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Old 02-05-2013, 09:46 PM
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That crane cam need a much different timing curve to idle and drive nice with a auto transmission.
You need 26deg base at idle ....a short limited travel 10deg advance curve 36 deg at max advance.

Then using ported vacuum, a 12-15deg vac advance curve. aprox 8-10deg at hi way cruise speeds.

Until you modify the mechanical curve and shorten it to allow increased stable idle timing that does not drop
below 26deg at idle it will idle like crap and stall.
You get this by limiting the mech advance curve to 10deg.
Now you can reset the carb. Use 4" rated primary power step up springs in the carb. 5psi fuel pressure

That crane cam needs a 10" high stall converter. The generous valve overlap needs a ton of timing at idle.

Depending heavily on vac advance for added advance at idle works on a manual transmission car but not a automatic car
that has to idle "in gear", under load.
vacuum drops when you idle in gear, makeing the idle timing drop and the engine stall, hunt or load up.

More base timing and a shorter advance curve is the cure. needs a high stall converter
Some people simply lock out the mechanical advacne and run locked timing 36deg BTDC
The cammed engine will love 36deg at idle.
( vacuum advance can still be used for part throttle cruise)
Locked timing + vacuum advance works very well on radical cammed auto trans cars.
Use ported vacuum.

Crane cams cam card

Last edited by F-BIRD'88; 02-05-2013 at 10:04 PM.
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