741 cam
03-22-2025 | 12:00 PM
#1
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From: babylon,NY 11702-4116
741 cam
Putting one in a 539 4.125 stroke 4.560 bore cmi cool collar ex single 4 850carb does this cam like advance? Low compression 9 2 1 merc aluminum heads single engine 30 ft boat w pad what is best lifter?
03-22-2025 | 02:26 PM
#2
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From: Finland
Have heard only good things about johnsson lifters, so i went with johnsson 2126bbr with axle oling. The engine pulled clean to 6000rpm with heavy valvetrain. My cam is very similar compared to crane 741. Ron sporll 240/245 @050" ,114lsa 108icl.
03-22-2025 | 06:44 PM
#3
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From: On A Dirt Floor
other words, the 741 cam has a 112 lsa so get a timing wheel set up and install it so the icl is 107 and ecl is 117.
03-24-2025 | 11:06 AM
#5
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From: SW Ohio
For your 539ci engine with low compression (9.2:1), CMI Cool Collar exhaust, and a single 850 carb, advancing the cam (4-6 degrees) will improve low-end torque and response, which is beneficial for boat performance. For lifters, solid roller lifters are ideal for durability and performance, especially in marine engines, as they handle high RPM and stress better than hydraulic lifters.
Pretty sure this is a bot.
Thanks. Brad.
