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#1
05-15-2025, 11:01 AM
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Contemplating a cam change
I'm in the process of replacing the timing chain assembly in my 71 GTO. Right now I'm running a Lunati BMII cam, .490 lift with 290 ° (advertised) duration. I've been running this cam for over 20 years.
The engine is a stock bottom end 400, with 670 heads. The heads have Ferrea stainless valves, 1.75 installed height with Isky springs. When new the springs had 130 lbs closed and 320 open. Unsorted and only .008 taken off just to true them up. The heads were done in 1998 by a former NASCAR engine builder. I'm also running 1.52 ratio Comp. Magnum roller tip rockers with poly locks. I'm thinking about going to a 744 cam. With the 4 speed I won't have to worry about a converter. I already have an Ultradyne 280-288 that I was planning on using in a future build. All opinions appreciated. Thanks.
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1971 GTO,72 400, stock bottom end, 670 heads, Lunati BMII cam, headers, iron intake Q-jet, four speed. Best 60 ft 1.806in 2004. Best 1/8th mile e.t. 8.46 with 3.55 open rear 85 Grand Prix, 70 400, casting 62 heads stock rebuild, Turbo 350 trans 78 800 cfm Q-jet modified as per Cliff Ruggles book. 87 F350 6.9 4 speed dually A poor man has poor ways. |
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