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Old 01-10-2008, 05:30 PM
300Deluxe 300Deluxe is offline
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Guys I certainly appreciate your input.

I've read horror stories on various forums of cams failing prematurely. This is why I'm trying to go about this build as meticulous as I can. I've read about cam break-in procedures at-length and hope to follow the guidelines provided here and elsewhere.

There seems to be differing opinions on the valvespring issue here. Here are the specs of the springs provided with the heads:

1.47 Dia

Intalled Height (Intake): 1.88 (Exhaust): 1.88

Seat Pressure: 130

Open Pressure: 320

There are various check boxes with the different types of cams on the spring card with "Hyd Roller" checked.

Lunati's recommended valvespring specs:

1.266 Dia - single spring

Installed Height: 1.75

Installed Pressure: 108

Open Height: 1.25

Open Pressure: 339

Coil bind height: 1.060

Spring rate: 462 lbs/in

I realize we need to compare apples to apples here, but the above info is what I found on both springs.

Judging by the numbers, the provided springs are obviously heavier. So F-bird, do you think that these will be OK for my cam? My line of thinking is the fear of having too much pressure on the lobes. You suggested removing the inner springs. What are the specs of just the outers? Are they similar to Lunati's recommended specs?

454C10, you recomment NOT removing the inner spring, right? What would your alternative be?

I apologize for the redundancy. I just want to be confident before I start assembling anything.

You all have already been a big help.

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