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 eng. compression question ?
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bober
Sitting Bull

142 Posts

Posted - 02 Sep 2017 :  10:37:43 PM  Show Profile  Reply with Quote
A 455 w/6x4's comes in at 180 lbs in a compression test at cranking speed and all plugs removed , Is it poss to get a close est of cr? I was assuming it was at approximately 9.3 -1 . Thanks

cortcomp
Coyote

USA
5338 Posts

Posted - 02 Sep 2017 :  11:03:04 PM  Show Profile  Visit cortcomp's Homepage  Reply with Quote
That sounds about right, but it's the most inaccurate way to guess out there. The cam has a lot to do with it. But 180 sounds very pump gas friendly.
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bober
Sitting Bull

142 Posts

Posted - 02 Sep 2017 :  11:30:22 PM  Show Profile  Reply with Quote
Yes, I put it together with a small cam . I figured I wasn't racing with it so it would be ok . I plan a head change to a set of 6x4's that has been ported and all new springs and Ferrea valves with the 1.77 exhaust and Hs/1.65 rockers and the p/rod holes have been elongated,along w'RA manifolds w/2 1/2 mandrel pipe . I'm hoping this will at least give it a bit more power . I'm sure I'll have to replace the P/rods .
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