Big Block timing

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Sep 12, 2008 | 01:07 AM

75_yellow

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Instructor

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Big Block timing

What is a good rough guess that i should look at as far as timing on my big block total advance and base settings?

Sep 12, 2008 | 01:53 AM

Peterbuilt

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From: mount holly NC

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Base timing is between 4* to 12*, check out BarryK's Sticky ( at the top) for great info, PG.

Sep 12, 2008 | 02:06 AM

FB007

Burning Brakes

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Idle 16* .36* at 2800 RPM. 52* with vacuum advance engaged at 3000 RPM

Sep 12, 2008 | 06:51 AM

baxsom

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From: Rockledge FL

idle at 16*
is that a good estimate for all big blocks
i know the book for my 72 454 says 8* i believe so i just wanted to make sure.

Sep 12, 2008 | 08:25 AM

capevettes

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From: Cape Cod, Mass.

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Quote:

Originally Posted by baxsom

idle at 16*
is that a good estimate for all big blocks
i know the book for my 72 454 says 8* i believe so i just wanted to make sure.

Whatever it takes to get to 36 at about 2500-3000 RPM's. My big block is set at 12 initial to get 36 total.

Sep 12, 2008 | 09:03 AM

sxr6

Pro

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From: Nice Lake Ontario

Quote:

Originally Posted by baxsom

idle at 16*
is that a good estimate for all big blocks
i know the book for my 72 454 says 8* i believe so i just wanted to make sure.

The only reason manu's set base timing so retarded is because it creats hotter gases flowing thru exhaust to burn unwanted pollutants. The only reason!

As above says, set timing at 36* (38* if cammed) with vacuum unplugged at 27-2800rpm! Depending on vacuum canister that should give you 45-50* with vacuum plugged in. Let idle timing fall where it may, means nothing anyway, as long as it rolls easily on starter.

A rollback timing light is a great device for this kinda stuff, wish I had one of my own

Sep 12, 2008 | 09:26 AM

slapshot 496

Instructor

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From: Coldbrook Nova Scotia

This really is a loaded question! If the motor is stock,,heads and cam mainly.Then the manual is likely a good starting point however if you have a longer duration cam with increased overlap then you will have to increase your initial accordingly!! but as the previous post stated "initial" really isn,t a huge concern ..unless the starter is binding..so fiddle with the initial but keep the total between 34-38.You can also use a vacuum gauge ..look for the highest reading ,if it,s really low increase your initial until it peaks this will get you very close..cheers

Sep 12, 2008 | 11:52 PM

Jeff_Keryk

Drifting

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From: Los Gatos CA

My stock 68 427/390 distributor has 16* centrifugal advance, so the 4* factory setting is pretty close. 4 + (16 times 2) = 36 total. I do use lighter springs to bring it in faster...