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Old 02-14-2025, 02:41 PM
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zippy zippy is offline
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470cid .040" overbore, 4.25 stroke, #64 heads 9.6:1 comp. 041 cam, (Melling SPC-8) set at 109 ICL, Crower cam saver lifters, Comp 995 springs, 1.65 Scorpion roller rockers. TH400 3400 'tight' converter, 3.08 rears. She lights the 275/35-18 Nitto 555 with ease!

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  #2  
Old 02-15-2025, 04:23 PM
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NeighborsComplaint NeighborsComplaint is offline
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068 is pretty tame in a 455. If you want a little "edge" to the sound of the car and still retain drivability, the Pontiac 744 and Summit 2802 are hard to beat. The Summit gives more lift with 1.5 rockers than the 744 and will be easier on the valve springs. The lobe profile of 744 is going to make it sound edgier but you'll have to go to 1.65 rockers as it will have only .406" with 1.5 rockers. I have no idea how it would perform w. only .406" lift but I am guessing it will sound stronger at idle than it actually runs.

Go with RA4 valvetrain including longer valves (2.11" intake & 1.77" exhaust), springs (1.8" installed height) and pushrods with either cam to retain geometry. If you want to take advantage of the 744 cam's capability, you will need 1.65 rockers and clearance the pushrod slots in the heads for them.

I think the Summit 2802 w. 1.5 rockers is the better choice.

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Last edited by NeighborsComplaint; 02-15-2025 at 04:51 PM.
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