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Old 09-20-2017, 09:55 PM
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Location: Louisa, Va
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Charlie, I pulled the motor down and the rod bearings showed too much timing. The valve relief scallops on the edges of the pistons, where it gets paper thin, was cracked and broken. I ground out the thin areas and polished to a smooth finish. I had 10 degrees pulled but will go to 16 and work it from there.


70 bird, I have a chassis dyno with a wide band showing 12.7/ 12.6 A/F. I will richen it up a bit. Strange thing is that on a 300 pill it only picks up 141 HP. Motor puts down 612 and on spray it put down 753. It is blowing through the converter though. I called PTC and they sent me a nitrous converter. So I am making changes.

Steve

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67 Firebird 3440 lbs, Pump gas 537 IA2, tiger heads, 4.86 rear, 32 x 17.5's, full interior, 4 mufflers, street shape 1.36 60', 6.11@113.42 1/8 mi. 5.67@123 on small shot.