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Taking baseline engine readings - prepping for topend refresh

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Old 01-19-2013, 03:24 PM
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TedH
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Default Taking baseline engine readings - prepping for topend refresh

@ Idle:
65-70psi (hi volume)
800rpm
36 degrees timing

Is my timing too far advanced at idle? That is with the distributor vacuum line connected or plugged (no difference).

Current equipment:
Rebuilt OEM ram air with K&N filter
Q-Jet by Lars (I need to confirm the metering rods and jet sizes... hope I don't have to adjust too much)
Edelbrock Perform 3701 intake
Accell Performance HEI with performance recurve
Crane Energizer 272H10 cam and lifters (I have a spare in-box, NEW ever used 272H10 cam and lifters that I will sell soon)
Cloyes True Roller Timing Set
Summit stamped long-slot rocker arms with anti-gal pivot *****
Federal Mogul H345NP pistons (bored .020 over)
Darn Iron Eagle 180cc intake, 72cc chamber 2.02/1.60 valves, single 1.250 springs
Mellings high volume oil pump
Hedmann 1 5/8" long-tube headers, Jet-Hot coated
True duals with h-pipe
Dynomax Super Turbos
Bow-Tie stage 2 700R4
Dana 44 with 3.54 spicer gears

Last edited by TedH; 01-19-2013 at 04:04 PM.
Old 01-19-2013, 05:05 PM
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gcusmano74
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Sounds like a lot of initial timing. All the following specs are in engine degrees.
You want to set the initial timing to about 14 degrees, and have the mechanical advance begin at 1000 or 1200 RPM. Should be all in (36 degrees total; 14 initial and 22 mechanical) by 3000 RPM. Add 14 or 15 degrees of vacuum advance. Make sure your canister is giving you all the advance at the vacuum levels seen at idle and cruise. If you have a real lumpy cam, you will need a canister that gives you max advance at much lower vacuum signals than an L48 cam.



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