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76 258 CJ-7 Camshaft specifications

Does anybody have the original camshaft specifications for the '76 CJ-7 258

6 cylinder engine? If I need to replace mine, what are good grinds to consider? Crane makes one for a 1000 RPM starting point that's made for fuel economy and another that produces a smooth idle but better performance in a little higher RPM range. What are your preferences? o_o_o_o Best Regards, /| ,[_____], Jim, WP3JQ |¯¯¯L --O|||||||O- ()_)¯()_) ¯¯¯¯¯ )_) EM60qk 30.447439N 086.628959W
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Drink
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The Cam Lobe Lift is 0.253, and the duration is 262° for both the Intake and the Exhaust, with 34° overlap. Intake opens 9° BTDC, and closes 25° ATDC, Exhaust opens 57° BTDC and closes 25° ATDC.

Reply to
CRWLR

Reply to
L.W.(ßill)

Absolutely! If you are planning on idling over obsitcles, you will want an entirely different cam than if you intend to blaze a new groove down the interstate.

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CRWLR

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Drink

Reply to
L.W.(ßill)

Reply to
Drink

No 10:1 on pump gas? I run 10.5:1 on 93 octane

Reply to
Timo

Reply to
L.W.(ßill)

I also run over 10:1 in my 350 Chev. This is a true blueprinted 10.6 compression ratio on 92 octane. Everything was CCed. It is not the norm to be able to do this however. My combustion chambers are polished to an almost mirror finish, and all sharp edges are removed from the piston tops. I also have aluminum heads which is usually good for a half a point of compression or so. They are more resistant to pinging because they draw more heat from the combustion chamber. A bigger cam also lets you get away with a little more compression. I also played around a lot with timing. My truck is light (S10) and has 3.70 gears with 26.5" tires and a 3.06 first gear, so there isn't as much load on the engine as there would be in a full size truck. I wouldn't recommend running much over 9:1 for most 4wd applications on pump gas though.

Chris

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c

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