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Old 02-09-2013, 03:43 PM
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if what you really want is a more torqey engine overall. replace the 350-290 cam.
Its a bad choice in a low compression engine .. Keep the cam choice mild.

but you can combine a mild cam with headers, head porting and a better intake etc, to good effect.
87 octane will only allow so much practical compression ratio.
The thickness of the new gasket is the primary concern. thicker than the original will lower the compression ratio.

Keep the real measured cr less than 9.20:1 for 87 octane. the mild compression ratio limit dictates a mild/moderate cam.
pretty much any all mild moderate cams will be an improvement over the 290hp cam.
The 290hp cam is not a bad cam, its just a bad cam in a low compression ratio engine. (unless you got a blower or a turbo)
But advanceing this cam by about 7-8deg helps, as the intake valve closes sooner.
Degree it first. then adjust its installed position. "cam phasing"

if you want to juggle the engine compression ratio yet stay using 87 octane gas then being accurate matters.
So first you must measure the real compression ratio of your assembled engine using all the critical factors.
The adv cr is 8.5:1. the real cr is probabily lower than that.
Measure what you got , first. Now you will know how much to change the chamber volume.
keep it 9.20:1 or less for 87 octane.

If you are willing to run 92 octane gas you can run a 10:1cr.

Last edited by F-BIRD'88; 02-09-2013 at 03:58 PM.
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