles, and Tom Vaught, and a few others, will see this and respond to it. I would call Jim Robertson but hate to bother him. Jim Robertson built the heads for a cam with only .026 and .023 less valve lift than the cam I am going to use now so I would think I'm OK, but I'm a carb guy not an engine guy so appreciate hearing from those who know these things.
Exhaust is .055.
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A few good points: You have T&D shaft rockers and Mr Robertson did them.
a) I am not sure how much deflection, if any, those rocker arms have.
So we assume that they are true 1.65 rockers and the cam lobes were ground correctly. A soft checking spring would give you the max valve travel
towards the piston. That check would allow you to determine valve guide to retainer clearance. Something to check but we are talking actual springs installed on the heads and the spring reserve before solid coil bind.
Coil springs today are designed with "Surge Dampening" built into them.
Some coils will actually touch occasionally. Spring surge kills valve springs.
All that being said, have you actually assembled everything on the engine and now are checking things like Retainer to Valve Seal clearance, Valve Spring Clearance before solid coil bind, actual Rocker Arm Ratio for the rockers and found the rocker arm with the greatest valve lift for that shaft specific head assembly?
How much of this checking was done by Mr Robertson?
Tom V.